West, Ian M. 2014. Burton Bradstock - Bridport Sands and Inferior Oolite, Jurassic Coast. Geology of the Wessex Coast website. http://www.southampton.ac.uk/~imw/burton.htm. Version: 31st October 2014

Burton Bradstock, Jurassic Coast, Geological Field Description

Ian West,
Romsey, Hampshire

and Visiting Scientist at: Faculty of Natural and Environmental Sciences,
Southampton University,
Webpage hosted by courtesy of iSolutions, Southampton University
Aerial photographs by courtesy of The Channel Coastal Observatory , National Oceanography Centre, Southampton.
With many field photographs contributed by Alan Holiday

Home and Contents | East Cliff, West Bay, Bridport, Jurassic Coast |West Cliff, West Bay, Jurassic Coast |Chesil Beach, Jurassic Coast |Chesil Beach - storms | Lyme Regis, Westward | Lyme Regis to Charmouth, Jurassic Coast |Eype Mouth, Jurassic Coast
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The cliff top near Burton Freshwater, Burton Bradstock, Dorset, Jurassic Coast, showing the junction of the Bridport Sands and the Inferior Oolite limestones, with Fuller's Earth above, with Helen for scale

Diminishing Chesil Beach and undercut cliffs of Bridport Sands with Inferior Oolite above, at Burton Cliff, Burton Bradstock, Jurassic Coast, Dorset, 3rd March 2008

A view of East Cliff, West Bay with Burton Cliff, Burton Bradstock, Dorset, beyond, 2011

Burton Cliff East near Bridport, Dorset

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INTRODUCTION

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INTRODUCTION:

Safety

Risk from rock falls at Burton Cliff, Burton Bradstock, Dorset, notice and cliff in 2013

Burton Cliff is a place which is prone to occasional rock falls. Sadly, there was a fatal accident due to a rock fall on the 24th July 2012. Two other people were pulled from fallen sand debris before a second fall and thus survived. The beach under Burton Cliff was then closed to the public for a time (see details further below - "Rock Falls"). Accidents are actually rare, but people should not linger beneath the cliffs and should stay out away from them as far as possible. A narrowing beach here, though, is a problem. The risk is generally greater at high tide; low tide enables a view of the cliffs from a lower and safer position. The exposures of Inferior Oolite limestone on the beach at Burton Cliff are the result of a cliff falls, as this stratum is not accessible in situ. Major falls may occur once or twice a year. Much of the cliff is unstable and these cliffs are dangerous in several places. Members of parties should wear safety helmets, although these are of little use with regard to large rock falls. There is some risk of being cut off by the tide or swept into the sea in stormy weather conditions. Care must be taken when walking along the cliff top, which is retreating with cliff falls, and may overhang in places. Visitors and field leaders should make their own assessment of risk at the time and no responsibility is accepted. This webpage is a description of the geology of the coast here and not a programme to be followed or an itinerary for a field trip. The webpage may even provide some information required and make a field trip unnecessary.

See also: The National Trust (Pamphlet) - Cliff Rock Falls: Why do they occur.
This Includes: "A warming climate means that sea levels are rising and so we must expect more frequent rock fall events in the future".

Do not loiter next to the cliff and move out of it as quickly as possible. No-one should not sit for rest, lunch or sketching in a hazard zone. Always assess the state of the cliffs and look for evidence of danger or recent rock falls.

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INTRODUCTION:

Access
Burton Bradstock is a small village. It is an easy place for parking car but not coaches. There is a parking area for coaches at West Bay, Bridport. Access on the eastern side is at Burton Hive. There is a National Trust car park at the end of Beach Road (SY 491889), next to the shore. This car park has toilets and a cafe. There is access on the west side of the cliff section from Burton Freshwater. This involves a short walk by footpath from the village. There is also a cliff-top footpath between Burton Hive and Burton Freshwater (closed in late July and in August 2012 after a fatal accident). However, see note above, and details below regarding a fatal accident at Burton Cliff in July 2012.

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INTRODUCTION:

The Cliff Section

Burton Bradstock cliff section

Burton Cliff is similar to East Cliff at West Bay but in its middle part the Bridport Sands are succeeded by the full thickness (3.7m) of Inferior Oolite and a little of the Fuller's Earth. The Inferior Oolite is not safely accessible in the cliff but large fallen blocks are present on shore and in these almost the full thickness of the unit can be studied. There is access to the beach near to the stream, the River Bride or Bredy, and 155m east of this point a fault downthrowing eastwards cuts the cliff, dropping the Inferior Oolite capping sufficiently to bring in Fuller's Earth in a cliff top outcrop. Beyond the fault are the large fallen blocks of Inferior Oolite and the details of these should be compared to the graphic log given below.

On the shore at Burton Hive, below Burton Villas, where a rough path descends from the road to the beach, a peculiar white limestone occurs ( Davies, 1956 ). It is unlike any other bed in the neighbourhood. It lies in, on or against Bridport Sands, but is close to a fault that throws Frome Clay and Forest Marble down some 60m to a level with the Bridport Sands. It has yielded a nautilus and a species of the ammonite Garantiana. Buckman (1910 and 1922) regarded it as part of the Inferior Oolite, in age between the Red Bed and the Astarte Bed. He believed it to have been deposited on a plane of erosion cutting through the Red Bed onto the Bridport Sands; later erosion removed this White Bed from the area to the north and northwest before the Astarte Bed was laid down, and a third period of erosion removed the higher beds of the Inferior Oolite at this spot before the Fuller's Earth was deposited. Richardson , on the other hand, suggested in 1915 and 1928-1930 that the White Bed was a neptunian dyke, an infiltration of lime-mud from the sea-floor into the Bridport Sands in the vicinity of the fault.

The old cliff at Cliff End is of Forest Marble and Frome Clay, but it is much degraded at its base as it is protected by a stretch of shingle, part of the Chesil Beach. In this cliff, 200m east of the car park the Boueti Bed can be traced in eroded ground between the footpath and the cliff top House, 1993 ). It yields the brachiopods Goniorhynchia boueti, Avonothyris, Digonella with bivalve and other fossils. In the cliffs below the Frome Clay can be examined and it crops out in the low cliffs at Burton Common and Cliff End ( House, 1993).

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BR1 - BRIDPORT SAND FORMATION - STRATIGRAPHY

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BR1 - BRIDPORT SAND FORMATION - STRATIGRAPHY -

Jurassic Palaeogeography

The European shelf seas of the Jurassic in relation to northern hemisphere palaeogeography

Simplified palaeogeography for the Lower Jurassic of Britain

A map is provided above showing the position of the shelf seas of Europe in the Jurassic. Because this is a very generalised and not for a specific time in the period it should not be used as a precise marker of palaeolatitudes. It does indicate the area of extensional tectonics and basin development at the northeastern end of the Atlantic at that time. Not only was the formation of rifted basins responsible for much accumulation of clay, limestone and sandstone sequences of the Jurassic. In addition, the breakup of the old supercontinent Pangaea led to an increase in the number of spreading centres in the oceans (Lemon, 1993). This resulted in a consequent displacement of seawater from the oceans producing a rise in sea-level. Both the rifting and this process caused the transgression of Jurassic marine deposits over Permo-Triassic, desert red-beds.

Also above is a simplified palaeogeographic map showing the generalised distribution of sea and land in the British area during Early Jurassic times. The southern part of the Atlantic Ocean was opening to the southwest, but the North Atlantic was not open at this time. Shallow shelf seas with some locally deeper basins occupied much of the British region. This map is to set the scene in broad terms and the details varied at different times within the Early Jurassic.

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BRIDPORT SAND FORMATION:

Introduction - Stratigraphy

Jurassic Stages and Dates

Lower Jurassic Strata of Dorset

Lower Jurassic Zones

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BRIDPORT SAND FORMATION ("BRIDPORT SANDS"):

The Cliff Exposure

For more on the Bridport Sands see the:
East Cliff, Bridport section of Bridport Sands

A general view of the Bridport Sands, the Upper Reservoir Rock of the Wytch Farm Oilfield, seen here in the cliffs at Burton Bradstock, near Bridport, Dorset, March 2008

The southeastern end of the cliff of Bridport Sands at Burton Bradstock, Dorset, showing close-spaced cemented beds a short distance beneath the Inferior Oolite, 2010

The first part of Burton Cliff at Burton Hive Beach, Burton Bradstock, Dorset, with the cliff area closed off because of a recent fatal rock fall, 3rd August 2012

A warning notice about cracks in Burton Cliff, Burton Bradstock, following the fatal accident caused by a rock fall

Burton Cliff shows Bridport Sands with cyclical carbonate-cemented horizons. The sandstone is blue-grey when unweathered but has a thing weathered surface layer of yellow. Here, fine-grained pyrite is oxidised to limonite or goethite. The sands contain belemnites and trace fossils and occasional moulds of ammonites. Aragonite shells have been dissolved away.

After a long phase of slow weathering the harder, calcite-cemented bands project and show honeycombe weathering. When, however, there is a cliff-fall as has happened here, then a flatter and smoother cliff face is produced. It requires a significant but unknown interval of time for the hard bands to project again.

The Inferior Oolite is present at the top of the cliff. There are many fallen blocks of this on the shore at Burton Cliff. The limestone is much more fossilferous than the sandstone but marine fossils can be found in both. In the far distance are the cliffs east of West Bay . These are also of Bridport Sands and further information on this formation is provided in the Bridport, West Bay website .

Here is the western end of Burton Cliff. Here there is no Inferior Oolite as the cliff top descends. The valley in the middle distance is Burton Freshwater where the River Bride reaches the beach. Beyond the river is a caravan park. East Cliff of West Bay , also of Bridport Sands is in the distance.

The Bridport Sands here dip at a very low angle, and are, in fact, almost horizontal. They are prone to occasional topples, perhaps along joints that are parallel to the cliff. Such falls, however, occur only at rare intervals. These used to be very rare but now they are common with several accumulations of debris at the foot of the cliff. After such a fall the particular part of the cliff does not show the projection of the hard beds. Only after an interval of many years does weathering and erosion by wind and rain wear back the softer material and leave the carbonate-cemented beds protruding. The debris here seems to be mainly Bridport Sands without much or any Inferior Oolite. Similar cliff falls occur from time to time at East Cliff, West Bay , although rock piles on the beach are usually smaller at that locality.

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BR2 - BRIDPORT SAND FORMATION - SEDIMENTOLOGY

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For more information on sedimentology of the Bridport Sand Formation, please go to the Sedimentology part of the East Cliff, West Bay, Bridport webpage: -

BRIDPORT SANDS - SEDIMENTOLOGY (START).

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BRIDPORT SANDS:

Sedimentary Structures and Trace Fossils - Burton Cliff

(this section has also been added to the: Bridport Sands East Cliff, West Bay webpage.)

Arenicolites, worm burrows, in a bed near the junction of the Bridport Sands and the Inferior Oolite, Burton Bradstock, Dorset, 2010

Sedimentary structures in the Bridport Sands at Burton Cliff, Burton Bradstock, Dorset

A channel structure in the Bridport Sand Formation, lower part, at Burton Cliff, Burton Bradstock, Dorset, 3rd August 2012

Ripple cross-bedding in a channel structure of the Bridport Sand Formation, Burton Cliff, Burton Bradstock, Dorset, 3rd August 2012

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B3a BRIDPORT SANDS - PALAEONTOLOGY AND FAUNA

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For information on the palaeontology of the Bridport Sand Formation, please go to the Palaeontology part of the East Cliff, West Bay, Bridport webpage: -

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BRIDPORT PALAEONTOLOGY.

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B3a BRIDPORT SAND FORMATION

Fossils - Belemnites and Ammonites

A belemnite guard in the lower part of the Bridport Sands, West Bay, Bridport, Dorset, 7th April 2009

<I>Leioceras opalinum</I>, a species of ammonite present in the uppermost Bridport Sands, Dorset

The Bridport Sands are very bioturbated. Thus Trace fossils are common, and may be seen weathered out in the honeycombe weathering (particularly Thalassinoides). Body fossils are not easily found, except for belemnite guards. Belemnites are well-preserved because of the calcite mineralogy, which is relatively stable in meteoric water (providing, of course, there is no acidic dissolution). Aragonite is the mineral component of most most bivalve shells, except oysters and some members of the Scallop family. Gastropods have aragonitic shells. Ammonites, which also have aragonitic shells, are present, but usually only as internal moulds without preservation of the aragonite shell (and usually without neomorphic replacement by calcite in these strata). Ammonites are not very easy to find, but the opportunities for discovery are greater at the top of the sequence near to the Inferior Oolite (where there is more calcareous and somewhat condensed sequence).

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BR3b - BRIDPORT SANDS

Fossil Collecting

The cliffs of West Dorset, particularly the clay cliffs are famous for their fossils. The section at West Bay described here is not usually a place for large-scale collecting. Those interested in fossil collecting from any part of the coast under National Trust and Charmouth Parish Council Ownership between Lyme Regis and Hythe Beach at Burton Bradstock, should consult the fossil collecting code of conduct for that area.

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I0 - INFERIOR OOLITE - STRATIGRAPHY AND SEDIMENTOLOGY

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INFERIOR OOLITE:



INFERIOR OOLITE:

Introduction

A very fossiliferous, fallen block of Inferior Oolite limestone, with belemnites, at the foot of the cliffs at Burton Bradstock, Dorset, October 2009

For a listing of the beds and thicknesses see the vertical succession section given below. A general description and specific aspects of interest in the Inferior Oolite will be discussed here.

This limestone is normally seen when material from the top of the cliffs has fallen, as shown here. The Inferior Oolite is not usually safely accessible in situ. This is not a problem, however, because large blocks of limestone fall and most of the units of the Inferior Oolite are recognisable. Some blocks are a little difficult to identify, though. If you encounter a large block, look for a conspicuous feature like the snuff boxes, and then decide which way up the block is. This fall has brought down Inferior Oolite blocks. At the top of the cliff there is Fuller's Earth visible above the limestone.

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INFERIOR OOLITE:

Burton Lane Section

Burton Lane, Burton Bradstock, Dorset, with overgrown banks where once the Inferior Oolite was well-exposed

In the past there was a good exposure of the Inferior Oolite in Burton Lane. This locality is south of the village and is a lane leading from the garage (SY 487983) southward towards the cliff top. The Bridport Sands can be seen behind the garage and are also exposed at present in places in the lane. Unfortunately, at the time of writing (August 2012) the Inferior Oolite is not exposed in the lane, but is overgrown. The lane is has houses on both sides and is not a place for hammering. It used to be used as a reference section for the stratigrahy of the Inferior Oolite. Richardson (1928) described the section.

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INFERIOR OOLITE:

Succession - Introduction

Middle Jurassic Zonal Listing

(Note: This is given mainly for reference for use with following diagrams, photographs and text. This particular version is based on House (1993) and from time to time might need updating. It is an ammonite zonal scheme, and some of the ammonites, like Kosmoceras jason and Parkinsonia parkinsoni are well-known to geologists in general; some uncommon forms are not familiar to other than specialists.)

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CALLOVIAN (top of MJ, with UJ Oxfordian above)

Quenstedtoceras lamberti
Peltoceras athleta
Erymnoceras coronatum
Kosmoceras jason
Sigaloceras calloviense
Macrocephalites macrocephalus

BATHONIAN

Clydoniceras discus
Oppelia aspidoides
Proceratites hodsoni
Morrisiceras morrisi
Tulites subcontractus
Proceratites progracilis
Asphinctites tenuiplicatus
Zigzagiceras zigzag

BAJOCIAN
[Note, for reference, that in old accounts (eg. Arkell, 1933) the Bajocian zones are from bottom to top: Strenoceras niortensis, Garantiana garantiana, Strigoceras truellei, Parkinsonia schloenbachi.]

Parkinsonia parkinsoni [Parkinsonia schloenbachi]
Strenoceras garantiana [Garantiana garantiana]
Strenoceras subfurcatum [Garantiana subfurcatum]
Stephanoceras humphriesianum
Emileia sauzei [Otoites sauzei]
Witchellia laeviuscula
Hyperlioceras discites

AALENIAN

Graphoceras concavum [Ludwigella concava]
Ludwigia murchisoni
Leioceras opalinum

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[base of Middle Jurassic. Zone of Dumortiera levesquei of the top Toarcian (Lower Jurassic) lies beneath.] [note: that in old accounts there was once a zone of Ancolioceras and a zone of Tmetoceras scissum below the Ludwigia murchisoni zone.]

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The thin, condensed, Inferior Oolite sequence at Burton Bradstock, Dorset, based on Richardson (1928) and partially updated

The top part of the Inferior Oolite near the northwestern end of Burton Cliff, and near Burton Freshwater, Burton Bradstock, Dorset, 3rd August 2012

The locations of the Bajocian unconformity and the snuff boxes in the Inferior Oolite at the top of the cliff at Burton Bradstock, Dorset, 2009

The Inferior Oolite succession in the top of Burton Cliff, Burton Bradstock, Dorset, 3rd March 2008

Some brief comments on the succession shown in the diagram above and in the cliffs are given below. They are based on the summary in Davies (1956) , Perkins (1977) and House (1993) and these in turn are modified from the early work of Buckman (1910) and Richardson (1928) . This is a condensed sequence and full of non-sequences or disconformities (Footnote - In plain language this means that the sequence is much thinner than normal - "condensed"; and there were many gaps in deposition - "non-sequences" , often with some erosion on the seafloor ). The thickness here of nearly 4 m. contrasts with the 110m in the Cotswolds. The reason that it is condensed here is that it is on a structural "high" almost on the east-west line of the Wytch Farm oilfield high. Offshore it is much thicker, 19.3m in Lyme Bay ( Penn, Dingwall and Knox, 1980 ). The sequence seen at Burton Bradstock should be recognised as abnormal, and not a typical Inferior Oolite succession. It is so condensed, that it is reminiscent of the Lower Jurassic, Junction Bed at Eypemouth. It is probably the result of an early phase of the Late Kimmerian movements (extensional - pre the development of the North Atlantic Ocean).

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INFERIOR OOLITE:

Succession - Listed Sequence (top-down)

Fuller's Earth Clay (at the top)
The lower part of the Fuller's Earth Clay, 0.61m seen, with about 0.09m of ferruginous marl, the Scroff, at the base; both yielding Oppelia fusca and "Perisphinctes".

Upper Bajocian

The First Bed, including the Zigzag Bed
(note the quarrymen's method of numbering down)
Blue-centred nodular limestone. Ammonites - Zigzagiceras zigzag, Oppelia and Parkinsonia. Belemnopsis, bivalves and gastropods. 0.15m.

The Second Bed, including the Sponge Beds
Massive yellowish limestone with much brown earthy matter. Ammonites are often rotten. Stout Parkinsonia, Terebratula, Rhynchonella and sponges. This is divided as follows:
Massive limestone - 0.63m.
Sponge Beds - Marl with two limestone partings, crowded with sponges, Clypeus, brachiopods, bivalves - 0.36m
Rubbly limestone with similar fossils, including large Nautili - 0.40m.

The Third Bed
Limestone divided as follows:
Blue grey limestone, rubbly top, attached serpulids, the brachiopod -Sphaeroidothyris sphaeroidalis, the echinoid - Clypeus, and bivalves - 0.56m.
Astarte 'obliqua' Bed. Crumbly brown ironshot limestone crowded with fossils. - 0.10 m (including the impersistant conglomerate beneath)

Lower Bajocian

The Red Bed, sensu lato

- a little less than one metre and comprising the subdivisions listed below

Scissum Bed to Red Bed Sequence of the Inferior Oolite in a fallen block at Burton Cliff, Burton Bradstock, Dorset

Red Conglomerate. Conglomerate of ironshot rock, patchily present with poorly preserved ammonites. - Thin and of variable thickness. Remanie bed of the Stephanoceras humphresianum Zone. 0-0.14m.

Red Bed, sensu stricto. Hard massive grey limestone, the top irregular and stained red with iron (including at the base - limestone with brownish limonitic granules. - 0.18m.). Zones of Witchellia laeviuscula and Emileia sauzei (above). Early laeviuscula is represented by a diastem (non-sequence) ( House (1993)). - 0.8m (thickness in Burton Lane)

Snuff Box Bed. Limestone, bluish, limonitic ooids and large limonitic concretions, the snuff boxes, near the base. Hyperlioceras discites Zone. Ammonites - Stephanoceras, Witchellia, Sonninia. - 0.08m.

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Aalenian

Yellow Conglomerate. Yellow marl with small pebbles and rolled fossils, reworked and eroded from earlier strata. - 0.04m.

Scissum Beds (or Bottom Bed). Grey sandy limestone with the ammonite Tmetoceras scissum. Effectively the top of the Bridport Sands - 0.30m.

Bridport Sands (part). - about 0.2m? (see Richardson, 1928 and House, 1993 re the Burton Lane section inland of the cliff)

Toarcian

Bridport Sands below (thick).

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INFERIOR OOLITE:

More Details

A horizontal section through a snuff box of the Red Bed of the Inferior Oolite at Burton Cliff, Dorset, March 2008

Ironshot oolite in the Red Bed of the Inferior Oolite at Burton Cliff, Dorset

This is a fallen block of the Snuff Box horizon of the Red Bed, perhaps the most well-known stratum of the Inferior Oolite here. This bluish, "ironshot oolite", only 8 cm thick, is easily recognised by the large, brown, limonitic concretions, known as "snuff boxes". The limonitic ooids, which it contains, are quite large and conspicuous.

Green, iron-rich mineral in cliff-fall debris of Inferior Oolite, Burton Bradstock, near, Bridport, Dorset

The strata are largely oxidised at the surface and most iron is in the state of limonite. Offshore, to the south in Lyme Bay, the Inferior Oolite is thicker (19.3m) and here much berthierinte ("chamosite") is present in addition to limonite in the succession ( Penn, Dingwall and Knox, 1980 . It should not, therefore, be assumed that the snuff boxes and associated ferruginous strata were always in brown oxidised condition. The recent cliff fall has revealed that green iron minerals still survive, as shown in the photograph above. This green substance has not be investigated yet to determine whether it is the green iron-ore berthierine (as is more probable) or is the iron-bearing clay mineral - glauconite.

The snuff boxes seem to be formed of algal stromatolitic (microbial) laminations of unusual ferruginous type centred around bivalve shells and other nuclei ( Gatrall et al ., 1972 ; Radley, 1986 , Palmer and Wilson, 1990 ) They have been regarded as a type of oncolite (or oncolith). They occur within in the zone of Hyperlioceras discites of the basal Bajocian. Ammonite found in this bed include species of Stephanoceras, Witchellia and Sonninia. (Photograph by Gareth Lloyd, 27.7.96).

Sponge Bed

This fallen block of Inferior Oolite limestone is probably from the Sponge Bed. The Sponge Bed is a marl with two limestone partings, crowded with sponges, the echinoid Clypeus, brachiopods and bivalves etc. It is 0.36m in thickness. It is from the higher part of the Inferior Oolite, the Upper Bajocian. See the section on succession .

[end of 3.3 Inferior Oolite - Details]

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INFERIOR OOLITE:

Ammonites

Ammonites found by LSBU students in a rock fall of Inferior Oolite at Burton Bradstock, near Bridport, Dorset, April 2005

Ammonites from a rock fall of Inferior Oolite at Burton Bradstock, near Bridport, Dorset, April 2005

Ammonites are quite numerous in the condensed sequence of the Inferior Oolite at Burton Bradstock. They are not usually easy to find, though because of limited amounts of the limestone at beach level and because collectors have taken specimens. They are not as well-preserved as the ammonites of the Liassic clays, but have considerable stratigraphical significance. After a rock-fall from the cliff in April 2005 ammonites and fragments of ammonites were common in the debris. However, this rock debris has been searched by many collectors the fall and there is little that remains now.

Ammonites from the Lower and Middle Inferior Oolite. Modified from Arkell (1933) , Plate 33. The first number after the name and location information is the maximum diameter in millimetres (useful here to give the scale), the second the height of the last whorl, the third the thickness of the last whorl, the fourth the width of the umbilicus.

Ammonites of the Lower and Middle Inf. Oolite

1. Shirbuirnia stephani Buckman, Sandford Lane, Near Sherborne, Dorset. Chorotype J.W.T. collection. 117. 51.31.18.

2. Hyperlioceras discites (Waagen) pars., H. discitiforme Buckman. Bradford Abbas, Dorset. Topotype. J.W.T. collection. 65. 50.20.13.

3. Ludwigella concava (Sowerby), Wyke, near Sherborne, Dorset. J.W.T. collection. 71. 52.21.15.

4. Tmetoceras scissum (Benecke), Burton Bradstock, Dorset. J.W.T. collection. 35. 33.28.45.

5. Brasilia bradfordensis Buckman, Barrofield, Beaminster, Dorset. J.W.T. collection. 123. 48.21.21.

6. Ludwigia murchisonae(Sowerby), Bradford Abbas, Dorset. From Buckman "Monograph Ammonites Inferior Oolite, plate 3, fig. 1. 114. 41.26.32.

Ammonites from the Middle and Upper Inferior Oolite. Modified from Arkell (1933) , Plate 34. The first number after the name and location information is the maximum diameter in millimetres (useful here to give the scale), the second the height of the last whorl, the third the thickness of the last whorl, the fourth the width of the umbilicus.

Ammonites of the Middle and Upper Inf. Oolite

1. Parkinsonia schloenbachi Schlippe, Burton Bradstock, Dorset. G.A. Kellaway collection. 75. 34.33.44.

2. Garantiana garantiana (d'Orbigny), Near Sherborne, Dorset. J.W.T. (J.W. Tutcher) collection. 76. 38.34.36.

3. Strigoceras truellei(d'Orbigny), Burton Bradstock, Dorset. J.W.T. collection. 79. 56.36.7.

4. Strenoceras niortensis (d'Orbigny), Oborne, Dorset. J.W.T. collection. 40. 35.30.41.

5. Teloceras blagdeni (Sowerby), Near Sherborne, Dorset. J.W.T. collection. 41. 29.71.47.

6. Otoites sauzei (d'Orbigny), Dundry Hill, Somerset. J.W.T. collection. 36. 42.50.23.

[end of 3.4 Inferior Oolite - Ammonites]

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3.5 INFERIOR OOLITE - Other Fossils

Fossils of the Inferior and Great Oolite

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FULLERS EARTH



STRATIGRAPHY:

FROME CLAY OR UPPER FULLERS EARTH ETC

Burton Cliff East near Bridport, Dorset

As noted above, west of the car park the Bridport Sands are exposed in vertical cliffs. However, the Bride Fault disturbs the Bridport Sands where the path climbs to the cliff top to the west. Visible here in the past, and associated with the fault, were white limestones which may indicate the presence of a contemporary fissue (neptunian dyke) of Bajocian date within the Bridport Sands ( Richardson, 1928-30 ). The Bride Fault belt downthrows 60m south and introduces the Middle Jurassic to the east. The grey calcareous mudstones of the Frome Clay or Upper Fullers Earth are seen in sloping and rather slumped cliffs. They are not in general very fossiliferous. These mudstones are not laminated and more resemble the Eocene Barton Clay (without the fossils) or the Jurassic Oxford Clay (again with less fossils) than they do the laminated Liassic or Kimmeridge Clays.

About 200m to the east of the car park the Boueti Bed, a thin calcareous and harder band, can be traced in eroded ground between the footpath and the cliff top and it yields the brachiopods Goniorhynchia boueti, Avonothyris, Digonella, with bivalves and other fossils. In the cliffs below the upper part of the Fuller's Earth Clay can be examined and it crops out in the low cliffs at Burton Common and Cliff End (SY 499883) (House, 1993).

The cliffs to the south-east towards the Abbotsbury Fault are much receded, landslipped and overgrown and are not particularly favourable for examination. However, fossiliferous outcrops of the Forest Marble were recorded by Sylvester-Bradley (1957).



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BURTON CLIFF - WELL-KNOWN SITE OF ROCK FALLS

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BURTON CLIFF AND ROCK FALLS

Introduction

Map showing the occurrrence of vertical cliffs at Bridport and Burton Bradstock, Dorset, 2006, redrawn after Callway (2009)

[Historic note about cliff falls in Bridport area in 1890 by the Rev. H.S. Solly.

"In wet weather the water falling on the surface of the cliffs cut deep gullies, while high tides undermine the base. Huge overhanging masses, therefore, fall from time to time, often in hot dry weather throwing up clouds of dust. The fallen material is rapidly removed by the sea." ]

[The reference, though, is to the cliff west of Bridport, rather than east; the western cliffs at that date also included some Bridport Sands]

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A barrier and an advisory notice regarding rock falls at Burton Cliff, Burton Bradstock, Dorset, at the Hive Beach end, 3rd August 2012

A photograph of a rock fall at Burton Cliff in November 2002, by Alan Holiday, compared to a photograph of the site of the fatal rock fall of July 2012

Burton Cliff is the most well-know locality in Dorset for rock falls. It may have the most photographed numbers of rock falls for anywhere on the British coasts (although not highest number of falls). Geologists have been coming to Burton Cliff to see the results of rock falls for more than 100 years. They come from all over the country and often travel here from abroad. Accidents do not generally happen on old rock fall debris cones. When the fall has taken place and some time has passed the risk on the debris cones may be less than at the foot of a vertical cliff.

In spite of the regular use of rock fall debris cones, Burton Cliff may not necessarily be a peak rock fall locality; it is simply that the occasional rock falls leave conspicuous debris of considerable geological interest, and material that cannot be easily access anywhere else now (local small quarries no longer exist). The rock falls seem at present to be taking place about once or twice a year. Photographs go back to at least 1928 and there may be earlier ones in existence. However, the full record is not known and the photographic evidence is patchy and dependent upon the dates of field visits to the locality.

In comparison, Lulworth Cove and adjacent area has had more fatalities (five) from rock falls in recent years, and thus appears statistically more hazardous. East of Kimmeridge Bay is a place where there are many small rock fall and occasional larger one. At the Lyme Regis cliff exposures individual rocks and some larger masses fall from time to time, and sometimes fall close to people. The photographs below show examples of rock falls at Burton Cliff, but many have been missed, as they only happen on relatively rare occasions of about six months or a year intervals. However, if you are present at a particular part of the beach on a particular day you might be at risk.

Buton Cliff has long been known for rock falls because this is only way that geologists gain access to the Inferior Oolite which is in the top of cliff. They have for a century or more examined the fallen blocks at debris cones adjacent to the cliffs. Very sadly a rock fall, seeming to be of the normal type for Burton Cliff, was responsible for a fatality on the 24th July 2012.

There is risk at the base of the cliff, but the extent of risk is affected by the length of time spent there and the number of people who walk or sit close to the cliff. It is better to walk closer to the sea and away from the cliff as far as possible. Geologists should not spend long at the cliff, confining themselves to brief visits. If there are few people on the beach then, statistically the risk of a fatal accident is low.

It is possible, but unproven, that rock falls are increasing in frequency at Burton Cliff. A factor here might be loss of shingle from the beach. This is near the western end of the Chesil Beach and is no longer receiving much sediment from the west. Bridport Harbour at West Bay has long had large sea walls obstructing sediment movement. Shingle has been worked and removed from the beach on the east side of the harbour for many years. This was once quite an industry, removing natural beach material.

Coastal squeeze, the process whereby the low water mark approaches the high water mark in geographical terms (horizontally not vertically) might be another factor. This is the result of sea-level rise.

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[SUPPLEMENTARY NOTES]

Burton Cliff Accident - Similar Accident at Rothesay Bay, New Zealand.

(Strata - East Coast Bays Formation, Waitemata Group - Miocene)

Comparion of rock falls at Burton Bradstock, Dorset, England, 2012 and Rothesay Bay, New Zealand, 2011

A fall of rock from horizontal sandstone took place at Rothesay Bay, New Zealand on the 7th July 2011, about a year before the Burton Bradstock accident. Sadly, a lady was also killed in the New Zealand case by the rock fall. The rock fall may have been much smaller than at Burton Cliff but there are geomorphological and other similarities. In both cases the cliff was about 40m high and vertical. In both cases the strata were horizontal. Both the people involved were walking on the beach fairly near the foot of the cliff. Note that cliffs are rather more likely to have vertical faces if they contain horizontal well-bedded strata.

Extract from Press Article

"Rockfall death: danger always existed

By Hayden Donnell
4:12 PM Thursday Jul 7, 2011

Rothesay Bay on Auckland's North Shore, where a woman, Inna Rudyy-Collie, died after being hit by falling rocks. Photo/ Paul Estcourt

Erosion caused by residents' stormwater drain runoff was not behind a fatal rockfall at an Auckland cliffline, a geotechnical report has found. Inna Rudyy-Collie, 44, died after being struck by falling rocks while walking her two dogs on Rothesay Bay beach on Saturday. Auckland Council checked drainage at 40 clifftop properties and asked for reports on the stability of the area in the wake of her death. A Tonkin and Taylor geotechnical report released today said rockfall danger had "always existed" in the area around Rothesay Bay. It found no evidence to suggest erosion caused by water discharged from stormwater drains in the cliffs had caused the fatal fall. Weak rock was widespread throughout the East Coast Bays and measures to shield the public from danger along its seaside cliffs would be difficult to implement, it said.
"The recent accident is indeed tragic and to our knowledge is the first known fatality of its type in Auckland. The coastline is used by people at mid to low tide, and the measures required to secure the public from injury from rockfall right up to the foot of the cliff would be extensive, expensive and difficult to construct."
Tonkin and Taylor recommended putting up signage warning walkers of the "minor" danger posed by the cliffs.

Auckland Council spokesman Glyn Walters said many of the old North Shore City Council rockfall warning signs had fallen down or been vandalised. Officers were putting up new signs and council was considering an information campaign informing residents of the danger. Hibiscus and Bays local board last night passed a resolution offering its condolences to Ms Rudyy-Collie's family and calling for a public awareness campaign on the rockfall danger in East Coast Bays. Council chief operating officer Patricia Reade earlier urged beachgoers to stay 10m from the cliff, especially at high tide when walker were forced closer to the face. While the rockfall was typical of the natural erosion on Auckland's east coast, the council is considering a wider investigation of the city's cliff-faces after the accident. Auckland's east coast cliffs have been eroding at a rate of two to six a century for the past 10,000 years. This is a much faster rate than the west coast, where erosion is negligible in comparison. The east coast erosion is partly due to increased development, but also the geological conditions - most of the cliff-face is made of soft and brittle sandstone and mudstone.
- Additional reporting by Isaac Davidson"

For more information go to:

Council warned about unstable cliffs - residents.

Published: 7:13AM Monday July 04, 2011 Source: TVNZ ONE News.
Residents of the Auckland suburb where a woman was killed by a rockfall say the council has been warned about dangerous cliffs. Inna Viktorovna Rudyy, 44, was killed on Saturday afternoon in Rothesay Bay, on Auckland's North Shore, when she was hit by rocks which fell about 100m from the cliffs above. [continues].

Emergency Geotechnical Inspection of Rockfall, Rothesay Bay Cliffs, Auckland. ]

[END OF SUPPLEMENTARY NOTES]

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BURTON CLIFF AND ROCK FALLS

Comparison - The Lulworth Cove Rock Fall, 1977.

Sadly, rock-fall accidents occur on the Dorset coast from time to time. In the late 1970s there was a spate of fatal accidents. The worst of these was at Lulworth Cove, and this had some similarity to the Burton Cliff rock-fall in 2012. It was reported in detail in the press. (See also Lee (1992) p. 80, quoting newspaper reports).

There was a fatal accident by a rock fall at Lulworth Cove to three school students and a teacher in 1977. For more information see the Geology of Lulworth Cove, East webpage. Here are newspaper reports of the accident and the desperate rescue attempt, which enabled the resuscitation in a helicopter of one person.

Cliff-fall accident at the southeast corner of Lulworth Cove, Dorset in 1977

Cliff-fall accident at the southeast corner of Lulworth Cove, Dorset in 1977 - continued

Newspaper Report of the Accident at Lulworth Cove
(Bournemouth Evening Echo, Feb. 21st 1977 - extract only - see the full article above)

The group had walked around the Lulworth beach to the East Point of the cove, and Miss Taite had stopped them under the 75-foot-high cliff to point out the rock structure. They were drawing this in their notebooks when the cliff suddenly gave way. Tons of rock debris and clay fell onto the party and two were buried. Mark Pleydell ran a mile along the beach to the cafe to call for help, while the other three who were not badly injured, started to dig out their classmates.
Ambulance, police and coastguards rushed to the scene, and two helicopters were sent from Lee-on-Solent.
"The rescue was a tremendous effort" commented Chief Inspector Daubeny.
"The ambulancemen tended to the injured on the beach without once looking up to the dangerous state of the cliffs above them"

[article continues]

.

In comparison, two views of the rescue operation at Burton Cliff have been given in a BBC article on the web. See the article online.

See: Criticism Over Dorset Landslide Death.

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BURTON CLIFF AND ROCK FALLS

Comparison - More Dorset, Cliff Fall Accidents

Other rock fall accidents have happened on the Dorset coast. A man was killed a few years ago by a rock falling at Stair Hole, Lulworth Cove. Back in 1979 a woman was killed on the beach at Durdle Door when a 3m overhang collapsed (Upper Greensand fall?). In 1971 a nine year old girl was hit by a falling rock at Kimmeridge and later died of her injuries. A schoolboy received brain injury from a falling rock in Durlston Bay, Swanage in 1975. In the more distant past 9 people went to hospital after a fall of chalk at Black Rocks, Lulworth Cove on the 8th July 1957. Fortunately no-one was killed.

From time to time, there are various "near-misses" and most geologists will have had rocks fall near by them at some time or another. Many years ago, a field party was just missed by a large cliff collapse of Belemnite Marls between Charmouth and Golden Cap. A landslide between Charmouth and Golden Cap happened on Wednesday 8th August 2012 according to the press; it was seen from a boat. Five people on the beach were led to safety.

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BURTON CLIFF AND ROCK FALLS

Dorset Cliff Fall Risks - Comparison with 1977.

In the 1970s there was a phase of various rock falls and landslides. These were discussed in the press. The events changed geological field work, which became more restrictive in various ways, with parties normally wearing safety helmets after the 1977 accident, referred to below. These can provide protection against very small rocks but, of course, are of little use with regard to major rock falls.

See: Evening Echo, Bournemouth, 21st February 1977.

New warnings after cliff fall tragedy.

Warnings came today about the "killer cliffs of Dorset" after yesterday's tragedy at Lulworth Cove when a landslip engulfed a school party in tons of rock and clay, killing a teacher and teenage pupil and seriously injuring two others [one of whom subsequently died].
"These cliffs are completely unstable for virtually the whole length of the coastline from Swanage to Ringstead" said Chief Inspector Richard Daubeny of Wareham police after he had helped dig out victims of the fall at East Point, Lulworth Cove. "No-one should go near them"
"It is difficult to tell people not to go near the beauty spots." he added "but we will do everything we can to keep tourists away from the edge of the cliff or anywhere close to them. They must make sure that they look at the cliffs at a distance."
"These cliffs are killers, particularly this year after the torrential rain of the last few months." .. [continues..].

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BURTON CLIFF - ROCK FALLS - YEAR BY YEAR
BURTON CLIFF AND ROCK FALLS

YEAR - 1928

Rock fall at Burton Cliff, Burton Bradstock, Dorset, in 1928

Burton Cliff is a coastal feature that is dependent on rock falls and sea erosion to maintain its characteristics. The falls are not frequent but have been taking place almost every year and will continue to do so. The photograph above, courtesy of BGS Geoscenic, shows they were happening in 1928; of course they have been occurring for thousands of years before. They are normal for this stretch of coast, although there is discussion about whether they are increasing in frequency now. A limited area of Bridport Sand cliff has been completely destroyed by the sea on the west side of Bridport Harbour, West Bay. East Cliff, West Bay has rather similar geology to that of Burton Cliff (but without good development of Inferior Oolite) but has less rock falls at present, probably because of a wider beach. At a later stage this may become similar to Burton Cliff.

Some later records of rock falls at Burton Cliff now follow.

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BURTON CLIFF AND ROCK FALLS

YEAR - 1956 and Earlier

April 1914 - Easter Field Excursion of the Geologists' Association to Bridport etc. ( Richardson, 1915)

"During a walk along the beach to the place where the huge masses of Oolite have fallen bodily down, the precipitous cliffs of Bridport Sands, capped with Oolite and Fullers' Earth, were much admired. The position of the Red Bed could be easily made out by its red stain."

Loading a cart on the beach at the Burton Hive end of Burton Cliff, Burton Bradstock, Dorset, in about 1930

Two old rock falls at Burton Cliff shown by Davies (1956), including geologists studying the fallen Inferior Oolite

Rock falls at Burton Cliff have long been known to geologists. The old photograph above shows geologists at work on Inferior Oolite blocks at rock falls. I have, of course, used rock falls to examine the Inferior Oolite from 1960s or earlier. It has been the usual custom for studying the otherwise inaccessible strata cliffs in this area, as shown by the extract above from a Geologists' Association field excursion in 1914.

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BURTON CLIFF AND ROCK FALLS

YEARS - 1996 - "Pillar Rock", near the mouth of the River Bride

An photograph of a rock fall, probably from 1996, at the western end of Burton Cliff, Burton Bradstock, Dorset, with a wider beach present at that date, by Gareth Lloyd

Children play on a rock fall near the Western Endo of Burton Cliff, near Burton Freshwater, Burton Bradstock, Dorset, July 1996

This location of this old rock fall, referred to here for convenience as "pillar rock" is a short distance to the southeast of the mouth of the River Bride at Burton Freshwater. The cliff of Bridport Sand Formation here is lower as the top slopes down to the river. There is no Inferior Oolite in the cliff just here. The image above shows the remains of a cliff fall as seen at 27 July 1996 soon after the collapse. There are many angular, joint-bounded blocks of Bridport Sands and much loose sandy debris. Presumably the blocks are from the more cemented horizons, and the poorly cemented sands between have provided the loose debris.

A rock fall of Bridport Sand Formation near the northwestern end of Burton Cliff, Burton Bradstock, Dorset, in the late 1990s

Above is another older photograph (about 1996 or 1998) of the pillar rock fall towards the northwestern end of Burton Cliff. The rock fall is of the usual type, with vertical collapse and a debris cone on the beach. Even though the cliff is lower here the debris cone is quite impressive.

Apart from rock falls, the erosion of the cliffs in this northwestern area is unusual. Some of the harder bands are very well cemented and relatively resistant to marine erosion. This has resulted a residual projecting platform near the top of the beach. This was probably once protected by beach sand. Notice how the sandstone has been weathered along nearly vertical joints. At the western end of Burton Cliff, at the date of photograph, there have probably been few cliff falls but much erosion has been by rain, wind and spray so as to produce this unusually gullied cliff.

In the late 1990s the beach at the northwestern end of Burton Cliff seemed quite wide in the area of the pillar rock fall.

The pillar rock fall site of 1996, seen on 3rd August 2012, near the northwestern end of Burton Cliff, Burton Bradstock, Dorset

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BURTON CLIFF AND ROCK FALLS

YEAR - 1996 - July - Substantial Rock Fall in Central Area

A major rock fall at Burton Bradstock, Dorset, in 1996 and involving Bridport Sands, Inferior Oolite and Fullers Earth

The rock fall shown above was photographed by Gareth Lloyd on the 21st July 1996 and it seems very fresh in the image, without much erosion or weathering. This was a large rock fall in the central part of Burton Cliff and involved not only Bridport Sand Formation but also the Inferior Oolite and the Fullers Earth. There is a gull (joint probably enlarged during the Pleistocene) on the right hand side (southeast side). Some large flat slabs of Inferior Oolite seem to have split in jigsaw manner as in the case of the 24th July 2012 rock fall.

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BURTON CLIFF AND ROCK FALLS

YEAR - 2002 November Rock Fall

Rock fall in November 2002 at a site close to that of the fatal 2012 rock fall, Burton Cliff, Burton Bradstock, Dorset, photograph by Alan Holiday

In 2002 an area of prominance in the central to northwestern part of Burton Cliff had a significant rock fall. The site is probably within 50 or 100m of the fatal rock fall site of July 2012. I am grateful to Alan Holiday for the photograph shown above. It is clear that there have been other rock falls in this area. An older rock fall is indicated by blocks of Inferior Oolite (the Red Bed) with weathered, whitened top surfaces. In addition the photograph seems to show, in the distance, some rock fall debris in or almost in the area of the 2012 fall. The photograph is useful in that it now fixes the location of a cliff scar of 2002.

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BURTON CLIFF AND ROCK FALLS

YEAR - 2005 CONTINUED - 9th April

A large rock fall with Inferior Oolite and Fullers Earth, Burton Bradstock, Dorset, 2005

Members of the public explore the rock fall at Burton Bradstock, Dorset, in April 2005

Cliff fall at Burton Bradstock, east of West Bay, Bridport, Dorset, 9 April 2005

Fissures at cliff fall, Burton Bradstock, April 2005.

This fall of Bridport Sands and Inferior Oolite took place in the late afternoon of Saturday 9 April 2005. The weather had not been particular wet or unusual in any respect. It was not a rotational landslide. It seems to have been a collapse of rock due to undercutting of the Bridport Sands at beach level. This is the result of wave action causing abrasion by the beach shingle. Bioerosion is not significantly involved here.

The type of rock fall is rather like that seen on vertical or near-vertical Chalk cliffs. It resembles the Category 1a, Simple vertical collapse, of Chalk cliffs of Mortimore et al (2004). These simplest cliff failures are vertical collapses where there is usually one formation (but slightly more complex here with the Inferior Oolite above a high cliff of Bridport Sands). A predominant set of joints controls the type and scale of failure. Certainly there is joint control here, but it is a set parallel to the cliff and not the major open gulls which are at a steep angle to the cliff.

There are two complications. One is that there is undercutting at the base of the cliff. This sometimes occurs in the case of Chalk. The second is that there has "runout" on a significant scale. The rock debris has run-out to the sea, but has not reached the scale of a small sturzstrom run-outs [mountain rock falls with very long run-outs], as has happened at the Seven Sisters in Sussex ( Williams et al., 2004). Because of this run-out the rock fall approaches Category 1c, Large rock falls involving entire cliff (partial flow slides) of magnitude 5-7 Mortimore et al (2004). No detailed study has been made, but perhaps some-one will follow the matter further and refine the classification and type of rock fall here.

The occurrence of many Inferior Oolite limestone blocks near to the sea with Bridport Sands blocks closer to the cliff suggests that it fell with some seaward toppling mechanism but distingrated violently into individual blocks of about 2 metres or so. The fallen mass was presumably separated from the main cliff by a fissure; fresh modern, vertical, fissures as opposed to older joints are visible in the cliff in places and obviously indicate areas of potential collapse.

Some older worn blocks of Inferior Oolite are present near the toe of the debris pile. Thus this has been the site of a previous rock fall or rock falls.

From a point of view of safety, such falls are obviously sudden and unpredictable and take place only at intervals of several years. They are clearly sudden events that would be disastrous to any people who happened to be at the location at that time. [long since this was written such a sad event has indeed occurred with a fatality at Burton Cliff on the 24th July 2012.]

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BURTON CLIFF AND ROCK FALLS

YEAR - 2005 - Undercutting and Future Threat of Rock Falls

Undercutting and cave development at base of fissures, Burton Bradstock Bridport, Dorset

Cliff-fall hazard at Burton Bradstock, Dorset

Shown above are photographs from 2005 that indicate an unstable cliff to the west of Hive Beach, Burton Bradstock. There has been undercutting in this area, and there are major open joints which have long caused the cliff to be weak and ready for failure.

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BURTON CLIFF AND ROCK FALLS

YEAR - 2007 - Storm

Photograph of rough sea at Burton Cliff, Burton Bradstock, Dorset, by Alan Holiday in 2007

Erosion of a rock fall debris cone at the southeastern end of Burton Cliff, Burton Bradstock, Dorset, in December 2007, photographed by Alan Holiday

Photographs of the Burton Bradstock area above, taken by Alan Holiday, show a very stormy sea with a wave pattern of long-wavelength. At Burton Cliff the sea is washing right up to the base of the cliff. A debris cone from a rockfall is shown being eroded by the sea. The debris cones are not permanent and are removed almost completely after a while. Sometimes a few residual large rocks remain at the foot of the cliff indicating the position of the former rock fall.

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BURTON CLIFF AND ROCK FALLS

YEAR - 2008

A general view of the Bridport Sands, the Upper Reservoir Rock of the Wytch Farm Oilfield, seen here in the cliffs at Burton Bradstock, near Bridport, Dorset, March 2008

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BURTON CLIFF AND ROCK FALLS

YEAR - 2009 - State of Cliff Prior to the 2012 Rock Fall

Walking on the beach beneath Burton Cliff in October 2009 towards the promontory near the site of the later, July 2012, rock fall

A Channel Coastal Observatory aerial photograph of part of Burton Cliff, Burton Bradstock, Dorset, in August 2009

Looking over the edge of the unstable Burton Cliff, near the area of the fatal rock slide in 2012, older photograph of 2009, Burton Bradstock, Dorset

The remains of a rock fall debris cone seen from the cliff top, Burton Cliff, Dorset, and with an inclined block of Bridport Sand Formation

The year 2009 does not seem to have been notable for rock falls at Burton Cliff, although the remains of some rock falls could be clearly seen. Some photographs from that year show the state of the cliff then. The Burton Hive end (i.e. the southeast end) at about this date is discussed separately below.

(On Monday, 21st September 2009, Rebecca Evans in the Daily Mirror reported that a boy of nine was seriously injured when he was crushed by a ton of rocks which tumbled from a seaside cliff yesterday as he played on a beach. This was the Chalk Cliffs at the back (north side) of the cove, probably near Black Rocks where there has been a major rock fall accident in the 1950s.)

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BURTON CLIFF AND ROCK FALLS

YEARS - 2008-2012 - Cliff Changes near Hive Beach

Changes in the cliff west of Hive Beach, Burton Bradstock, Dorset, as a result of rock fall

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BURTON CLIFF AND ROCK FALLS

YEAR - 2012 - February

A rock fall of the 10th February 2012, near Hive Beach, Burton Bradstock, Dorset, Alan Holiday photograph

Rock fall of the 10th February 2012, near Hive Beach, Burton Bradstock, Dorset, Alan Holiday photograph

A view up the rock fall at Burton Cliff, near Hive Beach, Burton Bradstock, Dorset, 19th February 2012

The photographs directly above were taken by Alan Holiday on the 19th February 2012, and record the debris of a cliff fall that had taken place on the 10th February 2012. This is not a safe place and the Bridport Sands are not very fossiliferous, so there is no particular reason to scramble over this. Further falls might occur. The process of periodic cliff falls here is a natural result of wave action undercutting the base of the cliff of Bridport Sands. Other photographs show that this is a place where there is frequently an overhang at the base. The reason for this is that the beach is fairly narrow here and at high tide and particularly in storm conditions the sea reaches the foot of the cliff. The fine shingle is very abrasive and easily cuts out an overhang; in addition there are major joints in the Bridport Sands.

A joint opening in the uppermost Bridport Sands, eastern part of Burton Cliff, near Burton Hive, Dorset, by Alan Holiday, 19th February 2012

This photograph shows a joint at a place where the cliff has not yet fallen. It is a weakness, and at the base of the joint there is a tongue of washed-out sand. Thus rainfall is gradually clearing and opening the joint. Alan Holiday, who took the photograph, mentions that this part of the cliff will fall sooner or later. Notice the darker-coloured sandstone at the base of the cliff (bottom of photograph). This is where undercutting is taken place, and this removes the lighter-coloured and more weathered yellow sandstone.

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BURTON CLIFF AND ROCK FALLS

YEAR - 2012 - ROCK FALL WITH FATAL ACCIDENT, JULY 2012

Sadly, a fatal accident occurred at the sandstone cliffs at Burton Bradstock on the 24th July 2012. There was a large rock fall at cliffs, the base of which is attacked by waves during severe storms. This was at least the second time someone has been killed by fall of sandstone cliffs in the Dorset-Devon region. A similar accident occurred at Dawlish in 1885. Of course the Burton fatal rock fall will not be the last to occur on the south coast.

See also the relevant section of webpage Teignmouth to Dawlish, Devon of which the following is an extract. The cliff is of sandstone above breccia, geological older than that at Burton Bradstock, but with a low dip and considerable similarities. As at Burton Bradstock it was undercut at the base by the sea in storms. [The Dawlish cliff is now much safer, with re-sloping and a promenade].

"On Saturday, August 29th 1885 at around noon, six members of the family and household of Dowager Lady Sawle were preparing for a picnic lunch beneath the overhang, when a large mass of rock (estimated 50 - 150 tons) split from the cliff above them. They had a moment's warning from a seventh party member, Ellie Watson, who was standing nearer the sea and saw the start of the collapse. Three ran towards the cliff, and were buried and killed instantly: nine year old Violet Mary Watson; Mary Radford (lady's maid to Lady Sawle) and Elizabeth Keen (nurse to the Watson children). Three who ran towards the sea, a Miss Watts, Miss Matthews, and Johnny Watson, survived, but were seriously injured. Only Ellie Watson was unhurt."

.

An oblique, foreshortened view of Burton Cliff , Burton Bradstock, Dorset, on the 24th July 2012, soon after a fatal accident caused by a rock fall, new

The fatal rock fall at Burton Cliff in 2012 was the third of three recent rock falls on those cliffs, Burton Bradstock, Dorset

There have been at least three recent rock falls at Burton Cliff. The rock scars and the rock debris on the shore from each is shown in the photograph above. Tragically the last and most recent of the three, at about 12.30 BST on the 24th July caused a fatality. The location is the freshest of the three sites shown here, in a photograph from the sea by Martin Cox, and it the one with the conspicous debris cone extending out across the beach.

Burton Cliff, Burton Bradstock, Dorset, showing the variation in cliff type and the site of the rock fall accident of 24th July, 2012, photo taken 3rd August 2012

Very sadly on the 24th July 2012, there was a fatal accident near the middle part of Burton Cliff. Some people were walking on the beach. According to BBC News Dorset (2012), Witnesses at the beach said Ms Blackman, from Heanor, had been seen walking directly under the cliff. At high tide, at the eastern end this is sometimes necessary, but much depends on weather and wave conditions. In storm conditions the beach is often impassable.

[Tidal Data for Bridport on the 24th July 2012:
(from Tide Times webpage.)

Low tide: 0.34 BST. (0.8m)
High tide: 10.31 BST. (3.80m)
(Accident time - about 12.30)
Low tide: 15.58 (3.58pm) BST. (0.9m)
High tide: 22.45 (10.45pm) BST. (3.9m)

Thus the tidal situation was at about mid-tide at the time of the accident. From photographs the weather conditions seem to have been calm, with little wave action.]

A rock fall, with a rumble and a huge amount of dust then took place. This was the first stage followed by a time gap. In the first rock fall, involving much sand, Ms Blackman, her boyfriend and her father were all buried when the 160ft (49m) high cliff above them collapsed. The men were pulled free by bystanders but they could not locate Ms Blackman.

A second rock fall (about 20 minutes later?) caused deeper burial of Ms Blackman. Later, after excavation work, at 21:40 BST her body was found by emergency workers within the 10m high pile of fallen rocks. Photographs above show that the lower material was mainly Bridport Sand. The upper material which probably represent the later fall is mostly of Inferior Oolite ferruginous limestone. There is a small amount of Fullers Earth debris on top. In other words the sequence in the debris relates to normal stratigraphy here. It seems to be a vertical sequence of Bridport Sand, overlain by Inferior Oolite (part), with some Fullers Earth at the top. The question arises as to whether an initial Briport Sand fall left an overhanging ledge of Inferior Oolite which collapsed in the second rock fall (some Inferior Oolite is still overhanging to some extent.

Photographs show that the rock fall was, in general, of the normal type for Burton Cliff. It was not exceptionally large but included a sequence of debris, mostly Bridport Sands (which forms the greatest part of the cliff) with some Inferior Oolite, and also some grey Fullers Earth (clay). It thus involved the whole cliff from bottom to top. It was, of course, a simple rock fall, as occur commonly here, and not a landslide. It does not seem to have been extreme or unusual in type. At low tide the rock fall does not extend to the sea and seems to occupy only about half of the width of the low-tide beach. It was a normal rock fall for this cliff.

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BURTON CLIFF AND ROCK FALLS

YEAR - 2012 July - Rock Fall with Fatal Accident - Location.

The July 2012 rock fall in relation to a long stretch of eroding cliff to the southeast, Burton Cliff, Burton Bradstock, Dorset

The location of the rock fall at Burton Bradstock, Dorset, in July 2012

The fatal rock fall was not in the most dangerous part of the cliff (nearer to Hive Beach). However, as mentioned above these falls seem to have become more frequent because the beach is diminished in part now in the Burton Cliff area. A point of interest regarding beach material is that the bed rock is exposed at the foot of the beach at low tide, as shown by photographs. Thus there is not a sediment surplus here, and the impression of diminution of the beach persists.

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BURTON CLIFF AND ROCK FALLS

YEAR - 2012 July - Rock Fall with Fatal Accident - More Information

A distant view of part of the debris cone of the Burton Cliff rock fall of 24th July 2012, Burton Bradstock, Dorset

A view of the rock fall at Burton Cliff, seen on 3rd August 2012 from the cliff top to the northwest

A broad, extended view of the part of Burton Cliff, that fell with a fatal accident, on the 24th July, 2012, Burton Bradstock, Dorset, photograph by Martin Cox

Rock fall accident at Burton Cliff, rescue teams at the beach seen at about two hours after the fall, photograph by Martin Cox from a boat

Rock fall of Bridport Sand Formation and Inferior Oolite etc at Burton Cliff, Burton Bradstock, Dorset, 24th July 2012, with a fatal accident, photographed from a boat by Martin Cox

Details of the fatal rock fall at Burton Cliff, Dorset, photographed by Martin Cox from a boat on the 24th July 2012

The rock fall of 24th July 2012, seen from the beach at low tide, 3rd August 2012, Burton Cliff, Burton Bradstock, Dorset

An oblique view from the beach to the southeast of the 24th July 2012 fatal rock fall at Burton Bradstock, Dorset, with photograph taken on the 3rd August

A large oblique view from the low tide mark just to the west of the Burton Cliff rock fall of the 24th July 2012, as seen on 3rd August 2012

Details of the lower part of the rock fall of the 24th July 2012, Burton Cliff, Burton Bradstock, as seen on the 3rd August 2012

Blocks of Inferior Oolite, fractured in jigsaw-like manner at impact on Bridport Sand debris, Burton cliff, Burton Bradstock, Dorset, photo 3rd August 2012

An inverted block of the Bajocian Red Bed, with snuff boxes, in the rock fall at Burton Bradstock, Dorset, 2012

The fracture pattern of the Bridport Sand Formation debris, rock fall of the 24th July 2012, Burton Cliff, Burton Bradstock, Dorset, photo 3rd August 2012

Shown above is the part of Burton Cliff, Burton Bradstock, Dorset where a tragic accident occurred as a result of a rock fall. Such falls are common here and are marked by scars on the cliff even after most of the rock debris has been eroded away by the sea. In most cases the falls happen when no-one is present at the locality. On the 24th July three people were buried in an initial sand fall; two were rescued, but sadly the third Charlotte Blackman could not be rescued and a 400 tonne rock fall followed. The scar and debris of this can be seen in the photograph above. More details are given further below.

The cliffs of Burton Bradstock fall from time to time, probably more frequently now, and the beach is becoming narrower. This is seen from time to time during field trips to the coast here. The fatal accident at Burton Cliff on the 24th July 2012 was not at the eastern end near Hive Beach, where there have been several falls recently, but in the middle to western part (about 400m east of the Burton Freshwater mouth of the stream, and near the eastern fence on the clift top and near a small promontory; actually just to the west of it;). The map reference is SY 482892) Some more information on this is given below. When on the beach it is only within short walking distance of the stream outlet (and thus the area of the holiday camp). You can see the place from the are of the stream mouth. It is quite a long way from Hive Beach, the main public car park on the coast at Burton Bradstock. It is not visible from Hive Beach.

To understand the risks of this stretch of cliff one should consider previous rock falls here. There is a long history of debri, mainly from the Bridport Sands and Inferior Oolite, descending suddenly to this beach. The falls seem to be happening more frequently now. Even in this same year, in early 2012, Alan Holiday (to whom I am much obliged), photographed a new rock fall near the Hive Beach end of Burton Cliff. This took place on the 12th February 2012. Clearly Burton Cliff is a cliff line always with a rock-fall risk.

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BURTON CLIFF AND ROCK FALLS

YEAR 2012 - BGS Landslide Response Team

The BGS (British Geological Survey) Landslide Response Team investigated the rock fall on the 25th July, the day following the fatal accident. See:
Burton Bradstock Rock Fall, Dorset.

. Re: The Burton Bradstock rock fall of 24 July 2012.
The BGS Landslide Response Team carried out a survey of the site, including a LiDAR survey, on 25 July 2012. Data collected from this survey is logged in the BGS National Landslide Database NLD 18684/1.
"It was reported that approximately 400 tons of rock fell in two rock-fall events approximately 20 minutes apart at around 12:30.. .The rock fall deposit was 30 m long, 20 m wide and 10 m high, which ran out over a gravel [actually fine shingle] beach."
The failure was controlled and constrained by a combination of factors:
Discontinuities: Joints and fractures within cliff run vertically and parallel to the cliff face enabling wedge-shaped sections of cliff to fall.
Coastal erosion and weathering: Coastal erosion and weathering of the cliff face are a continual natural process... The sea is eroding the base of the cliff (undercutting), removing support for the rocks above... The processes of weathering weakens the cliff, making it more susceptible to failure. Recent wet weather has added more water into the cliff from above such that grain support is weakened in the Bridport Sand Formation ... thereby increasing the likelihood of a landslide occurring."

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BURTON CLIFF AND ROCK FALLS continued:

YEAR 2012 continued

Possible Causitive Factors - Clay Mineral Expansion and Contraction.

The clay mineralogy of the Bridport Sands differs from that of some other local Jurassic Formations and has some interesting features, including perhaps some capabilities of expansion and contraction.

The clay minerals of the Bridport Sand Formation comprise mainly kaolinite and mixed layer clays of both the illite-chlorite and illite-smectite type ( Morris and Shepperd, 1981). In particular the adsorption of water can cause expansion of poorly crystalline mixed layer illite-smectites causing blockage of pore space. This can be a problem in the subsurface Bridport Sand Formation of the Wytch Farm Oil Field. It is interesting that this reduction is largely reversible on drying out. A possible matter of bulk expansion at the surface in wet weather conditions resulting from clay mineral expansion has not been researched. If the illite-smectite expansion is reversible then, at least in theory, some small contraction might occur during drying out of the Bridport Sand Formation in Burton Cliff.

This has not been investigated and thus, at the moment, is purely speculative. However, it might warrant further study.

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BURTON CLIFF AND ROCK FALLS -

YEAR - 2012 - ROCK FALL ACCIDENT - CORONER'S INQUEST

Coroner's Report - December 2012 - On the Rock Fall with Fatal Accident

Cliff landslip death: Charlotte Blackman '10ft from safety'

There was an Inquest in December 2012. The main points of the inquest were reported in the press.

[BBC News - online - 18th December 2012.]
The coroner at the inquest said no-one could have predicted what would happen. The boyfriend of a woman crushed to death in a beach landslide has said she was only 10ft (3m) away from him when the rocks came down. Charlotte Blackman, 22, of Heanor, Derbyshire, died after a 160ft (50m) high cliff near Burton Bradstock collapsed in July 2012.
Matthew Carnell told a Dorset inquest how it had all "happened so fast, within the blink of an eye". The coroner recorded an accidental death from an "act of nature." He said no-one could have predicted what would happen. .. continues

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More details of the Inquest were given in the "Bridport News". An article is available online at:

Death of Graduate in Burton Bradstock Landslide a Tragic Accident.

"A young woman was just seven feet from safety when she was killed instantly by a massive landslide near Burton Bradstock, an inquest was told. Holidaymaker Charlotte Blackman was strolling along Freshwater Beach with her family when 400 tonnes of rock crashed down on top of her. An inquest into her death at Dorchester was told that the rockfall was a 'sudden act of nature' which no-one could have predicted. Charlotte, 22, of Heanor in Derbyshire, died on July 24 despite a major rescue operation which lasted into the night.
She was staying ... at Freshwater Holiday Park when the tragedy happened. The university graduate was just 7ft feet away from her dad Kevin and 10 feet from boyfriend Matthew Carnell when the landslide happened. Mr Blackman said: "I was about seven feet from Charlotte when it happened. I heard a noise, looked up and saw a bit of dust come out a crack. I shouted run, turned around and she was gone. Several witnesses told the inquest they saw smaller cliff falls before the fatal landslide but Mr Blackman said they did not see any. Fisherman Leonard Muggeridge said he thought he heard 'gun fire' as one section of the lower cliff plummeted, leaving a significant overhang.
Witness David Warren said he shouted a warning to the group not to go down the beach where he had seen a landfall but her family say they did not hear him.... A post-mortem report stated that Miss Blackman’s death was caused by non-survivable injuries and would have been instantaneous.
Coroner Sheriff Payne said: "Sadly, Charlotte Blackman died as a result of an accident. It was a sudden act of nature that nobody could have predicted at that time."
---- [article continues]

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BURTON CLIFF AND ROCK FALLS continued:

YEAR 2012 and Future Prospects - More Rock Falls

An undercut and overhanging cliff near Burton Hive Beach,Burton Bradstock, Dorset, a site of a future rock fall

There is no reason to believe that the rate of rock fall at Burton Cliff is likely to decrease. In fact, it is bound to continue because erosion at the foot of the cliff is continuing and there no sign of an increase in protective beach material. If the rate of sea-level rise increases then an increase in rock falls at Burton Cliff is to be expected. There are many complicating factors. One of these is that the clay cliffs (Frome Clay) southeast of Burton Cliff are obviously retreating fairly fast. The clay is easily eroded. A building at Burton Hive beach has rock armour protection around it on the seaward side. It indicates quite rapid retreat. The result of this erosion and landward movement of the beach where there are clay cliffs means that the beach is now "out of step" with the beach at Burton Cliff. That is to say it is almost landward of the Burton Cliff beach. At the connecting area between the two there is much undercutting and rock falls are common. Severe undercutting at a threatening cliff site near Hive Beach is shown above. There will be a rock fall here in the not-too-distant future.

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BURTON CLIFF AND ROCK FALLS continued:

YEAR - 2012 - July Accident - Weather Conditions -Flooding

With regard to the July 2012 rock fall and accident, a previous abnormality in weather conditions must be noted. There had been a long period of abnormally heavy rainfall. At Burton Bradstock there had been major flooding. This is shown by the following reference to a webpage by Graham Wiffen:

Rain Stop Play : Burton Bradstock gets Top Spot: 07th July 2012.

Extract from text about flooding by River Bride (but go to webpage and see the impressive photographs):

"The return journey was a little easier, if longer, due to the number of accidents and road closures now in place. Our small team finally got back to Burton only to be greeted by a flooded village centre, the local garage forecourt under water, cars abandoned in amongst the flood waters and people being air lifted by helicopter.
Many of the local residents were told they were possibly to be evacuated and specialists were brought in to check the small road bridge, which was being put under enormous pressures by the weight of water running up against it, under it, and sometimes over it."

Possible effects of flood water of the River Bride percolating into the Bridport Sands on the 7th July 2012, Burton Bradstock, Dorset

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BURTON CLIFF AND ROCK FALLS

YEAR 2012

- July - Clay Downwash by Exceptional Rainfall

Wash down of clay from the Fullers Earth, Burton Cliff, Burton Bradstock, Dorset, 3rd August 2012

An area of clay downwashed from the Fullers Earth, western part of Burton Cliff, Burton Bradstock, Dorset, 3rd August 2012

The exceptionally heavy and prolonged rain of early July had some unusual effects on Burton Cliff. There seems to have been a major downwash of grey clay from the Fullers Earth which crops out in the central to western part of the cliff top area. The Fullers Earth is, at least in other areas, an expandible clay (smectite), hence the name (re the fulling or degreasing of wool). Large parts of the cliff have received a grey coating. This is absent, of course, in the scar of the fatal rock fall of the 24th July 2012. Where the Fullers Earth crops out rainwater does not percolate directly into porous and permeable rocks and run-off is therefore greater. Thus the water flow from the runoff of the heavy rain was probably greater in the region of the accident site than in some other parts of Burton Cliff, as, for example, near Hive Beach.

It was noted that even on the 3rd August 2012 there was much suspended grey clay in the seawater. This was in a belt adjacent to the shore.

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BURTON CLIFF AND ROCK FALLS

Year 2013 - January (continuing wet weather)

A major rock fall of 2013, near the fatal 2012 rock fall, Burton Cliff Burton Bradstock, Dorset, as seen obliquely from Burton Freshwater, 22nd May 2013

A rock fall at Burton Cliff in January 2013, Burton Bradstock, Jurassic Coast, Dorset

Continuing abnormally wet weather may be responsible for yet another Bridport Sand Formation rock fall at Burton Cliff in January, 2013. A link with wet weather is likely, but there is no suggestion that this was connected with any heat or drying of the cliff. It has the usual profile, although the photograph does not seem to show Inferior Oolite blocks.

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BURTON CLIFF AND ROCK FALLS

Year 2014 - January (stormy and exceptionally wet weather)

A view from East Cliff of distant Cliff, Burton Bradstock, with two new and large rock-falls, 9th January 2014, Alan Holiday photograph

The end of the Chesil Beach is now at unstable cliffs, Hive Beach, Burton Bradstock, Dorset, 9th January 2013, Alan Holiday photograph

Dangerously overhanging cliffs, that have been undercut by the sea, eastern Burton Cliff, Burton Bradstock, Dorset, 9th January 2014, photograph by Alan Holiday

.

The photographs above show the western end of the Chesil Beach at Burton Bradstock, where it has (in early January, 2014) lost much fine shingle. At high tide, at least, the end of the Chesil Beach is now at Burton Hive Beach. It does not continue as the Chesil Beach in front of Burton Cliff. Much beach sediment has been lost from there. Undercutting is taking place at the eastern end and rock-falls are occurring further west. There is a well-defined shortening in length of the Chesil Beach. Not long after the above photographs were taken, on about the 17th January 2014, there was a major rock fall in the area.

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Two rock falls, one of them very broad at Burton Cliff, Burton Bradstock, Dorset, as photographed by Alan Holiday on 19th January 2014

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A view of the broad Bridport Sand rock-fall towards the eastern end of Burton Cliff, Burton Bradstock, Dorset, 19th January 2014, photographed by Alan Holiday

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A short time after the major storm of 6-7th January 2014 the consequences of undercutting by the sea took place. There were substantial rocks falls. Two of these, kindly photographed by Alan Holiday are shown above. One of these is very broad and is almost entirely in Bridport Sand Formation. The further one has a debris cone which seems to contain large blocks of Inferior Oolite. Alan Holiday reported that good ammonite remains with gas chambers were found in the debris.

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BURTON CLIFF AND ROCK FALLS

PROCESSES

Rock Falls - Relation to Undercutting and Joints

A gull at a projecting section of Bridport Sand Formation, Burton Cliff, a piece which may fall later

A vertical joint, oblique to the cliff, and near the southeastern boundary of the July 2012 rock fall at Burton Cliff, Burton Bradstock, Dorset

Examination of the foot of the cliff shows quite clearly that undercutting is commonly present in the areas of rock falls. The fine shingle is very abrasive when activated by waves and cuts out a hollow under the cliff of Bridport Sand Formation. This is clearly a major cause of instability.

An additional factor, but probably not often the main cause, is the presence of joints in the Bridport Sand Formation in both Burton Cliff, Burton Bradstock and in East Cliff, West Bay. Certain of these are different from the various minor joints. They are large "gulls" or open fissures, often containing loose debris. They are most well-known from the Northampton Sand Ironstone Formation and associated with camber, or outward movement of a thick and resistant sandstone bed that is jointed. A gull is present at the southeastern side of the fatal rock fall at Burton Cliff. Some further opening of the gull might be a factor in relation to the cliff fall. However, it is very unlikely that all falls are at the location of gulls. The gulls are usually at a steep angle of about 45 degrees to the cliff front. They are not cliff-parallel or at the back of rock falls, and undercutting seems to be a more important factor.

A diagram illustrating the mode of rock fall from the Bridport Sands at Burton Cliff, Burton Bradstock, Dorset, resulting from undercutting by marine erosion

An opening joint at the southeastern side of the July 2012 rock fall at Burton Cliff, Burton Bradstock, Dorset

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BURTON CLIFF AND ROCK FALLS

PROCESSES

Loss of Beach Material at Burton Cliff

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BEACH MATERIAL

Progressive Loss at Burton Cliff.

The beach, however, has shown dramatic changes, becoming much narrower that in the past. This has been investigated by (Calloway, 2009). It is particularly narrow now at the eastern end near Hive Beach. This is also shown in some photographs above and the erosion of the cliffs seems to have increased to some extent here. The loss of beach is more significant.

There is a significant contrast at present between Burton Cliff of Bridport Sands and East Cliff, Bridport, also of Bridport Sands. East Cliff, although with a higher Bridport Sands section does not seem to show as many rock falls as does Burton Cliff.

Aerial view of the Chesil Beach thinning at Burton Bradstock East or Hive Beach, Dorset, 2012

The beach of Burton Cliff is relatively narrower now than in the past. It is fairly low and there is undercutting taking place at the foot of the cliff of Bridport Sands.

An old map of about 1811 shows that longshore drift towards Burton Cliff was from Bridport Harbour area, Dorset

Views of the northwestern part of the Chesil Beach from Burton Cliff, Dorset, in normal and storm conditions, 2008

Loss of beach material and exposure of fallen limestone at the western end of Burton Cliff, Dorset, in 2008, shown in comparison with an earlier photograph

Comparison of the southeastern end of Burton Cliff, Dorset, from 1996 to 2005

Erosion and loss of beach material at the southeastern end of Burton Cliff, near Burton Hive, Burton Bradstock, Dorset, from 1996-2008

Loss of beach material has resulted in wave action cutting an  overhang or cantilever at the base of the cliff of Bridport Sands at Burton Bradstock, Dorset, as seen 31st October 2009

The beach at Burton Bradstock, near the western end (the exact end is debatable) of the Chesil Beach, is fine shingle. It mostly consists of Cretaceous flint and chert (from the Upper Greensand) with a variety of unusual pebbles, including quartzites from the Budleigh Salterton pebbles beds of the Triassic of Devon. The small pebbles are generally fairly well-rounded. Notice that although most of the material is well-sorted, there are some larger pebbles scattered on the surface.

When the beach was observed in April 2005 it seemed to have diminished in width. By March 2008, as shown by the comparative photographs above, there had been substantial loss of beach material at Burton Cliff. The fine shingle (granules) move from west to east by longshore drift as a result of prevailing southwesterly winds. Supply of beach sediment from the west is prevented by the harbour piers (now extended) at West Bay, Bridport. Shingle is moved and banked up by machines at Burton Freshwater to reduce the risk of flooding of the caravan site there. Sea level is rising at an increased rate and in general the low water mark is moving landward along the coast of central southern England (beach narrowing, beach steepening or coastal squeeze). Thus, for various reasons, there is no longer the abundance of fine shingle that there used to be in front of Burton Cliff.

An old topographic map showing part of Burton Cliff,   The Hive and Burton Beach at Burton Bradstock, Dorset, in 1901

Possible erosional problems regarding the western end of the Chesil Beach at Bridport and Burton Bradstock, Dorset, as shown on a geological map

In the longer term the beach at Burton Cliff will probably be lost and this will become a rocky coast with the sea breaking onto the Bridport Sands. Fortunately, fallen blocks of limestone from the Inferior Oolite may provide some natural rock armour (armourstone) that may retard the rate of cliff erosion. It may become a headland, resistant in contrast to the relatively rapid retreat of the Fullers Earth clay cliffs to the southeast (from Burton Hive Beach towards Cogden Beach). The soft cliffs will erode easily once the main part of the shingle beach is lost and the area becomes sediment-starved (cf. Naish Farm at Highcliffe, Christchurch Bay).

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BURTON FRESHWATER

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. BURTON FRESHWATER

Sea Defences at Burton Freshwater

An artificially banked-up barrier of beach shingle to prevent flooding at Burton Freshwater, west of Burton Bradstock, Dorset, 3rd March 2008

A general view of Burton Freshwater from the northwestern end of Burton Cliff, Burton Bradstock, Dorset, on 3rd August 2012

A view of East Cliff, West Bay, seen across the Burton Freshwater gap from Burton Cliff, Burton Bradstock, Dorset, 3rd August 2012

Burton Freshwater, northwestern side, at the beginning of East Cliff, showing some rock fall hazard, Burton Bradstock, Dorset, 3rd August 2012

Deflected outflow of the River Bride at Burton Freshwater near Burton Bradstock, Dorset, 3rd March 2008

Rapid erosion of a low cliff near the outflow of the River Bride, Burton Bradstock, Dorset, 3rd August 2012

The low flood plain of the River Bride comes down to the sea at Burton Freshwater to the west of Burton Bradstock. Here there has been flooding in the past. If there were no defences here major sea-flooding could extend up the valley into the village of Burton Bradstock. Obviously the mouth of the river has to be left open. However, immediately, to the west of it shingle is banked up by a bulldozer to afford some protection the caravan park there and the flood plain in general. Unfortunately though the supply of fine shingle in the area is diminishing as the beaches here progressively become narrower. Rising sea-level is moving the low-water mark landward. Rising high water level, particularly when raised further by storm surges, is a potential threat to river floodplains which reach the coast.

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BURTON FRESHWATER

Jointing in the Bridport Sand Formation

Widened joints in calcite-cemented beds at Burton Freshwater, Burton Bradstock, Dorset, 3rd August 2012

Joints in the calcite-cemented beds of the Bridport Sand Formation at the mouth of the River Bride are apparently widened and very conspicuous. This may be the effect of periglacial activity in the Devensian, simply because this would have been near-surface at that time, and periglacial fracturing is very common at other localities. However, the joints may in fact be hidden tectonic joints, present throughout the Bridport Sand Formation, but not open and therefore not generally visible. This may require further study.

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ACKNOWLEDGEMENTS

Martin Cox very kindly has allowed me to use some of his photographs taken from the sea after the July 2012 rock fall at Burton Cliff. I am much obliged to him. I would like to thank Gareth Lloyd for the opportunity to scan and use photographs taken by him of the Burton Cliff section. I am obliged to David Sole for informing me about the 2005 cliff-fall. Thanks are due to the staff and students of London South Bank University who helped with field work at Burton Bradstock. I am very much obliged to Adrian Bicker for kindly providing storm and other photographs taken from Burton Cliff. As elsewhere on this website Alan Holiday has very kindly provided some many excellent photographs of overhanging cliffs and of various rock-falls on this stretch of coast. In particular he photographed the rock fall at Burton Bradstock in February 2012 and I am very grateful for his permission to use these photographs.

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REFERENCES AND BIBLIOGRAPHY

(See also References in the East Cliff, West Bay, Bridport webpage.)


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Allison, R.J. 1992. The Coastal Landforms of West Dorset. Geologists' Association Guide No. 47. 133 pp. Edited by Robert J. Allison, Department of Geological Sciences, University College, London.

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Arkell , W.J. 1933. The Jurassic System in Great Britain. Clarendon Press, Oxford, 681pp.

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Barnard , T. and Hay, W.W. 1974. On Jurassic coccoliths: a tentative zonation of the Jurassic of S. England and N. France. Eclogae Geol. Helv., 67, 563-585.
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Barrett , C. 1878. The Geology of Swyre, Puncknowle, Burton Bradstock, Loders, Shipton Gorge, Litton Cheney, Longbredy, Littlebredy and Abbotsbury, Dorset. Bridport.
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Barron , A.J.M., Sumbler, M.G. and Morigi, A.N. 1997. A revised lithostratigraphy for the Inferior Oolite Group (Middle Jurassic) of the Cotswolds, England. Proceedings of the Geologists' Association, London. 108: 269-285. Abstract: Geological surveying in part of the Cotswolds has provided a basis for a modem lithostratigraphical classification of the Inferior Oolite Group. The group is divided into three formations, named the Birdlip Limestone Formation, Aston Limestone Formation and Salperton Limestone Formation, in ascending order. These correspond essentially with the traditional units of Lower, Middle and Upper Inferior Oolite which were defined chronostratigraphically. Each of the three formations is subdivided into members which can be related to units well established in the existing literature. Formal definitions of all these units are given. (Not on Burton Bradstock, but relevant for comparison and key to literature).
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Bird, E.C.F. 1990 (for 1989). The beaches of Lyme Bay. Proceedings of the Dorset Natural History and Archaeological Society for 1989, published June 1990, 111, 91-97. By the late Eric Bird, then at Department of Geography, University of Melbourne, Australia. Abstract: The beaches of Lyme Bay consist largely of flint and chert shingle, with some sand, derived from eroding cliffs and sea floor sources. They include Chesil Beach, which shows lateral grading from small pebbles in the west to large pebbles in the east. Several other beaches on the north coast of Lyme Bay also show lateral grading, low beaches of poorly sorted sand and shingle to the west becoming higher and often wider, coarser and better sorted to the east. Lateral grading is attributed to an alternation of eastward beach drifting by strong south-westerly wave action with westward movement of finer material by gentler southeasterly wave action. Whereas Chesil Beach is a relict shingle formation, the other beaches are still receiving small quantities of sand and shingle. Cliff erosion and slumping are more rapid behind low beach sectors than where a high, wide accumulation of coarse shingle protects the shore. It is suggested that artificial beach nourishment should be used as a method of coastal protection on the shores of Lyme Bay. [end of abstract - Bird, 1990]


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Bray , M.J. 1986. A Geomorphological Investigation of the South West Dorset coast. Volume 1: Patterns of Sediment Supply. Report to Dorset County Council, 144pp.

Bray, M.J. 1986. A Geomorphological Investigation of the South West Dorset coast. Volume 1: Patterns of Sediment Transport. Report to Dorset County Council, 798pp.

Bray, M.J. 1992. Coastal sediment supply and transport [re West Dorset]. In: Allison, R.J. (Ed.) 1992. The Coastal Landforms of West Dorset. The Geologists' Association, 134 pp., paperback, pp. 94-105.
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British Geological Survey (BGS). (Compiler Wood, M.A.) 2011. Geology of South Dorset and South-East Devon and its World Heritage Coast.
Special Memoir for 1:50,000 geological sheets 328 Dorchester, 342 West Fleet and Weymouth and 342/343 Swanage and parts of sheets 326/340 Sidmouth, 327 Bridport, 329 Bournemouth and 330 Newton Abbott. Compiled by M.A. Woods. By Barton, C.M., Woods, M.A., Bristow, C.R., Newell, A.J., Westhead, R.K., Evans, D.J., Kirby G.A., and Warrington, G. Contributors: Biostratigraphy - J.B. Riding; Stratigraphy - E.C. Freshney; Economic Geology - D.E. Highley and G.K. Lott; Engineering Geology - A. Forster and A. Gibson. British Geological Survey, Keyworth, Nottingham, 2011. 161 pp. This is the new version of the Geological Survey Memoir for the Dorset Coast etc. and replaces Arkell (1947) and the earlier memoir by Strahan (1898). It covers a wider area than these old memoirs, though, and includes all of "Jurassic Coast", UNESCO World Heritage Coast. It is a key reference work. Available from BGS Online Bookshop at 24 pounds stirling (in Jan. 2012).
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BGS. British Geological Survey. BGS Landslide Response Team. Report.
The BGS (British Geological Survey) Landslide Response Team investigated the rock fall on the 25th July, the day following the fatal accident. See: Burton Bradstock Rock Fall, Dorset. Re: The Burton Bradstock rock fall of 24 July 2012. The BGS Landslide Response Team carried out a survey of the site, including a LiDAR survey, on 25 July 2012. Data collected from this survey is logged in the BGS National Landslide Database NLD 18684/1.
"It was reported that approximately 400 tons of rock fell in two rock-fall events approximately 20 minutes apart at around 12:30.. .The rock fall deposit was 30 m long, 20 m wide and 10 m high, which ran out over a gravel beach... The failure was controlled and constrained by a combination of factors: Discontinuities: Joints and fractures within cliff run vertically and parallel to the cliff face enabling wedge-shaped sections of cliff to fall. Coastal erosion and weathering: Coastal erosion and weathering of the cliff face are a continual natural process... The sea is eroding the base of the cliff (undercutting), removing support for the rocks above... The processes of weathering weakens the cliff, making it more susceptible to failure. Recent wet weather has added more water into the cliff from above such that grain support is weakened in the Bridport Sand Formation ... thereby increasing the likelihood of a landslide occurring."
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Bryant , I. A., Kantorowicz, J. D. and Love, C.F. 1988. The origin and recognition of laterally continuous carbonate-cemented horizons in the Upper Lias Sands of southern England. Marine and Petroleum Geology, 5, 108-133. (cementation of bioclast-rich storm sediments on submerged marine shoal. Compared with Mauritanian shelf).
The Upper Lias Sands of southern England contain numerous, laterally extensive, carbonate-cemented horizons. Petrographic analysis of samples from outcrop sections and Marchwood No.1 borehole indicate that these horizons result from preferential cementation of bioclast-rich, clay-poor sediments by comparison with interbedded clay-rich, bioclast poor sediments. The alternation of the two sediment types is attributed to the effects of, respectively, fairweather and storm processes on a submerged marine shoal. Petrographical and ichnological data indicate an early distinction of the strongly and weakly cemented horizons. The widespread extent of the cemented horizons, as indicated by outcrop studies on the Dorset coast, is considered to be a direct consequence of episodic storm activity on the low relief shoal. Sedimentological, palynological and petrophysical criteria are presented to assist in recognition of similar extensive cements in subsurface reservoir horizons.

Bryant, I. A. and Kantorowicz, J. D. (listed as in prep.). Upper Lias Sands of the Marchwood No. 1 Borehole, southern England, In: The Reservoir Geology of the North Sea, B.S.R.G. core workshop. (Eds J. Melvin and G.M. Walkden).
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Buckman , S.S. 1881. A descriptive catalogue of some of the species of ammonites from the Inferior Oolite of Dorset. Quarterly Journal of the Geological Society, London, 37, 588-608.

Buckman, S.S. 1883. The brachiopoda from the Inferior Oolite of Dorset and a portion of Somerset. Proceedings of Dorset Natural History and Archaeological Field Club, 4, 1-52.

Buckman, S.S. 1891. The ammonite zones of Dorset and Somerset. Geological Magazine, 28, 502-504.

Buckman, S.S. 1910a Certain Jurassic (Lias-Oolite) strata of South Dorset. Quarterly Journal of the Geological Society of London, 66, 52-89..

Buckman, S.S. 1910b. Certain Jurassic (Inferior Oolite) species of ammonites and brachiopoda. Quarterly Journal of the Geological Society of London, 66, 90-108, 109-110.

Buckman, S.S. 1913-1919. Yorkshire Type Ammonites, 2. London.

Buckman, S.S. 1922-3. Type Ammonites, 4. London

Buckman, S.S. and Secretary. 1908. Illustrations of type specimens of Inferior Oolite ammonites in the Sowerby Collection. Monographs of the Palaeontographical Society of London.

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Coggan, J.S., Pine, R.J. and Stead, D. 2001. A proposed methodology for rockfall risk assessment along coastlines. Geoscience in south-west England, vol. 10, pp. 190-194.
Available online:
A Proposed Methodology for Rockfall Risk Assessment along Coastlines.
Many of the general public use the coastal zone for recreation during the summer. They often spend time in the vicinity of of cliff exposures that may constitute a risk from instabilities. Rockfall hazard appraisal and risk assessment techniques were applied to a length of Cornish coast, predominantly in sandstones and mudstones between Hayle and Portreath, to assess the threat to the public on the adjacent beaches. The methodology used was similar to assessments of rockfall on highways. Even though risk assessments are voluntary, the general public should be informed of the risks of rockfall. The results of this analysis suggest that for the occasional beach user, the risk may be small, when compared to the risk from other voluntary activities such as rock climbing. Increased exposure and the nature of the recreational pursuit may increase risk. [end of abstract]
Introduction:
The detrimental effects of coastal landslide activity have received extensive coverage in the national press in recent months, following one of the wettest winters for more than 100 years. Many of the public visit the coastal zone for recreation. Where beaches are backed by cliffs, the public often spend time in areas that constitute a risk from instabilities. With the predicted increase in wet-winters and storm-related damage as a result of climate change, then increased rates of coastal recession are forecast. Coastal cliff instability must, therefore, be a consideration for users of coastal zone for business, tourism and recreational purposes. Instability can directly affect both coastal paths and beaches. The potential for instability may therefore have a detrimental impact on small business, local maritime authorities, private landowners, highway authorities and the general public. This is important for Cornwall as over 20% of the gross domestic product is generated by tourism (Shail et al., 1998) and the coastline is over 200 miles long.
Assessment of landslide activity, and the instability of the Cornish coastline, has been carried out under the Shoreline Management Plans (SMP), using qualitative evaluation. The data incorporated in the SMP was based on a review of available literature, air photograph surviellance and field visits. The risk or likelyhood of injury to persons from rockfall when using beaches backed by cliffs for recreation has not been quantified. [continues].
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Callomon , J.H. 1995a. 'Time from fossils: S.S. Buckman and Jurassic high resolution geochronology'. In Le Bas, M.J. (ed.) Milestones in Geology. Geological Society, London, Memoirs, 16, 127-150.

Callomon, J.H. 1995b. The Jurassic Geology of Dorset, Middle Jurassic. In. Taylor, P.D. (ed.), Field Geology of the British Jurassic. Geological Society, London, 60-85.

Callomon, J.H. and Chandler, R.B. 1990. A review of the ammonite horizons of the Aalenian-Lower Bajocian stages in the Middle Jurassic of Southern England. In: Cresta, S. and Pavia, G. (eds.), Atti del meeting sulla stratigrafia del baiociano. Memorie descrittive della carta geologica d'Italia. 40, 85-111.
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Calloway, T. 2009. The Use of GIS and Historic Maps to Investigate Temporal and Spatial Shoreline Variation at Burton Bradstock and West Bay, Dorset. 115 pp. Dissertation submitted in partial fulfilment of for the degree of B.Sc. Environmental Science; School of Civil Engineering and the Environment, University of Southampton. April 2009. By Thomas Callaway, April 2009. (supervised by Ian West)
Burton Bradstock and West Bay are situated on the Dorset coast, UK. The cliff sections are under threat from sea-level rise and increased storm frequency and intensity. Erosion rates may vary across different sections, due to famed geodiversity of the 'Jurassic Coast'. Anthropogenic developments and activities could also have an adverse effect on erosion rates. Different stakeholders have different opinions on how coast should be managed here. The World Heritage Site designation prevents further development because erosion is the key factor which makes the coast what it is. Residents and businesses may be concerned that land and buildings are being allowed to fall into the sea. Learning more about the causes and rates of erosion can help to understand predicted rates of change set out by Shoreline Management Plans (SMPs).
Historic Ordnance Survey maps have been used in digital format with ArcMap GIS software to determine differences in the coastline between published years. Rates of cliff-top recession and changes in the beach size and tidal range have been calculated at four cliff sections. The data has been used to investigate temporal and spatial variations in coastal processes, combined with knowledge of historical developments on the coast. The interaction between temporal and spatial factors has also been considered.
The results suggest that there are significant differences between the four cliff sections, due to their geology and structure and also because the development of harbour piers at West Bay over past centuries. Extensive beach mining has also played a part in affecting coastal processes. Significant interactions between spatial and temporal factors suggest that there are many more factors that have not been considered, prompting further research into various coast-related processes and phenomena. [end of Abstract].
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Cope , J.C.W. et al. A Correlation of Jurassic Rocks in the British Isles. 2. Middle and Upper Jurassic. Geological Society of London, Special Reports, 15, 3-21.

Cope, J.C.W. 2012. Geology of the Dorset Coast. Geologists' Association Guide, No. 22. 232pp., with many colour photographs and diagrams. New edition by John C.W. Cope. (See also the earlier editions by House, M.R. 1989 and 1993.)

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Davies , D.K. 1966. The Sedimentary Petrology of the Upper Lias Sands and Associated Deposits in Southern England. Unpublished Ph.D. Thesis, University of Wales. Supervised by Gilbert Kelling, University College of Swansea.

Davies, D.K. 1967. Origin of friable sandstone-calcareous sandstone rhythms in the Upper Lias of England. Journal of Sedimentary Petrology, 37, 1179-1188. By David K. Davies, then at Department of Geology, Texas A&M University, College Station, Texas. Later at: Geosystems, David K Davies And Associates Inc., 1410 Stonehollow Drive, Humble, TX 77339-2070. This paper represents a portion ot the Ph.D. thesis of D.K. Davies (1966), referred to above.
The diachronous Upper Lias Sands of southern England are comprised of small scale rhythmic alternations of friable, yellow sandstone and firm grey calcareous sandstone. In general, the alternating layers are parallel to bedding and to one another; exceptions occur where the calcareous sandstones mark out the bases of erosional structures. Individual carbonate-rich or deficient horizons cannot be correlated between outcrops 2 - 3 miles [3 - 5km] apart, but within a single outcrop they preserve a remarkable uniformity in vertical sequence. Petrographic studies demonstrate that original textural relationships are retained in the calcareous sandstones, while the friable sandstone interbeds have undergone compaction effects. Field evidence indicates that the calcareous sandstones were lithified before the deposition of more than 6 inches [15cm] of superimposed sediment. Such lithification is estimated to have taken approximately 150 years [i.e. 10cm per 100 years].
The alternations are considered to be the result of fluctuating rates of detrital deposition: the calcareous sandstones representing temporally and spatially restricted locales characterised by little or no detrital deposition, and the sandstone interbeds representing contiguous area of more rapid detrital deposition.
Within the Upper Lias Sands a gradual increase is observed in the relative proportion of calcium carbonate to detritals. This process established conditions suitable for deposition of the succeeding limestone sequences [Inferior Oolite] - an environment foreshadowed by the calcareous sandstones of the Upper Lias Sands.

Introduction:
General Statement.
The Upper Lias Sands of southern England are characterised throughout their outcrop by regular sedimentary layers alternately rich and deficient in calcium carbonate (fig.1). This, the most striking feature of the Sands at outcrop, has received scant attention despite the many geologists who have worked in the Upper Lias (Boswell, 1924; Buckman, 1875; 1879; Buckman, 1889; and Richardson, 1910, 1915, 1928-30). The purpose of this paper is to describe and explain this characteristic rhythmic alternation of friable sandstones and calcareous sandstones, highly unusual alternation in sediments of this lithology, and to interpret its significance in terms of regional sedimentology.
Regional Stratigraphy.
Sediments involved in this discussion crop out along a north-south line from the vicinity of Cheltenham to the south coast of southern England (fig. 2). The Upper Lias Sands represent a diachronous formation (average thickness, 200 feet [61m] which is almost entirely restricted to the Toarcian Stage of the Lower Jurassic. In the north the Sands are well represented in the Lower Toarcian subzone of Zugodactylites braunianus, but become progressively younger in a southerly direction unit, at the southernmost extremity of outcrop, they characterise in part the uppermost Toarcian subzone of Pleydellia aalenensis and also the basal Bajocian subzone of Leioceras opalinum (fig.3). This progressive change in stratigraphic position is representative of southerly facies migration rather than a change in provenance (Boswell, 1924; Davies 1966). As a result, over the total outcrop this formation preserves a remarkable uniformity both in petrology and rhythmic layering.
With a mean grain size of 4.00 phi (0.60 mm), the Upper Lias Sands bridge the sand-silt boundary. ..... [continues]

Davies, D.K. 1969. Shelf sedimentation: an example from the Jurassic of Britain. Journal of Sedimentary Petrology, 39, 1344-1370, December, 1969. By David K. Davies, of the Department of Geology, Texas A & M University, College Station, Texas. Abstract: The refined biostratigraphic framework that has been developed for Jurassic sediment of northwest Europe enables precise environmental distinctions to he made on a time-equivalent basis. Using such control it can be demonstrated that shelf sedimentation in the Lower Jurassic (Toarcian) of southern England was dominated by the gradual migration of a large sand bar. Despite the general homogeneity of its detrital sandstones and siltstones, this bar may be subdivided into four principal environments of deposition which including 1) bar (beach and upper shoreface), 2) fore-bar (middle shoreface, 3) back bar, and 4) tidal channel. These environments are distinguished on the basis of qualitative and quantitative textural and compositional criteria; succession of sedimentary structures, bioturbation, grain size, sorting, skewness, and petrography. The bar complex is 150 ft thick, and is transitional downward and southward into condensed limestones and argillaceous siltstones (40 ft average thickness). The limestones are principally intramicrites, the intraclasts being of the same composition as the host sediment (biomicrite), and often display oxidation rims. Such deposits are considered to be of shallow, marine origin. On the other hand, the argillaceous siltstones, which may contain up to 20 percent micrite, represent deeper marine conditions of deposition. The bar complex is succeeded upward and to the north by condensed limestones of variable composition, principally oomicrite; pisomicrites, and biomicrites. These limestones (12 ft average thickness) represent a platform interior sand blanket which was developed under shallow marine conditions in the lee of the large bar complex. Because 1) new sediment was constantly added to the southward side of the bar, and 2) subsidence did not quite keep pace with sediment supply, the bar was forced to accrete continually in a southward direction, at a rate of 1 mile per 80,000 years. The gradual southward migration of the bar resulted in preservation of vertical sequences which, when completely developed, comprise a basal argillaceous and calcareous facies (the Upper Lias Clay Formation), succeeded by an arenaceous facies (the Upper Lias Sand Formation), and capped by a calcareous facies (the Cephalopod Bed Formation). Sediments comprising these three facies were deposited in two distinct basins of deposition, separated by an east-west trending structural high (the Mendip Axis). Both basins subsided to receive a maximum thickness of some 340 ft of marine sediments. Because of the southward migration of the bar, the southern basin received its major sediment input only after the northern basin had already been filled. The nature and rate of sediment supply remained constant throughout the 6 million years duration of the Toarcian, the principal source being a meta-igneous complex located in the present western approaches to the English Channel.


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Davies , G.M. 1956. The Dorset Coast: A Geological Guide. Adam and Charles Black, London, 2nd Edition with 14 photographs and 33 figures. 128pp. Hard cover. This is an interestng old field guide mainly of historic interest.

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Evans, R. 2009. Boy Buried in Rockfall [at Lulworth Cove]. Daily Mirror, short newspaper article by Rebecca Evans.
A boy of nine was seriously injured when he was crushed by a ton of rocks which tumbled from a seaside cliff yesterday as he played on a beach. He and a younger girl were on the sand when the boulders suddenly came crashing down, hitting them both. The boy was buried up to his neck and suffered bad injuries to his head, neck and spine.
He was airlifted to hospital where his condition was being assessed last night after the horrific accident at the picturesque Lulworth Cove in Dorset. The girl was less seriously hurt.
Two shocked bypassers dialed 999 after seeing the rocks smash into them. A coastguard spokesman said: "The lad was very lucky not to have been killed. "The first report we had was that rocks weighing at least a ton had buried him up to his neck. When the rocks fall from the cliff - and that is always a possibility around the Dorset coast because of the rock structure - they pick up speed as they tumble down.
The boy and girl from Romsey and Ringwood, Hants, were with their respective dad and mum, who were a couple on a day out to the cove. It is a popular tourist destination on the Jurassic Coast World Heritage Site.
There have been rockfalls there before and around 10 people are killed by similar incidents in Britain every year.
[On Sunday, July 7th 1957, there was a similar rock fall at Black Rocks, Lulworth Cove: "9 in Hospital after Cove Rock Fall". "Nine people hurt by rocks that fell 100 feet to a crowded beach at Lulworth Cove, Dorset, were still in hospital today. A spokesman at Dorchester County Hospital said that were "fairly comfortable". [- continues]. Of course, there will be another rock fall here sooner or later and the consequences could be worse. My comments - It is not that the cliff is much more dangerous than elsewhere; cliff commonly have rock falls. The problem here is that people sit on the beach here almost every day there is fine weather. Rock falls occur at many places; fatal rock falls occur where people go.]

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Gatrall , M., Jenkyns, H.C. and Parsons, C.F. 1972. Limonitic concretions from the European Jurassic with particular reference to the "snuff boxes" of southern England. Sedimentology, 18, 79-103.
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Gauthier , H, Rioult, M. and Trevisan, M. 1995. Exceptional biostratigraphical record in the Oolithe-Feruugineuse-de-Bayeux, south of Caen (Calvados) - standard section for future reference as complement of the Bajocian historical stratotype. Comptes Rendus de l Academie des Sciences, Serie ii, Fascicule a -Sciences de la Terre et des Planetes, 321: (4) 317-323. Abstract: New stratigraphical data based on centimetre by centimetre collecting of ammonites at Feuguerollessur-Orne South of Caen, has led to detailed biozonation of the ''Oolithe ferrugineuse de Bayeux'' from the base of the Humphriesianum Zone up to the Parkinsoni one. The presence of relatively thick (3 m) deposits provides data giving far more detailed zonation (16 horizons are recognizable) than the ferruginous oolite in the Bayeux area, very condensed and locally reworked (Rioult, 1964; Pavia, 1994). Complemented by study of the inferior Bajocian and of the Aalenian/Bajocian boundary present in the same quarry, this section stands out as a standard for future reference complementary to the historical stratotype at Sainte-Honorine-des-Pertes near Bayeux (d'Orbigny, 1849-1852). (In French, not on Burton Bradstock, but relevant for comparison.).
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Hesselbo , S. 1992. Excursion A1. Tectonics and Sedimentation in the Lower/Middle Jurassic of the Wessex Basin. Pp 20-30. BSRG 1992, Southampton, Field Excursion Guides. Department of Oceanography, University of Southampton, 65 p.
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House , M.R. 1993 (and earlier edition in 1989) - Geology of the Dorset Coast. Geologists Association Guide, No. 22. 2nd edition, 164 pages plus plates. ISBN 0 7073 0485 7. [This inexpensive, conveniently small, paper back guide should be carried in the field as a very useful source of information by all seriously studying the geology of the Lulworth area or other parts of Dorset. It is full of detailed information and is concise and accurate. It enables field leaders to obtain essential information quickly and without carrying much weight of publications.]

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Jones , L.E. and Sellwood, B.W. 1989. Paleogeographic significance of clay mineral distributions in the Inferior Oolite Group (Mid Jurassic) of southern England. Clay Minerals, 24 (1), 91-105.
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Lang , W.D. 1962. Aalenian, Bridport Sands. Proceedings of Dorset Natural History and Archaeological Society, 83, p. 34.
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Lee, E.M. 1992. Urban Landslides: Impacts and Management. By E. Mark Lee, pp. 80-93 in: Allison, R.J. 1992. The Coastal Landforms of West Dorset. Geologists' Association Guide No. 47. 133 pp. Edited by Robert J. Allison, Department of Geological Sciences, University College, London.

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Melville , R.V. and Freshney, E.C. 1982. British Regional Geology: The Hampshire Basin and Adjoining Areas. British Geological Survey (formerly the Institute of Geological Sciences), London, Her Majesty's Stationery Office. 146 pp.


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Morris, K.A. 1979. An Integrated Facies Analysis of Toarcian Organic-Rich Shales and Contiguous Deposits in Great Britain. Ph.D. Thesis, University of Reading.

Morris , K. A. and Shepperd, C.M. 1982. The role of clay minerals in influencing porosity and permeability characteristics in the Bridport Sands of Wytch Farm, Dorset. Clay Minerals, (The Mineralogical Society) 17, 41-54.
Abstract: The Bridport Sands is a widespread marine sandstone of Lower Jurassic age found in much of southern England. It is very fine fine grained, moderately sorted quartz-arenite and is characterised by alternations of friable and hard calcareous-cemented layers. The sands form the upper reservoir of the Wytch Farm Field, Dorset, which is currently producing at the rate of around 4000 barrels of oil per day. Investigation of core material to assess the suitability of water injection for gas/oil recovery has shown that significant reductions of liquid permeability compared to air permeability occur. These reductions vary from 30% or less in the best quality reservoir to more than 70% in low permeability sandstones. Clay minerals in the Bridport Sands comprise mainly kaolinite and mixed-layer clays of both the illite-chlorite and illite-smectite types. Small amounts of vermiculite and chlorite also occur. The kaolinite is found as loosely attached, discrete particles, whilst the mixed-layer clays form patchy pore linings. The permeability reductions may be explained by: (i) the adsorption of water and expansion of poorly crystalline mixed layer illite smectites causing blockage of pore space (this reduction is largely reversible) and (ii) the physical movement of authigenic kaolinite crystal aggregates blocking pore throats (this reduction is largely non-reversible). The pore size distribution, clay particle sizes, the distribution of the clays within the pore space, and the composition of the clays are all important factors in controlling porosity/permeability relationships and permeability reductions in the friable reservoir intervals of the Bridport Sands.
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Mortimore , R.N., Lawrence, J., Pope, D., Duperret, A. and Genter, A. 2004. Coastal cliff geohazard in weak rock: the UK Chalk cliffs of Sussex. Pp. 3-31 in: Mortimore R.N. and Duperret, A. 2004. Coastal Chalk Cliff Instability. Geological Society of London, Engineering Geology Special Publications, No. 20, 173 pp. ISBN 1-86239-150-5. [Not on Burton Bradstock but relevant to cliff falls there.]
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Natural History Museum , London. (originally as British Museum (Natural History) 1962 and various editions onward). British Mesozoic Fossils. 207pp.

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Palmer , T.J. and Wilson, M.A. 1990. Growth of ferruginous oncoliths in the Bajocian (Middle Jurassic) of Europe. Terra Nova, 2, 142-147.
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Parsons , C.F. 1970. A new temporary section in the Inferior Oolite of south Dorset. Proceedings of the Dorset Natural History and Archaeological Society, 93, 117-118.

Parsons, C.F. 1974. The sauzei and 'so-called' 'sowerbyi' Zones of the Lower Bajocian. Newsletters in Stratigraphy, 3, 153-180.

Parsons, C.F. 1975. The stratigraphy of the Stony Head cutting. Proceedings of the Dorset Natural History and Archaeological Society, 96, 8-13.

Parsons, C.F. 1980. Aalenian and Bajocian correlation chart. In: Cope, J.C.W. et al. A Correlation of Jurassic Rocks in the British Isles. 2. Middle and Upper Jurassic. Geological Society of London, Special Reports, 15, 3-21.

Parson, C.F. 1980. Ph.D. Thesis, - also other papers by Parsons - for bibliographic details see: Thomas, J. and Ensom, P. 1989. Bibliography and Index of Dorset Geology. Dorset Natural History and Archaeological Society. 102 pages. [This includes details of 11 publications by Parson, many relevant to the succession at Burton Bradstock.]
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Penn , I.E., Dingwall, R.G. and Knox, O'B. 1980. The Inferior Oolite (Bajocian) sequence from a borehole in Lyme Bay, Dorset. Institute of Geological Sciences, Natural Environment Research Council, London, HMSO. ISBN 0 11 884098 3, 27 pp. Summary: A borehole drilled in Lyme Bay cored 19.30 m of ammonite-bearing Inferior Oolite limestone and proved all the Bajocian zones from Ludwigia murchisonae to Parkinsonia parkinsoni. Bajocian dinocyst, sporomorph, coccolithophorid, foraminiferal and ostracod assemblages are related to the ammonite zones and subzones for the first time. When the palaeontological and petrographical descriptions are combined with previously published data a reconstruction of the depositional environment and the delineation of the South-Dorset High as one of the several 'swells' controlling Bajocian sedimentation in southern England can be made. (Chamosite present).
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Perkins , J.W. 1977. Geology Explained in Dorset. David and Charles, Newton Abbot, 224 pp.
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Radley , J.D. 1986. Notes on a Bajocian stromatolitic limestone from Burton Bradstock, Dorset. Proceedings of the Dorset Natural History and Archaeological Society, 107, 184-186.

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Richardson , L.R. 1915. Report of an excursion to Bridport, Beaminster and Crewkerne. Proceedings of the Geologists' Association, London, 26, 47-78. April 9th to 14th (Easter), 1914. By L.R. Richardson, F.R.S.E., F.G.S., Director of the Excursion.

April 9th. "The official party travelled from Paddington by the 10.30am train and arrived in Bridport at 1.55 pm. Here a number of members from other parts joined those from the town. Headquarters were in the Bull Hotel, Bridport. Mr. Douglas Leighton acted as Secretary of this excursion...."

[p.57. Burton Cliff] "During the walk along the beach to the place where the huge masses of oolite have fallen bodily down, the precipitous cliffs of Bridport Sands, capped with Oolite and Fullers' Earth, were much admired. The position of the Red Bed could easily be made out by its red stain.
Considerable discussion took place as to the origin of the layers of sand-rock and sandburrs; but no satisfactory explanation was forthcoming. The hard beds are highly calcareous and water exuding from their neighbourhood has frequently formed a lace-like travertinous deposit pendent from one hard stratum to another. In places percolating waters, charged with bicarbonate of lime, have originated in the softer intervening deposits a kind of box structure, some said very similar in appearance to that known in the Hastings Sands.
Arrived at the tumbled blocks the Members saw that masses had bodily fallen down, in which it was possible to identify the various beds from the Sands to the Fullers' Earth. Each bed could be conveniently measured and fossils collected. A vertical section of the Inferior Oolite and contiguous deposits to be seen here was given in our Circular and is reproduced (with some slight alteration) on p. 55. [this is the standard Inferior Oolite section for Burton Cliff, shown elsewhere in this webpage]. [continues .]

Richardson, L.R. 1928-30. The Inferior Oolite and contiguous deposits of the Burton Bradstock - Broadwindsor district, Dorset. Proceedings of the Cotteswold Naturalists' Field Club, 23, 35-68; 149-185; 253-264, pl. 2-6, 19-25, 28.

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Sellwood , B.W. and Jenkyns, H.C. 1975. Basins and swells and the evolution of an epeiric sea (Pliensbachian - Bajocian of Great Britain). Journal of the Geological Society of London, 131, 373-388.
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Senior , J.R. 1968. Ammonite finds of stratigraphical importance in the Inferior Oolite of Dorset. Proceedings of the Dorset Natural History and Archaeological Society, 89, p.45.

Senior, J.R., Parsons, C.F. and Torrens, H.S. 1970. New sections in the Inferior Oolite of south Dorset. Proceedings of the Dorset Natural History and Archaeological Society, 91, 114-119.
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Sylvester-Bradley , P.C. 1957. The Forest Marble of Dorset. Proceedings of the Geologists Association , 1556, 26-28.

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Thomas , J. and Ensom, P. 1989. Bibliography and Index of Dorset Geology. Dorset Natural History and Archaeological Society. 102 pages. See also the internet version - Bibliography and Index of Dorset Geology.

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UK Fossils Network. 2012.
Burton Bradstock Fossils and Fossil Collecting.
This website is mainly provided to give information on where and how to collect fossils. However safety warning are given some prominance. For example, although giving information about collecting fossils with a lump hammer "if you are lucky enough to arrive after fresh falls", it states that Burton Bradstock is not suitable for family fossil trips since the cliffs can be dangerous. There is a Safety Conduct Code. The website also contains various specific safety warnings including:
"No hammering the cliff - The unstable cliffs are very unpredictable and can fall at anytime, you won't find anything in the sands and can only find fossils in the Oolite blocks which come from the very top of the cliff."
The following comment in the website is relevant to the rock fall frequency:
"Locals wait months for 'Burton to fall', and when she does, her rich ammonite beds yield superb finds, bags to bring home. Cliff falls occur once every 2-3 years, fossils can be collected from the rocks on the foreshore or any scree slopes. After from ammonites, many other fossils can also be found, including echinoids, shark fins, bivalves and brachiopods."

[Note that in August 2012 the cliff was closed to public access after a fatal accident resulting from a rock fall on the 24th July 2012. It is not known if and when it will be open again.]

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Williams, R.B.G., Robinson, D.A., Dornbusch, U., Foote, Y.L.M., Moses, C.A. and Saddleton, P.R. 2004. A Sturzstrom-like cliff fall on the Chalk coast of Sussex, UK. Pp. 89-97 in: Mortimore R.N. and Duperret, A. 2004. Coastal Chalk Cliff Instability. Geological Society of London, Engineering Geology Special Publications, No. 20, 173 pp. ISBN 1-86239-150-5. [Not on Burton Bradstock but relevant to cliff falls there.]
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Wilson , V., Welch, F.B.A., Robbie, J.A. and Green, G.W. 1958. Geology of the Country around Bridport and Yeovil (Explanation of Sheets 327 and 312). With contributions on: The Purbeck Beds by F.W. Anderson, Palaeontology by R.V. Melville, and Groundwater by S. Buchan. London, Her Majesty's Stationery Office, 239 pp. Department of Scientific and Industrial Research. Memoirs of the Geological Survey of Great Britain.
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Woodward , H.B. 1887. Excursion to Bridport, Bothenhampton, Burton Bradstock, Bridport Harbour and Eype. Proceedings of the Geologists' Association, London, 9, 200-209.
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Wright , T. 1856. A descriptive catalogue of some of the species of ammonites from the Inferior Oolite of Dorset. Quarterly Journal of the Geological Society, London, 12, 309, 321.

" [end of 7.2 References and Bibliography - Printed Publications]

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APPENDIX - EXTRACTS FROM PRESS REPORTS ON THE ROCK FALL OF 24th JULY 2012 AT BURTON CLIFF.

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BBC-News-Dorset-25th-July-2012. BBC News Online:
Dorset Cliff Landslide: Body found in hunt for woman.
A body has been found under hundreds of tonnes of rocks which fell in a massive landslip from cliffs above a Dorset beach. The rocks came down on Tuesday afternoon [24th July, 2012} at Hive Beach near Freshwater Beach Holiday Park at Bridport. Dorset Police said the body is believed to be a 22-year-old woman who had been reported missing earlier. The body was found at 21:40 BST within the 10m (33ft) high pile of fallen rocks. A police spokesperson said: "Next of kin [of the missing woman] have been informed and family liaison officers are with them.
“We just saw a huge cloud of yellow dust from the cliff” Liz Rice Eyewitness. "At this time there are no further reports of missing people, and the search is now being stood down. "It is believed the incident was a tragic accident and our thoughts are with the family of the victim at this very difficult time."
The beach forms part of the historic Jurassic Coast - from Swanage in Dorset to Exmouth in Devon - sections of which have been crumbling into the sea for years. Last week, Dorset Council issued a warning to visitors and walkers of the risk of landslips following persistent heavy rain. A Maritime and Coastguard Agency spokeswoman said: "Portland Coastguard received a report of a landslide between Freshwater and Burton Bradstock at just before 12.30pm. "The landslide was reported to be 400m from Freshwater caravan park and the caller reported that a person was trapped under the fallen rocks." Three coastguard teams, helicopters and sniffer dogs were joined by police, firefighters, ambulance and lifeboat crews in the search and rescue effort. Eyewitness Liz Rice said: "We just saw a huge cloud of yellow dust from the cliff. "Clearly the some of the cliff had fallen on to the beach and within 20 minutes the emergency services had arrived." The incident comes two weeks after Somerset couple Rosemary Snell and Michael Rolfe were killed in a landslide, nine miles away at the Beaminster Tunnel.

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BBC News Dorset. 2012. Online.
Dorset cliff landslide: Tribute to Charlotte Blackman; Landslide at Hive Beach: The landslide happened on Hive Beach, just before 12:30 BST on Tuesday [24th July 2012]. Tributes have been paid to a 22-year-old woman who died after being buried under hundreds of tonnes of rocks following a landslip on a Dorset beach. Charlotte Blackman, of Derbyshire, was walking on Hive Beach near Freshwater Beach Holiday Park at Bridport when the rocks came down on Tuesday... Ms Blackman, her boyfriend and her father were all buried when the 160ft (49m) high cliff above them collapsed. The men were pulled free by bystanders but they could not locate Ms Blackman. Her body was found by emergency workers at 21:40 BST within the 33ft (10m) high pile of fallen rocks. Witnesses at the beach said Ms Blackman, from Heanor, had been seen walking directly under the cliff. ... Mr Blackman said: "She was on holiday with her whole family, her mum Rachel, dad Kevin, sister Sinead, little brother Mitchell, and boyfriend Matt. .."My brother and her boyfriend and her little brother were there when it happened. I understand the boyfriend got her little brother away into the sea to get him from it. Martin Cox About 400 tonnes of rock fell from the 160ft (49m) high cliff.... Search crews used sniffer dogs and specialist listening devices to try to find Ms Blackman amid fears of further rock falls at the site. Three coastguard teams, helicopters, police, firefighters, ambulance and lifeboat crews took part. The search was called off once her body was found as there were no further reports of missing people, police said. A spokesman added: "It is believed the incident was a tragic accident and our thoughts are with the family of the victim at this very difficult time." The inquest into Ms Blackman's death was opened and adjourned at County Hall in Dorchester earlier. ... Mick Stead, of Dorset Fire and Rescue, estimated 400 tonnes of rock had fallen in the "significant collapse" covering an area of 20m between Freshwater and Burton Bradstock. He said the recent weather was the likely trigger for the landslide at the beach. Witnesses reported seeing part of the cliff fall onto the beach, and then some minutes later more rocks fall on top of the mound. Eyewitness Liz Rice said: "We just saw a huge cloud of yellow dust from the cliff. "Clearly some of the cliff had fallen on to the beach and within 20 minutes the emergency services had arrived." The incident comes two weeks after Somerset couple Rosemary Snell and Michael Rolfe were killed in a landslide, nine miles away at the Beaminster Tunnel.


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BBC News Dorset, Online. 2012. Man dies after Swanage climbing accident. BBC news website: 24th August 2012.
A 32-year-old man has died in hospital after a climbing accident on the Dorset coast. The experienced climber, who was with his girlfriend at the time, was scaling Dancing Ledge in Swanage on Thursday afternoon. Police said he was rescued from the sea and flown to Dorchester County Hospital by Portland Coastguard helicopter. But he was pronounced dead shortly after arrival. His next of kin have been informed.

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Account from Inquest - by Euan Stretch (slightly shortened); Daily Mirror - 19th December 2012, p. 9. (Title - If I die, I want to go with my daughter)
The distraught boyfriend of a young woman buried alive by a huge beach landslide [rock fall] told yesterday how he and her father desperately battled to save her. Matthew Carnell described how 22 year old Charlotte Blackman disappeared beneath 400 tons of rock that fell "in the blink of an eye" from an unstable cliff. He managed to save her younger brother Mitchell, 12, by dragging him out of the way but he and Miss Blackman's father 45 year old Kevin failed to reach her despite heaving aside boulders "the size of haystacks"....
They repeatedly called out her name as they clambered over the 35ft high pile of rubble before they were dragged back by members of the public for their own safety.
David Warren, a canoeist, told an inquest how he had been coming out of the sea when he witnessed the drama. He described how Matthew, also 22 and Kevin were covered in dust. "I pleaded with them to get back," he said "I screamed at them as rocks were still falling.
The hearing was told how the family had been on holiday at the Freshwater Beach Holiday Park at Burton Bradstock, Dorset, when the tragedy happened on July 24th. Kevin, his wife Rachel, Charlotte, Matthew and Mitchel had spent the morning on the beach. They were walking back to the caravan park for lunch when Matthew noticed two small stones falling down the cliff.
He said "Almost simultaneously I saw about half the cliff face collapse. It happened so fast, as in the blink of an eye. We had no time to get out of the way. I grabbed Mitchell and ran into the sea. A large dust cloud appeared and I couldn't see for 20 seconds. I went to the area where the cliffs had fallen. I sent Mitchell away. There were boulders the size of haystacks. I couldn't see Charlotte. Me and Kevin were calling for her and trying to move the rocks.
I was aware people were shouting and telling me to get away. It was complete chaos. All I could think was I wanted to find Charlotte and try to get her out of there. I tried for five minutes. I couldn't move any more of the rocks. The body of Charlotte, who recently gained a first-class honours degree in education studies, was recovered nine hours later. A postmortem revealed that she died from multiple crush injuries. On the morning of the tragedy, there had been up to four minor landslides. Warning signs about falling rocks had been erected at the holiday park..
Mr Sheriff Payne, coroner for West Dorset, recorded a verdict of accidental death. He said "It was a sudden act of nature nobody could have expected at the time. Charlotte was closest to the cliff. She died instantly. There was no chance of her surviving it."
He told the family that he would write to the holiday park urging them to improve their warning signs. Since her death, her parents have set up the Charlotte Blackman Memorial Fund to raise money for autism services.

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Dorset Echo - Coroner's Inquest - 20th Dec. 2012 Charlotte Blackman
(Extracts from Article - shortened); Wednesday 19th December 2012 in News; By Rachael Burnett)

A verdict of accidental death was recorded for 22-year-old Charlotte Blackman. Around 400 tonnes of rock fell at Burton Bradstock. Holidaymaker Charlotte Blackman was killed instantly by a 'sudden act of nature' that no one could have predicted, an inquest was told. The 22-year-old from Heanor, Derbyshire, died in a massive landslide [rock fall] at Burton Bradstock beach on July 24, while staying with her family at Freshwater Beach Holiday Park. Miss Blackman was spending a day at the beach with her father, brother Mitchell, his school friend, and her boyfriend, while her mother Rachel remained at their caravan park nearby. She was only seven feet away from her father and her boyfriend when she was buried by 400 tonnes of rock, the inquest at County Hall in Dorchester was told. Mr Blackman said he shouted for the group to get out of the way seconds before she was buried. He said: "I was about seven feet from Charlotte when it happened. I heard a noise, looked up and saw a bit of dust come out a crack [i.e some movement in a joint]. I shouted run, turned around and she was gone."
Several witnesses told the inquest they saw smaller cliff falls before the fatal landslide but Mr Blackman said they did not see any. Witness David Warren said he shouted a warning to the group not to go down the beach where he had seen a landfall but her family say they did not hear him.
Mr Blackman said: "I wouldn’t have taken my kids near it if I had seen a landslide. “If I knew there were cliff falls we wouldn’t have been there. We heard nothing and saw nothing – it was just a sunny day when we walked along the beach."
A post mortem report stated that Miss Blackman’s death was caused by non-survivable injuries and would have been instantaneous. Dorset coroner Sheriff Payne said that the tragedy could not have been predicted. He said: "Charlotte has died as a result of an accident, an entirely unpredictable incident. Her father Kevin was also injured and it is fortunate he didn’t suffer more serious injuries. This was a sudden act of nature that nobody could have expected, in particular those poor members of her family."
"The only warning was a couple of stones coming down and then the substantial rock fall occurred. The post mortem report confirms that Charlotte died instantly, there was no chance of her surviving or of anyone being able to pull her out alive.
Mr Payne said the evidence shows that the cliffs are totally unpredictable and that the weather does not help in pre-empting landslides. He said the National Trust, which owns a stretch of the beach where it happened, is doing all it can to warn visitors of the dangers of the unstable cliffs. Boyfriend was just 10ft from Charlotte... Matthew Carnell, pictured, told the inquest of the moment when she was buried - just ten feet away from where he was standing. He said: "I saw two small stones falling and then half the cliff collapsed. It happened so fast, in the blink of an eye, there was no time to get out of the way or do anything. There was a crashing sound and a large dust cloud. Some of the rocks were the size of haystacks. I couldn’t see Charlotte. It was complete chaos, I was in a panic.
Earth scientist Richard Edmonds, who has been studying the West Dorset Jurassic Coast for a number of years, told the inquest that there is a constant risk of land falls in the Burton Brad-stock area. He said: "The cliffs are in all sorts of states of movements. They can sit there for years and then come down quite suddenly. It's a very difficult situation. There is clearly a risk but no evidence of any other injuries in the last 25 years and many people have enjoyed the cost in those years. "This landslide happened two weeks after very heavy rainfall. However, the risk is a constant – it could happen at any time and is not necessarily weather related. The coast path is closed at Burton Bradstock now because there are concerns. If it wasn’t for this horrible event that wouldn’t have happened. It could be months or years until another fall. It's always dangerous to walk under a cliff, it's a difficult thing to manage. I don't think the risk will ever change, it's a constant. I don’t think people would respect the actions of putting up signs unless this tragic accident had happened. Without it the National Trust would have had the signs ripped down and burned.
Leonard Muggeridge was fishing from his boat when he saw the landslides, he told the inquest. He said: "At about 12.30pm I heard what sounded like gunfire, there were clouds of dust and debris. Lots of rocks had been deposited at the base of the cliff, about two or three industrial skip loads. The bottom third of the cliff [i.e. Bridport Sands] had come down and the top part [Inferior Oolite etc]was overhanging. Around 20 minutes later I heard more of what sounded like gunfire. "The rest of the cliff, except for the top 15 feet [Fullers Earth], seemed to have come down. The rocks had fallen down to the edge of the sea." [i.e. the second fall, of Inferior Oolite sent blocks to the edge of the sea]
Dorset coroner Sheriff Payne, said he will be writing to Freshwater Beach Holiday Park to make sure warning signs are placed on its land. He said: "There’s a terrible balance between individual freedom and potential dangers. Miss Blackman’s family says the signs were insufficient and it is correct that they would not have seen the National Trust signs. I am going to make a report to the Freshwater Holiday Park that they will have to make signs more visible and in locations seen by people intending to go to the beach. The National Trust appears to be doing the best it can with an ongoing task that is just impossible."


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ITV-News. 2012.
Landslide Death at Burton Bradstock. Landslide death woman named. A young woman who died after being buried by tonnes of rock following a landslide on a beach in Dorset was named today as Charlotte Blackman from Derbyshire. The incident took place at the Freshwater Beach holiday park at Burton Bradstock beach. Latest ITV News reports: Rescue workers at the scene of the Burton Bradstock Landslide in Dorset. Woman's body found after Dorset landslide 3:59pm, Wed 25 Jul 2012. Charlotte Blackman's colleague pays tribute to 'wonderful woman'. Charlotte Blackman, 22, died after being buried by tonnes of rocks on a beach in Dorset. Charlotte Blackman was a volunteer with Derbyshire Autism Services Group, where she worked one-to-one with people with autism, including children, and help to give their families a break. The group's manager, Margaret Reeve, paid tribute to Miss Blackman today and said she was a "wonderful, wonderful young woman". "She was a very genuine person, very warm, very funny, and had a great deal of time for people. She was a very good volunteer," she added. [A long series of photographs and brief reports from various people regarding this tragic accident follow. This is a thorough account:]
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Salkeld, L. 2012. Young woman who was buried by landslide after 400-ton Dorset rock fall is named by her uncle. Mail Online, Wednesday, 25th July 2012. By Luke Salkeld.
The full article is at: Young woman who was buried by landslide after 400-ton Dorset rock fall.
Extracts only:
Charlotte Blackman, from Derbyshire, was walking on the beach at Burton Bradstock with her boyfriend and his father. All three were trapped by huge rockfall at 12.30pm from 150ft cliff. The men escaped but Miss Blackman was crushed by second landslide. .. Her body was found at 9.40pm. Stretches of the British coastline are cracking up in one of the most 'extreme' summers on record. Heavy rain followed by periods of strong sun thought to be responsible.
A young woman who died after being buried by 400 tons of rock following a landslide on a beach in Dorset was named by her uncle today.Charlotte Blackman, from Derbyshire, was trapped by a 35ft-deep pile of rubble along with her boyfriend and his father shortly after 12.30pm yesterday, while they were out walking in Burton Bradstock. The two men were helped out of the rubble by others on the beach but Miss Blackman was directly under the fall and could not be saved...
As time ticked on, the chances of her survival became increasingly remote. Dorset Police confirmed a body had been found at around 9.40pm. A spokesman said: 'The body is believed to be that of a 22-year-old woman reported missing earlier in the day following a landslide.
At this time there are no further reports of missing people at the location and the search operation will now be stood down.....
They said they had just been walking along the beach and they didn't hear anything. Then all of a sudden there was this huge landslide which fell down on them... The beach, which is close to the Freshwater Beach Holiday Park, had been filled with day trippers enjoying yesterday’s fine weather. The location of the cliff landslide by the caravan park in Burton Bradstock, near Bridlington in Dorset.
The cliffs along the Jurassic Coast have become severely unstable in recent weeks due to heavy rain followed by dry and sunny conditions, which have led to them cracking and crumbling away.
Mr Rafferty added: It was the first landslide that trapped the woman. The father and the boyfriend were on top trying to get her out, I could see them trying to move rocks. They were clearly in shock and were frantically pulling the rocks out of the way. Then there was the second landslide and luckily they got out of the way.
Mick Stead, from Dorset Fire and Rescue Service, said last night: There was a significant landslip. About a 20-metre (60ft) stretch of the coastal path has given way. We estimate that about 400 tons of mud and rock has fallen from the top and down on to the beach.....
The council said the western end of the Esplanade at West Bay, near Burton Bradstock, was closed at the weekend 'due to concerns about continuing land stability in the area following the exceptional wet weather. The council, posting on its website on June 20, said it had found large overhanging rocks at the top of the cliff at the western end of West Bay Esplanade, which appeared 'ready to fall'.....

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Taylor, M. and Morris, S. 2012. Woman trapped under rocks after cliff collapses. The Guardian Newspaper, Wednesday, 25th July 2012.
By Matthew Taylor and Steven Morris. (with one photograph of a rock fall and rescuers on the beach at Burton Bradstock).
Extracts: A young woman was left trapped yesterday after a cliff in Dorset collapsed, sending hundreds of tonnes of earth and rock onto a busy beach. Horrified onlookers - including the woman's father and boyfriend - tried to get to her before another huge section of the cliff gave way, forcing them back. ..... Mick Stead, from Dorset fire and rescue service, said a 20 - metre stretch of the southwest coast path had given way. We estimate that about 400 tonnes of mud and rock has fallen from the top and down onto the beach. ... Dorset police were called just before 12.30 pm and told that a person had been trapped under the landslide 400 metres from the Freshwater Beach holiday park at Burton Bradstock, near Briport. Witnesses said that there was an initial landslide quickly followed by a second, bigger one. .... Fisherman Dave Smith, 42, said "I was fishing on the beach and all of a sudden I heard a great rumble and there was a huge amount of dust. I saw part of the cliff had slumped into the sea [was it at high tide, since photographs at low tide show the rock fall extending only half way down the beach?]. ... I expect that all the rain we have had followed by the hot spell has caused the cliff to crumble. .. The cliff forms part of the Jurassic Coast world heritage site and the landslide came on one of the hottest days of the year, just a fortnight after severe flooding left much of the area under water. Two weeks ago, Somerset couple Rosemary Snell, 67, and Michael Rolfe, 72, were killed in a landslide at the Beaminster Tunnel nine miles away... Four days ago, Dorset council posted a statement on its website warning walkers and fossil hunters to "beware of landslides and other hazards" following recent bad weather. It said that the exceptionally wet weather of recent months had led to a "heightened risk of rock falls anywhere and at any time along the coast"... A spokesman added on the 20th July: "The advice is to stay well away from the cliffs at all times and to beware of mudflows and quicksand, especially when the tide is coming in, as it is possible to be cut off from the normal exit points to and from the beaches..... Dorset fire and rescue yesterday said the extreme weather may have contributed to the landslide an the authorities would now consider closing other beaches along the stretch of coast. [end of article]

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