West, Ian M. 2014. The Eocene Cliffs of Bournemouth Dorset - Geology of the Wessex Coast. Internet site: www.southampton.ac.uk/~imw/bourne.htm. Version: 28th March 2014.
Bournemouth cliffs - geological field guide
Ian West,
Romsey, Hampshire

and Visiting Scientist at:
Faculty of Natural and Environmental Sciences
Southampton University,
Website hosted by iSolutions, Southampton University,

|Home and Contents | |Field Guides - Introduction |Sandbanks Peninsula |Brownsea Island, Poole Harbour |Hengistbury Head |Bibliography of the Geology of Hengistbury Head webpage. |Highcliffe, Barton & Hordle Coast Erosion |Highcliffe, Barton & Hordle Bibliography |Sandbanks Peninsula |Studland, South Haven Peninsula

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A general view of Bournemouth Pier, Bournemouth, Dorset, and the re-nourished sandy beach, as seen from a helicopter, 6th July 2013

The cliffs between Middle Chine and Bournemouth Pier, Bournemouth, Dorset, 6th July 2013, helicopter view

View towards Bournemouth Pier, Dorset, from west of Branksome Chine, showing largely vegetated, Eocene cliffs and a broad sandy beach

Cliffs of Bournemouth, Dorset, seen from Sandbanks

View of Bournemouth Pier from Boscombe Pier, late on a winter's day, showing wide sandy beaches and timber groynes

Poole Head from Sandbanks with Eocene cliffs beyond, Dorset Branksome Sand at Canford Cliffs, west of Branksome Chine, Dorset

A view of Bournemouth in its early days of development and when the cliffs were still a natural source of supply of sand and gravel to the beaches and not shut off by a seawall and promenade

INTRODUCTION

General

The 1891 version of the geological map of Bournemouth, Dorset, with additional notes

Poole Head from Sandbanks with Eocene cliffs beyond, Dorset Old Harry Rocks seen across Hook Sand from Sandbanks, Dorset during a southwesterly gale

The Bournemouth Cliffs and the Sandbanks Peninsula are part of Poole Bay, a broad shallow embayment on the central south coast of England. It is mostly a area of sandy beaches and, although occasionally the sea can be in stormy condition as shown in the right photograph, the coast is protected to some extent from the prevailing southwesterly winds by the promontories of the Isle of Purbeck, particularly that of Old Harry Rocks and Ballard Point (visible here). The Bournemouth cliffs (left photograph) are notable for sands and clays of Eocene age and in which some remarkable plant fossils have been found. Until about the beginning of the 19th century these cliffs were well-exposed, attractive yellow cliffs which supplied sand directly to the Bournemouth beaches. This area then became heavily developed and expanded into the present holiday town. A consequence of the development was the construction of a promenade and sea-wall which now covers the base of the cliffs. With lack of erosion are now quite largely vegetated and they are controlled and drained by civil engineering works. Although most of the cliffs are now generally inaccessible for detailed geological studies, some features of interest can still be seen. It is well-worth taking a walk along the foot of the cliffs and considering the geology. Furthermore an extension of this coast in relatively natural form still exists not far to the east at Hengistbury Head , described in a separate webpage. At the other (western) end of the bay, and at the entrance to Poole Harbour, is the |Sandbanks peninsula, once a sand-dune-covered sand spit, but now developed for expensive housing. The beach is of interest here and the rock groynes have relics of fossil trees, stromatolites and other fossils and structures from the Purbeck and Portland strata of the Isle of Portland, the source of the rocks. From Sandbanks there is a ferry across the narrow entrance to the natural and undeveloped Studland or South Haven Peninsula , also described in a separate webpage. This is a classic area for geomorphological and environmental studies.

Knowledge gained from the Bournemouth cliffs is of great interest and is relevant to understanding the geology of the Eocene strata in the region. In historic times the Bournemouth cliffs were once used for mining of copperas (alum-type sulphate minerals) because of the pyrite content. They are most famous, though, for their fossil leaves which seem to indicate that in Eocene times there was here an unusually warm environment even thought the palaeolatitude would normally suggest temperate rather tropical conditions .

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INTRODUCTION;

The Chines of the Bournemouth Cliffs

The Chine of Bournemouth are well known. These are steep sided small valley on the coast. The word comes from Saxon "Cinan" meaning a gap or yawn (Wikipedia). If the origin of the name is Saxon then it is an indication these coastal geomorphological features are quite old in historical time. Of course they are very new in geological time!

These small coastal valleys are developed in easily and quickly eroded sands and clays. At Bournemouth they are in Eocene strata. In the Isle of Wight they are present in both Eocene and Cretaceous, particularly Wealden and Lower Greensand cliffs. Characteristically they contain a small stream or rivulet which is adjusted at its mouth to the present beach level. Thus they are convenient access routes to the shore without having to descend steep cliffs. Although many are still in this form, particularly at Bournemouth, where there is a sea-wall and promenade, others have been eroded back into hanging valleys. This erosion and eventual destruction is most marked on the southwest coast of the Isle of Wight where there is rapid coast erosion. It is high there because the weak coast faces southwesterly wind and wave action. As a result access to that coast is now becoming increasingly difficult. Thus it should be noted that on exposed coasts with rapid erosion chines are not keeping pace and are progressively being lost. They are not, therefore, as was argued by Bury (1934) the result of rapid coast erosion. They may have formed in a pause following rapid coast erosion.

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The chines of Bournemouth from west to east are as follows:

(Poole Head)

Flaghead Chine
(there was a watch tower on cliff top on the east side)

Canford Cliff Chine
(In 1882 this was Sugar-Loaf Chine, named after a large conical hummock, resembling an old fashioned sugar-loaf).

Branksome Chine (present name)
(but this was Branksome Glen or Watering Chine in 1882)

Branksome Dene Chine
(listed as Branksome Chine in 1882)

Alum Chine
(Listed as Alum Chine or Broad Chine in 1882)

Middle Chine

Durley Chine
(Great Durley Chine in 1882)

Little Durley Chine - no longer exists.
(in 1882, shown as a shallow indentation, and probably at the site of the present cliff path or the lift)

(Flag Staff on the cliff top in 1882)

The Bourne Valley.
At Bournemouth Pier - a long stream valley, not a true "chine".
(There is Head, peat deposits and a submerged forest of carbonised wood, under the pier approach. The Bournemouth Pier peat deposit and submerged forest contains stumps of pine, together with birch and alder (White, 1917). It lies on gravel, presumably Pleistocene. It is most likely to be of about Neolithic age, but it could be older. It shows that the Bourne Valley is not a recent "chine" but a stream valley with a long history.)

Step Chine (no longer present)
(this was a small recess at the cliff path or zigzag not far to the east of Bournemouth Pier).

Boscombe Chine (major chine)

Honeycomb Chine (no longer exists)
(This was a short distance east of Boscombe Chine. It was a small, picturesque, chine, a shallow indentation, with a honeycomb-like structure. It was notable for abundant fossil remains of Nipa, the Vietnam Swamp Palm in the Eocene strata.)

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The Pleistocene palaeovalleys made by rivers flowing across Poole Bay and Christchurch Bay, English Channel, modified after Velegrakis et al. 1999

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In general the chines probably commenced as minor upper tributaries of the original offshore continuation of the Branksome Chine stream and the Bourne Stream which would have headed generally south in the direction of a former river channel in Poole Bay. See See Velegrakis et al., (1999), and a sea-floor map, based on that work, and which is reproduced in another part of this webpage. The small streams of particular chines were heading for either Palaeovalley Complex 2, flowing south directly south of Bournemouth or Palaeovalley Complex 1, ie. the Piddle - Frome extension (coming out of Poole Harbour).

In contrast, in the old accounts the chines were wrongly regarded as the upper parts of former tributaries of the Solent River (Bury, 1934). However, new evidence shows that there was actually no eastern flowing Solent River immediately to the south of Bournemouth in the late Pleistocene (although there might have been at an earlier date). The Solent River was not there and there is no fossil channel of an eastward flowing river at a geologically recent date, i.e. at the time just before the chines were formed.

Bury (1934) commented on the supposed early history of the chines. Ignoring, now, his older view about the Solent River we can consider his other aspects of his discussion.

"The rate of regression of the shore-line [at Bournemouth] has probably varied from time to time, but at the end of the last century, before the erection of the present sea walls, it amounted to about 9 inches [23 cm] per annum at the western end of the bay [Branksome, Canford Cliffs etc.] to about two and a half feet (76 cm) per annum at Southbourne [i.e. fast like Barton-on-Sea]. This advance of the sea necessarily shortened the valleys, and compelled the streams in them to cut their beds down to lower levels and steeper gradients; and it is this comparatively rapid adjustment to changing conditions which has led to the formation of the ravine-like chines."

It is true that a phase of rapid coastal erosion was probably the starting point for the developement of the chines. The ends of the small streams became closer to their head because of coast erosion. The gradient of part of the stream had to change. It did this by development of a new knickpoint, i.e. the thalweg changed because of a phase of rapid coastal retreat.

However, if the coastal retreat is very rapid the stream cannot adjust to sea-level. This is happening of the southwest coast of the Isle of Wight where there are chines cut into Wealden strata. Rapid coast erosion produces hanging valley, and in due course chines are completely lost. This is common in many places with soft rock, but at Bournemouth there has been is a sea-wall and promenade since 1914. Thus the chine situation at Bournemouth is, in a sense, fossil. The coast has not retreated since 1914. Prior to that date there had to be a phase of rapid coast erosion. However, there also had to be a subsequent pause in coastal retreat so as to allow downcutting at the chines. In this respect I would disagree with the old theory of Henry Bury.

So the general pattern is rapid coast erosion, then a pause in coastal retreat. Chines then develop. If a new phase of rapid coast erosion occurs then, as on the Isle of Wight now, the chines are eroded away. They become hanging valleys, finally almost disappearing. Access to the coast is thus greatly reduced. This is current situation, except at Bournemouth where old the sea wall and promenade still survive (due to protection by the Isle of Purbeck from the worst effects of southwesterly storms)

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INTRODUCTION

Geomorphology - Beach Processes.

Sand Sediment Transport - Present and Future

Present sand sediment transport on the beaches of Poole Bay, Bournemouth, Dorset, and possible implications for the Sandbanks Peninsula in the future

The topic of supply, movement and loss of beach sand on Bournemouth beaches has been well studied by SCOPAC. A very simplified diagram is provided above, but it recommended that the full SCOPAC MAP be studied. It contains quantitative data, not given here. For technical information on this topic go to:

SCOPAC - Sediment Transport. SCOPAC - Standing Conference on Problems Associated with the Coastline. There are many sections in this important publication. There is a an index map at: Sediment Transport Study - map showing areas.

More specifically for Poole Bay, Bournemouth and Sandbanks visit the map with detailed sediment transport information at:

Poole Harbour Entrance to Hengistbury Head">

In general terms the sandy beaches of Bournemouth and Poole Bay have derived their sand from the erosion of the Eocene strata in the cliffs. Sandbanks has in particular resulted in part from a good sand supply from the Branksome Sands, forming the cliffs of the western part of Poole Bay, particularly from Durley Chine westward. The Branksome Sand Formation is 70m thick; it takes its name from Branksome Chine [SZ 069090] and is of Bracklesham age Bristow et al. (1991).

The Boscombe Sands, 20 to 27m thick, are present in the Bournemouth Cliffs from Durly Chine eastward, past Bournemouth Pier and on to Southbourne. They reappear at Hengistbury Head (Bristow et al., 1991). In the past, before the construction of the promenade from about 1914 onward both the Branksome Sand Formation and the Boscombe Sand Formation contributed much sand to the Bournemouth Beaches, and made them a favourite bathing area. In addition there was some supply of both subangular flint pebbles and some sand from the Pleistocene gravel terraces, just a few metres thick at the tops of the cliffs.

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Some Sea Defence History - Bournemouth Sea Front

Rapid erosion has long been a problem at Hengistbury Head, and the promontory is much smaller than in the past. Gardner (1879) refers to a loss of 100 yards in 30 years (i.e. roughly 3m per annum, similar to the maximum figure for Barton-on-Sea). A coastguardman estimated that 60 yards had gone in 16 years (almost 4m. per annum). Hengistbury Head does not suffer rapid erosion now, not at all, because the regularly replenished sand from Bournemouth travels by longshore drift east to Hengistbury Head. I know, myself, from living at Southbourne, about 50 years ago, that rapid erosion was common there and Hengistbury Head in the past.

Now the cliffs of Bournemouth are no stronger or more resistant than the cliffs of Hengistbury Head and Southbourne. There are differences though. The Bournemouth cliffs are more protected from southwesterly storm winds and waves by the Isle of Purbeck than is Hengistbury. The sea-wall and promenade at Bournemouth was built in 1914 (and is not popular with geologists!).

Prior to that the erosion was probably fast and the sandy cliffs supplied the sand to Sandbanks and on to Studland. The cliffs were not necessarily all publicly accessible in Victorian times. There were private estates on the cliff top. There was an iron ladder down the cliff at one point between the present locations of Bournemouth and Boscombe piers. Lord Portman, who at one time lived in Portman Lodge, Exeter Road, arranged pile-driving at the foot of the cliff and built a concrete road up the face of the cliff (but I do not know where this was). The sand dunes at the top of the cliff and sand from the cliff were constantly falling on the concrete road according to Gardner writing in 1879.

A general feature of the Bournemouth cliffs, still visible today, is that the Branksome Sand Formation occurs in steeper, almost vertical lower cliffs, while the white and friable Boscombe Sand Formation slopes back at a considerable angle. This again was reported by Gardner (1879) and is still to some extent true today, although now the cliffs are mostly heavily vegetated.

In 1914 just before the sea wall was constructed, it was estimated that the coastal recession rate between Bournemouth and Boscombe was between 12 inches (30 cm) to 18 inches (45 cm) per annum Ord et al(1914) . It was only towards 1914 that the cliffs assumed almost vertical faces. Some fifty years earlier (about 1864) the cliffs were less steep and a lady on horseback rode up the cliff-face between the Zigzag and Boscombe [there is probably a byelaw against doing that now!]

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STRATIGRAPHY:

Introduction

A chart showing lithostratigraphic schemes for the Palaeogene strata of the Bournemouth and Poole area, including Brownsea Island and Barton-on-Sea

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LOCALITIES - Sandbanks

Please go to: |Sandbanks Peninsula webpage.

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PALAEOBOTANY - The Bournemouth Leaf Beds

Eocene flora - leaves

Leaf beds in the Bournemouth cliffs Bournemouth Pier Approach in 1899 Leaf bed near Durley Chine -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
The central photograph is modified from part of an old photograph reproduced in Edwards (1981) and the right photograph is from Ord (1914). Both images have been tinted.
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Fossil leaves from the Pipe Clay Series of the Poole Formation, Poole Harbour and Purbeck area, Dorset

The Beaulieu River at Ipley in flood on 10 November 2008, transporting leaves from the New Forest to the Beaulieu River Estuary, Hampshire, England

An image above shows leaves from the "Pipe Clay Series" of the Poole Formation from around Poole Harbour and in the Isle of Purbeck. These leaves are slightly older than those from the Bournemouth leaf beds, but are still from the Bracklesham Group of the Eocene. The leaves were presumably washed down the rivers by floods, as happens in the New Forest nowadays, but on a larger scale and onto a major delta.

The Middle Eocene succession in the cliffs at Bournemouth is mostly between about 42 and 50 million years old, being largely Lutetian and Auversian, but ranging up to Bartonian at Hengistbury Head. The Bournemouth to Boscombe Cliff section was by far the most interesting and important display of Eocene beds in the district of the Hampshire Basin, in the opinion of William Ord in 1914. Unfortunately the completion of the Undercliff Drive, before 1914, practically closed it to geological investigations, although sedimentological studies have been made since (Plint 1980; 1982; 1983a; 1983b; 1988). Mr Starkie Gardner wrote important papers describing the coastal exposures in 1879 and 1882 with information on the plant remains. The cliff sketch above based on Gardner's classic work shows the positions of the main leaf beds. The central photograph shows the limited development of the Bournemouth coast at the turn of the century (1899), while the right photograph shows a leaf bed near Durley Chine a little later (pre-1914). These old photographs are to set the scene of the Bournemouth cliffs as they once were. In the past there were good geological exposures like those at Hengistbury Head or Hordle Cliff at the present day. Illustrations of this webpage show something of the locations and contents of the leaf beds. Further information on leaf discoveries is given in the sections below on specific parts of the coast.

The relatively recent state of the cliffs in terms of exposures is shown by Daley and Crewdson (1987). They have provided a cliff diagram showing the small percentage of cliff area that remains uncovered with some information on the strata visible, and in the text, comments on the exposed sections..

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PALAEOBOTANY:

Palaeoclimatic Implications of the Bournemouth Eocene Flora

The hot, wet, forest and delta-swamp palaeoenvironments in which the Bournemouth leaf beds of the Eocene originated (reconstructions, based partly on Webster Smith ,1931),

A modern tropical swamp environment with the stemless palm Nipa, the fruits of which occur in the deposits of the Eocene, Poole Delta at Bournemouth, Dorset and elsewhere in the region

The latitude of Bournemouth is now almost 51 degrees N and the modern vegetation is of temperate type. The Bournemouth leaf beds, of Middle Eocene age and deposited between 50 and 42 my ago, originated in a palaeolatitude which was at about 40 or perhaps more accurately 42 degrees N ( Smith and Briden, 1977 ) and they are notable for containing both temperate and tropical types of plants. This is a latitude like that of central Spain at the present day, not that of equatorial rain forests, and the presence of tropical plants is an anomaly. Plants of such a warm origin are particularly abundant in the Lower Eocene, London Clay (Daley, 1972) . The Bournemouth leaf beds of the Middle Eocene originated slightly later but contain some tropical plant remains, such as Nipa (see the stemless palm in the reconstruction of Webster Smith, 1931, above), like those in the London Clay. Reid and Chandler (1933) concluded that the London Clay flora compared most suitably with the present day vegetation of the Indo-Malayan region. This, they suggested, indicated a Tropical Rain Forest climate during the Early Eocene times in southern Britain, with a mean annual temperature of 21%° C (although nearer to 25-26%° C according to Richards, in Chandler, 1964 ). Doubt, however, arose as to whether truely tropical conditions could have existed at such a high palaeolatitude (Daley, 1972) . A further problem is the occurrence in the London Clay of 11.5 %% of purely extra-tropical genera and it should be noted that other genera are present which live in both tropical and extratropical conditions at the present day. Thus there was a mixture of climatic types of vegetation, both during deposition of the London Clay and during depostion of the Bournemouth leaf beds.

The comments of Daley (1972) , below, refer specifically to the London Clay of Early Eocene age. The Bournemouth leaf beds of Middle Eocene age present much the same problems and his conclusions are relevant to the environment around Bournemouth during middle Eocene times:

"It is suggested that the mixture of tropical and extra-tropical plants may have resulted from a type of climate not represented at the present day. The absence of frost allowed tropical plants to spread into higher latitudes, where they would, during cooler geological periods, have been vulnerable to low winter temperatures. Higher rainfall throughout the world during the Eocene also facilitated the poleward spread of tropical plants, since at the present day precipitation is the main factor limiting their poleward spread. Tropical plants would have become established in low-lying damp areas near rivers and lakes where adaphic moisture supplemented rainfall and where humidity was high. Under such conditions of abundant moisture supply, temperatures need not have been truely tropical. Further away from the rivers and lakes, on slightly higher land, temperate plants could have grown under somewhat less humid conditions."

The Bournemouth Middle Eocene strata were mostly deposited from about 50 to 42my, a little after the London Clay with its very tropical floral aspect. Nevertheless warm "greenhouse" conditions would have existed at this time according to current theories of content of carbon dioxide in the atmosphere. Relevant research by Dr Paul Pearson and Professor Martin Palmer was reported in the journal Nature. They used a new technique to establish CO 2 levels in the ancient atmosphere, analysing the shells of planktonic organisms that once lived near the surface of the ocean. This enabled them to establish past seawater acidity, which in turn was dictated by the amount of atmospheric CO 2 . The researchers estimate that between about 60 and 52 million years ago, CO 2 concentrations reached more than 2,000 ppm. But from about 55 to 40 million years ago, there was "an erratic decline", which may have been caused by a reduction in CO 2 emissions from ocean ridges and volcanoes, and by increased carbon burial. Thus the Eocene had a very warm, ice-free world, particularly in the early part when the London Clay was deposited but the temperature had not fallen much when the Bournemouth leaf beds were deposited. The "Hampshire Crocodile", actually an alligator named as Diplocynodon hantoniensis, flourished at the end of the Eocene and its bones are found at Hordle Cliff. The temperature must have been still moderately warm at that time for the famous Hampshire reptile to lived, but cooling was just beginning and the first winter frosts in this area may have appeared in the Oligocene.

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Clay Mineral Distribution

Clay mineral distributions in the Hampshire Basin, based on the work of Gilkes (1968), with some further palaeoenvironmental interpretation

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LOCATIONS:

Poole Head, Branksome and West of Bournemouth Pier

[See also:

Sandbanks Peninsula

Brownsea Island, Poole Harbour]

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Poole Head and the Canford Cliffs area, Bournemouth, Dorset, a helicopter view in 2013

Promenade and sea-wall at Canford Cliffs, west of Branksome Chine, Dorset

Branksome Sand at Canford Cliffs, west of Branksome Chine, Dorset

Planar Cross-stratification in the Branksome Sands, Canford Cliffs, Dorset

The Branksome Sand Formation of the Bracklesham Group (Bristow, Freshney and Penn, 1991) is shown here in the isolated but quite good exposure at Canford Cliffs, west of Branksome Chine. These strata were once known as the Bournemouth Freshwater Beds of the Middle Bagshot Sands. The Branksome Sand is 70m in thickness and named after Branksome Chine (map reference SZ 069090) (Bristow, Freshney and Penn, 1991). The Branksome Sand occupies most of the cliff at Canford Cliffs and thence descends eastward in the cliff with the gentle easterly dip. The uppermost part (G), or the Bournemouth Marine Beds contain some marine molluscan remains. These strata extend as far as Southbourne at the foot of the cliff. The lower part, the Bournemouth Freshwater Beds (cycles A to F discussed below) contain plant remains but no marine macrofossils (but see the memoir re dinoflagellates). They have not been recognised far to the east of Bournemouth Pier. The age of the Branksome Sands may be disputed but is probably somewhere near Auversian or Upper Lutetian (equivalent to an upper part of the marine Bracklesham Group further east - perhaps the Selsey Formation).

The Branksome Sand Formation consists of seven fining-upward cycles, of which seven were lettered A to G in ascending order by Plint (1983b) . The right photograph above shows some of Plint's cycles, although the details are not clear without a close study of the section. An idealised cycle (and note well that is idealised and in practice not all parts may occur) commences with a very coarse-grained sand, often containing clay clasts, resting on an erosion surface. This is succeeded by coarse- to medium-grained sand showing large-scale, planar cross stratification (look at the photographs. You can clearly see planar cross-stratification. What was the general current direction here?). This passes up into medium-grained sand in which the cross-bedding is on only a decimetre scale. The cycle is capped by interbedded fine-grained sand and silty clay (Bristow, Freshney and Penn, 1991). Cross-bedding directions are surprisingly variable and it is a pity that they do not make a simple pattern.

In terms of composition the sands consist mainly of quartz, with some flint grains which are more noticeable in the coarser-grained sands according to (Bristow, Freshney and Penn, 1991). Remember that the palaeoclimate and palaeoenvironment, although theoretically warm-temperate, was in some respects almost tropical in type. With this in mind you may not be surprised to observe that this particular quartz-arenite is mineralogically mature. However, this is probably not the complete explanation. Think, for example, about the Namurian "Millstone Grit" of the north of England. That came from an equatorial environment yet, containing much feldspar, is not as mature as the Branksome Sand. Apart from the palaeoclimate there was likely to be another factor with regard to the Eocene sand, and this was the extent of reworking. Jurassic and Cretaceous sand were probably exposed to the west in Eocene times and the Trias was an obvious source of quite mature sand. We will leave the maturity topic here but it can pursued, if required, by consulting the heavy mineral literature (is there garnet - a common New Red indicator?).

To see a very good section of the Branksome Sand elsewhere and an indication of just how the Bournemouth appeared before the construction of sea defences go to:

Brownsea Island, Poole Harbour webpage.




The average grain size of the sand is medium - 253 microns (1.98 ø) but ranges from coarse to very fine. It is in general, moderately sorted (although varying) and slightly positively skewed.

More on the Fossil Leaves

Gardner commented that cliffs consist of yellow or whitish sands containing occasional masses of clay or loam, in which were found lignite and rarely leaves of plants. The clay usually appears in lenticular masses, but occasionally occurs in dark carbonaceous beds, sometimes a hundred metres in extent (see illustration). Pockets of impure china clay occur frequently here, but become rarer as Bournemouth Pier is approached.

The left-hand image below shows the type of preservation of the leaves in clay, in this case white pipe clay. This particular specimen found in 1882, comes from the Bagshot Beds of Alum Bay and is about 8 cm in length (modified from Kirkaldy, 1967 ). The other illustrations below are provided to show some of the variety of leaves that have been found in the Middle Eocene strata; some come from Bournemouth, some from Alum Bay on the Isle of Wight and some from the Corfe Castle area of Dorset. They are modified from the work of De la Harpe and Salter (1862) . See Chandler's publications for modern identifications of similar fossil leaves. Apart from in the Natural History Museum in London, good specimens can be seen at the Bournemouth Natural Science Society's building. They can still be found in the region occasionally; a specimen was found a few years at Canford Heath, west of Bournemouth. Old clay pits are worth exploring and cliff sections which may contain leaves exist at Alum Bay and Studland Bay.

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Leaf in pipe clay

Eocene flora - fig leaves etc

Eocene flora - leaves and pods

These beds were examined and described by Gardner in the late 19th Century, and a number of leaves of sub-tropical plants were obtained, also many net-veined ferns [see illustrations]. The main genera represented were Acacia (thorny shrup -source of gum arabic - note that the gum residue known as succinate occurs in the Bournemouth cliffs according to Ord, 1914), Smilax, Lygodium, Myrica, Eucalyptus (the gum tree now confined to the Australian region), and Araucaria (relatives of the Monkey Puzzle and Norfolk Island Pine). There are large collections in the Natural History Museum at South Kensington (see the work of Chandler for later descriptions). The collections are of special importance because, as Ord noted by 1914, these leaves were rarely met with by that date; the lenticular masses of clay from which collections were formerly made have long since fallen from the cliff and disappeared. The clay that was exposed in 1914 does not contain the same remains, but few fossils could be obtained then from this section of the cliff. At the present time the cliffs are greatly obscured by a promenade, sea-defence works and vegetation.

Aralia leaf reconstruction

In his description of the beds between Poole Harbour and Boscombe Pier, Gardner published a diagram showing the position of the more important clay lenses, and the cliff-section above is based on later versions of this. From the west, the first important bed occurred near Canford Chine, where Lygodium and Laurel, together with Hornbeam and Willow leaves, were found. (The illustration here is of a leaf of a herb common in the region - Aralia of the gingseng "five-finger" family. The specimen is from Alum Bay.)

Proceeding from here to near Branksome Chine, Gardner recorded a dark bed of clay almost full of leaves massed together. Ord in 1914 was unable during the previous two years to trace any of these beds. About one hundred metres east of Branksome Chine, though, he found masses of friable yellow sandstone containing numbers of beautiful leaf impressions, amongst which were oak and willow. They were so well preserved that several circular holes which had been eaten out by insects could clearly be seen. These specimens were on display in the Museum of the Bournemouth Natural Science Society. For half a mile from this point no leaves have usually been found, but in a mass of carbonaceous sand near the beach level trunks of several coniferous trees was exposed, the wood being extensively bored by Teredo.

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LOCATION:

Branksome Chine

Silicified tree remains from the basal Purbeck Formation found amongst rock armour from Portland and Purbeck strata at Branksome Chine, Poole, Dorset, 2009

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LOCATION:

LOCATION-Branksome Dene Chine

Geological cliff section from the Zigzag, west of Bournemouth Pier to Branksome Dene Chine, Bournemouth, Dorset

Two units of the Eocene Branksome Sands at Branksome Dene Chine, west of Bournemouth, Dorset

Laminated, lignitic clay and sand in a channel plug at Branksome Dene Chine, Bournemouth, Dorset

The east side of Branksome Dene Chine provides a reasonable section of part of the Branksome Sands. In the lower part of the cliff there is a grey laminated bed, a type of leaf bed, developed at the margin of a channel. It consists of argillaceous silty sand and silty, sandy clay. There are alternating laminae of sand and clay. This is fluviatile unit C of Plint (1988).

A coarse sandstone or granule bed with small pebbles in the Branksome Sand Formation at Branksome Dene Chine, Bournemouth, Dorset

Higher in the cliff is a fluviatile sand and sandstone on yellow and brownish colour with very little clay. A bed near the base is very coarse with particles of granule size or larger. These are mostly of vein quartz and are subangular. There are some darker clasts which may be of tourmalinised slate or tourmaline (the typical material of the Eocene fluvial deposits in the Dorset area is derived from southwest England). The sequence in the upper part of the cliff belongs to fluviatile unit D of Plint (1988). It is a fining-upwards sequence. In the top of the cliff is Pleistocene gravel.

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LOCATION:

Alum Chine and Canford Cliff Chine
(with pyrite industry at Alum Chine and Boscombe Chine)

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Norden's map of 1595 showing the location of copperas houses at Alum Chine and Boscombe (Bascoombe), Bournemouth, Dorset, slightly modified for clarity

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Please go to Brownsea Island - Copperas, Melanterite for more information on production of copperas in this region in historic times.

The Bournemouth beaches, including those of Alum Chine have been extensively renourished with dredged sand. This in addition to sea defences and promenade means that there is little indication there now as to what was the original appearance of the beach.

Ord in 1914 reported that near Alum Chine hard masses of ferruginous sandstone could be seen at low water on the beach, extending for some distance eastward, being one of the few examples of any hard stone occurring in this section of the beds. Although the name "Alum Chine" suggests that pyrite was found there, a reliable geological record places occurrences further west, at the top of the Parkstone Clay Member of the Poole Formation. It is not impossible, though, that significant quantities of pyrite was present near the existing Alum Chine. Gardner (1882) recorded pyrite shore occurrences east of Sugar Loaf Chine and at at Watering Chine (or Branksome Glen Chine). Not far away, offshore at Poole Rocks there is a major deveopment of pyrite pipes.

There is an important leaf bed, the Willow Bed, in the Branksome Sand Formation, to the east of Canford Cliff Chine (also known as Sugar Loaf Chine), and 100 yards east of Branksome Watch Tower. The leaf bed was referred to as a stratigraphical marker. Stratigraphically beneath it there is a major occurrence of pyrite in the strata, almost certainly in the underlying Parkstone Clay Member of the Poole Formation.

Sea water was not far away during deposition of the Eocene strata of the Poole Delta and the Bracklesham open sea was to the east. Thus sulphate was probably readily available and able to be in contact with decomposing plant debris. Such a combination was ideal for the formation of pyrite. It is widespread in the Poole Formation, particularly the Parkstone Clay The seaward part of the Eocene Poole Delta was coincidentally actually in the general region of the present entrance to Poole Harbour (Branksome, Studland, Parkstone, Poole Rocks etc). Here the pyrite development was at its maximum.

Gardner (1882) reported in relation to Sugar Loaf or Canford Cliff Chine (on page 7) as follows:

"Under the leaf-bed just described five reefs of pyrite are visible at low water, running south-east with a WSW dip [this is almost opposite to the regional dip, but local depositional dips are common in the Branksome Sand Formation]. These are succeeded by dark clay dipping E. [expected direction], at about 1 in 50, in which I observed a palm trunk in situ and numerous spines, and a bed of hard lignite, from 6 inches to a foot thick, underlain by brown clay with roots [a palaeosol] and covered by pyrites. Rocks of pyrites again occur opposite Watering Chine [Branksome Glen Chine, west of Branksome Chine], although they are never quite uncovered by the sea; and by means of a diver I was able to trace them two miles seaward towards Alum Bay."[i.e. almost to south of Bournemouth Pier, and therefore passing south of Alum Chine. Note the intentional reference to Alum Bay; pyrite was collected there from strata of similar age for alum production].

Now at Canford Cliff Chine (Sugar Loaf Chine) the top of the Parkstone Clay Member descends with easterly dip under the beach. This then is exactly the same horizon as the pyrite bed on Brownsea Island, only 4km. to the southwest, notable for the historic copperas workings. Although the local dip is anomalous, the regional dip is consistent. Thus it is quite clear that Gardner was following the offshore outcrop of the top of the Parkstone Clay Member. The outcrops at Canford Cliff Chine and on the south side of Brownsea Island are of the exactly the same bed! Alum Chine, is stratigraphically well above the Parkstone Clay pyrite bed, but pyrite could occur there in the Branksome Sand Formation (or the chine might be wrongly named and the real "Alum Chine" is Canford Cliff Chine).

It is worth noting that in Overton's map of 1600 there is indicated "Allom Chine Copperas House" and "Bascombe Copperas House" (ie. at Boscombe) (Riddle (1934) so copperas working was not confined to the Parkstone Clay outcrop or shore exposures. Presumably pyrite could be obtained from the Boscombe Sand Formation, as is supported by the presence of the acid springs.

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LOCATIONS:

Durley Chine

At Durley Chine there have been occasionally found small masses of a hard dark grit known locally as 'Durley Rock.' It is composed of pyritised vegetable debris with carbonaceous sand. In Durley Chine masses of quartz grit cemented by iron are seen a little distance up the Chine. They form a continuous bed which extends, as far as can be traced, for some hundred yards inland. This gives the strike of the beds as roughly north-northeast (Ord, 1914).

By far the most interesting cliff-section palaeontologically is that from Durley Chine to the Pier. Here Gardner obtained many net-veined ferns, especially Gleichenia, also Aroids and a Eucalyptus. A great rarity found farther west was a fossil feather . Palm fronds have frequently been met with, and a magnificent specimen on a slab nearly three feet square is in the Natural History Museum, at South Kensington, London (Ord, 1914).

The conditions under which these strata were laid down are interesting. The deposits are of fluviatile or deltaic origin, and must have been formed in the bed of a great river coming from the west. The quartz sand, which forms the bulk of the cliffs and is of very pure, and together with the white china clay, has been considered to have originated in a granite country (Ord, 1914). Gardner thought that the Bovey Tracey Lignite Beds (now regarded as Oligocene) and the ball clays of Devon were laid down contemporaneously by the same river. He considered that the granites of Dartmoor, Cornwall, and probably an extent of land which has long since been eroded away or submerged in the Atlantic, supplied by its decomposition the quartz sand grains and the china clays. Somewhat similar clays are now worked extensively in the granite regions of Devon and Cornwall, but these are dominantly kaolinite clays, whereas the ballclays and pipeclays of the Bournemouth area are usually kaolinite and illite (and more plastic).

According to Ord (1914) the delicacy of the beautifully preserved leaves in the lenticular clay beds shows that these must have been deposited under tranquil conditions in shallow ponds and lagoons by the sides of the main stream. Through these a gentle stream of clay-hearing water continuously flowed, while the leaves were borne down by the stream or blown in from trees in the vicinity. Now and again the river would overflow its banks and temporarily swamp these side waters, covering them up with layers of sand and coarser material. From the thickness of the beds it is evident that the land was slowly sinking, so that the river channel probably remained at the same level for long periods. Together with the leaves, trunks of trees and water-logged masses of wood floated about; these were attacked by the Teredo shipworm and rapidly bored through and through. This shows that there were some marine incursions into the swamps of the delta. Occasionally there are sand casts of these borings imbedded in a matrix of sand or mud, the woody material having entirely perished, leaving only a dark discoloration where it formerly existed.

At Bournemouth Pier, incidently, traces of a much younger forest which could formerly be seen. The submerged forest, like many in the region (compare with Hayling Island submerged forest) was probably Neolithic in age Ord (1914). It was uncovered at low tides, stumps of coniferous trees being exposed abundantly, in their original sites.

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LOCATION:

Bournemouth Pier to Boscombe Pier (East Cliff etc)

Introduction

Geology of the East Cliff, Bournemouth, Dorset - diagram

A channel fill in the Branksome Sand Formation, between Bournemouth and Boscombe Piers, Dorset, 4th July, 2008

East Cliff, Bournemouth, Dorset, view from pier

Branksome Sand just west of Boscombe Pier, June, 2002

A view of an exposure in the lower part of the cliffs behind the wall, just west of Boscombe Pier, shows some conspicuously laminated beds of clayey silt and very fine-grained sand, the Branksome Sand (Bristow, Freshney and Penn, 1991, p. 62). There are some fine, brown clay layers and much fine-grained lignitic debris. This dark lignitic material marks out partings. Notice the wedge-bedding, a form of cross-bedding on a large scale. The uppermost part of these laminated beds is brown and ferruginous. Above Plint's T4 transgression surface (a major break in sedimentation according to Plint) comes the creamy-white Boscombe Sands which are medium-grained and lack the conspicuous lamination. The laminated sediments, the upper part of the Branksome Sand, belong to the Bournemouth Marine Beds on an older classification, and near here impressions of oysters (with bryozoa) have been found (Ord, 1914).

East Cliff near the Lift, pre-1914

This old view of the cliffs before the promenade was constructed shows the excellent exposures which once existed and the natural supply of sand from the Eocene strata to the beach. At the top of the cliff there is a well-defined bed of Pleistocene Plateau Gravel (Boyn Hill Terrace of Green, 1946 or Terrace 10 of Bristow et al., 1991), formed in periglacial conditions. It is between 0.91m (3 feet). and 2.44m (8 feet) in thickness and rests on an eroded surface of Boscombe Sand (Ord, 1914, Bristow et al., 1991). A thin deposit of blown sand above the gravel is the result of wind action on the cliff raising sand onto the cliff top. This happens at the present time at Hengistbury Head, where even gravel is blown upwards.

As Ord (1914) commented, from Bournemouth Pier the cliffs rise gradually to the east averaging a height of 24m (80 feet) to 27m (90 feet), unbroken by any chine or valley until Boscombe Pier is reached. Between the Zizag and a point 200m east of the lift there are remains of marine molluscs (Ostrea, Arca, Modiola, Tellina, Natica and "Cerithium") and traces of a shore crab. These are in the 'Bournemouth Marine Beds' which are now classified as the uppermost part of the Branksome Sand. Teredo-bored wood occurs in the same area. There are clay lenses with leaves of Podocarpus(Podocarp tree), Lygodium, Hewardia and remains of some unidentified flowering plants (preserved at the Bournemouth Natural Science Society). Ferns, including Polypodium and Osmundia, have been found in the Bournemouth Freshwater Beds (lower part of Branksome Sand and the Poole Formation of Bristow et al., 1991). Some 200m east of the lift at the foot of the cliff some dark-grey, pyritic clay yielded many specimens of a fan-palm, probably a Sabal (Ord, 1914) a genus also found at Studland (Lyell, 1871). Nearby a 3m thick sand bed was seen to contain numerous irregular large mud-clasts ("irregular masses of brown clay"), presumably derived from the erosion of a river bank. Near this in white sand were rolled, thin, clay flakes that had preserved the impressions of leaves with good venation (Ord, 1914).

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LOCATION: Bournemouth Pier to Boscombe Pier

Branksome Sand Formation:

River Channel Plugs of the Poole Delta

Part of channel plug of the Poole Delta in the upper part of the Branksome Sands, East Cliff, Bournemouth, Dorset, 8th March 2014

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Common features of the Branksome Sands, especially the upper part, just the Boscombe Sands, are channel plugs. These are the laminated, sandy clay infills of the channels on the Poole Delta. This is late in its history and it was becoming inudated by the sea from time to time. The part of the delta in the Bournemouth cliffs was behind the beaches in late Bracklesham times. It was not until early Bartonian times that the pebbles of the great storm beaches were driven over it in a westward direction. These delta channels were generally foul and stagnant, causing deposition of pyrite. At times though, marine water entered and occasional marine shells and sharks teeth have been found in them. There are even Teredina borings so palaeosalinity was then suitable for marine life. Sometimes, though the channels were abandoned and ended with aquatic plants living in their swampy environments. See Plint (1983b), Gardner (1987b) and Bristow et al. (1991).

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LOCATION:

Bournemouth Pier to Boscombe Pier

Sulphide Oxidation in the Branksome Sands

Jarosite on the surface of a pyritic bed, Branksome Sand Formation, East Cliff, Bournemouth

In the lower part of the cliffs to the east of the East Cliff Lift some yellow or dirty white efflorescences of sulphate minerals are noticeable. These have resulted from the effects of sulphuric acid which was derived from the oxidation and leaching of pyrite in the clays. Although probably less conspicuous now, some is still visible above the promenade, as shown in the photograph above. In particular, the bright yellow mineral jarosite is a sulphate weathering product, often mistaken for sulphur. It is common on pyritic parts of the cliffs of Dorset and Hampshire (and has been found on Mars!). There is often some association with limonite or goethite which is hydrated ferric oxide derived from the oxidation of the ferrous sulphide. The white or greenish melanterite, (hydrated ferrous sulphate) has also been recorded here (Ord, 1914 ). It is associated with a gummy resinous relic of the vegetation of the Eocene and this is known as succinate. Alum Chine, further west, takes its name from the sulphates present on the cliff. The melanterite, formerly known as "copperas" (there is probably no copper within the sulphate, though) or "alum" was used by tanners, dyers and ink manufacturers, the working of these being an early Bournemouth industry (King, 1974). It was also worked on Brownsea Island and the source pyrite can still be found on the beach there.

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LOCATION:

Bournemouth Pier to Boscombe Pier

Chalybeate Springs (Ochre Springs) and Boscombe Spa

A concentrated variety of Boscombe Spa Water emerged from the cliffs at Toft Zigzag west of Boscombe Pier, Dorset, 4th July 2008

The Toft Zigzag Chalybeate Spring at the path down the cliff near Boscombe, Bournemouth, Dorset, in good condition after heavy rain in early 2014

The quantity of pyrite in the Branksome Sand Formation has produced not only precipitated mineral encrustations, but also brown flowing springs (ochre springs) with ferrous sulphate concentrations. These are chalybeate springs, and are similar to those which have been in use in places such as Tunbridge Wells since the 17th century for medical purposes (supposedly for stomach complaints, constipation, tape worms and skin infections etc). They are common in the Bournemouth area and on the Isle of Wight. The most notable in the region is the Irons Well near Fritham in the New Forest (on Eocene strata of similar age). Shown above is seepage of ferrous sulphate solutions from pyritic, argillaceous sands in the Branksome Sand Formation of the cliffs to the west of Boscombe Pier, at the Zigzag. This seepage is like that which came from the same formation at Boscombe Chine and was used as a spa.

The Boscombe Spa was a ferruginous (chalybeate) spring near Boscombe Chine and Boscombe Spa Road. Physicians recommended their patients to drink the waters for their mineral content, which were said to contain properties similar to those of the Harrogate water (Edwards, 1981, p. 55, et. seq.). Sir Henry Drummond Wolff erected a small, thatched building around the spring, but this was destroyed in 1923. The water was also sold, bottled, as aerated table water and its taste was said to be similar to Seltzer's water, an effervescent mineral water that was considered a fashionable drink. Perhaps, dilution and carbonation rendered the natural brown, rather acid fluid, more agreeable!

See below, for information on the Southbourne Chalbeate Spring.

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LOCATIONS:

Bournemouth Pier to Boscombe Pier

Soft Sediment Deformation in the Branksome Sand Formation
("Bournemouth Marine Beds")

(Probable effects of an earthquake during the Tertiary phase of the English Channel Inversion Structure)

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Location and Introduction

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Eocene uplift of the Inversion Structure - soft sediment deformation (palaeoseismicity?) and a pebble beach development, with Maastrichtian pebbles from the south; evidence from Bournemouth, Dorset, in a cliff section

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The location of soft sediment deformation structures in a sand body within the Branksome Sand Formation, Bournemouth, Dorset

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A broader view of the location of the soft-sediment deformation structures, Branksome Sand Formation, East Cliff, Bournemouth, Dorset, as seen at low tide in February 2004

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Penecontemporaneous erosion of sandstones showing soft sediment deformation, Branksome Sand Formation, East Cliff, Bournemouth, Dorset, 13th February 2014

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The location of very interesting sedimentary structures in the Branksome Sand Formation of East Cliff, Bournemouth, is a short distance east of the Cliff Lift. I hope that this exposure will be conserved and not built over.

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Details

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Soft sediment deformation structures, including pillar and flame, in the Branksome Sand Formatin, Bracklesham, Eocene, East Cliff, Bournemouth, Dorset, 13th February 2014, original photograph, without alteration or emphasis

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Soft sediment deformation structures, including pillar and flame, in the Branksome Sand Formation, Bracklesham, Eocene, East Cliff, Bournemouth, Dorset, 13th February 2014, structures emphasised

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Soft-sediment deformation, an isolated flame structure, Branksome Sand Formation, Bournemouth, Dorset, 13th February 2014

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A recumbent anticline, one of the soft-sediment deformation structures in the high Branksome Sand Formation (Bournemouth Marine Beds, East Cliff, Bournemouth, Dorset, photographed in 2004

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There are some very interesting, soft-sediment sedimentary structures in the Branksome Sand Formation (Bracklesham Group) and quite conspicuous in the Bournemouth cliffs. The structures are present in Bournemouth East Cliff, west of Tosh Zigzag, and east of the cliff lift.

These structures are similar to those described by Kundu et al. (2011), Palaeoseismicity in relation to basin tectonics as revealed by soft-sediment deformation structures of the Lower Triassic Panchet Formation, Raniganj Basin (Damodar Valley), Eastern India. Those soft sediment deformation structures were attributed to the action of earthquakes. There is good reason to ascribe the Bournemouth examples to palaeoseismicity too, because of the sedimentological and palaeogeographic studies of Plint (several papers) and the coincidence of date of occurrence of these structures to initial Tertiary tectonism, both in the Isle of Purbeck and the Isle of Wight (See papers of Daley and others). [This section will be expanded]

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Unusual soft-sediment deformation structures in a sand body of the Branksome Sand Formation, East Cliff, Bournemouth, Dorset

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A possible water escape, burst-through structure, high Branksome Sand Formation, East of Toft Zigzag, East Cliff, Bournemouth, Dorset, 8th March 2014

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Penecontemporaneous contortions in the Boscombe Sand Formation, East Cliff, Bournemouth, Dorset, with at least one possible water-escape structure

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Shown above are early sedimentary structures in sand bodies of the hot and humid Poole Delta, during its later stages. Penecontemporanous, sedimentary sand structures, like this, are common in the top Branksome Sand Formation. They occur again in the Lower Barton Clay Formation at Hengistbury Head and at Friars Cliff, near Highcliffe. More examples are shown below, in older photographs.

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The exposures of slumped  Branksome Sand Formation, near the East Cliff Lift, Bournemouth

Liquifaction or slumping and channeling in the Branksome Sand Formation, East Cliff, Bournemouth

Closer view of liquifaction or slumping in the Branksome Sand Formation , East Cliff, Bournemouth

Slumped sandstone with truncated top, Branksome  Sand Formation, East Cliff, Bournemouth

Just east of the East Cliff Lift there are well-developed liquifaction or slump structures in friable sandstones of the Branksome Sand Formation (Bournemouth Marine Beds). Channels have been cut and these are usually filled with carbonaceous, laminated sandy clays of a chocolate-brown colour. They seem to show some rhythmicity. Lignite is often present in these beds and in some cases they may be representives of the leaf beds in which the interesting and important Bournemouth Eocene flora has been found. This unit, was previously known as the 'Bournemouth Marine Beds' because of the limited assemblage of marine molluscs which have been found. Plint regarded this as his sedimentological unit G, and the British Geological Survey included these strata within the Branksome Sands, as the topmost part.

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LOCATIONS:

Bournemouth Pier to Boscombe Pier

A Small Cliff Fall of Sandstone

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Original State of the Cliff (2004)

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An old photograph of 2004, showing the original form of the cliff at the site of the fall of Boscombe Sands on the night of the 20th to 21st February 2014, between the Zizag Path and the Cliff Lift, east of Bournemouth Pier, Dorset

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The cliff location, as seen from the low tide mark in 2004, of the landslide site of 2014, East Cliff, Bournemouth, Dorset

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The cliff location, as seen from the low tide mark in 2004, of the landslide site of 2014, East Cliff, Bournemouth, Dorset, labelled version

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After the Cliff Fall (2014)

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Two landslide sites in the Tertiary sandstone cliffs of Bournemouth, Dorset, as seen to the northeast of  Bournemouth Pier, photograph 8th March 2014

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Two landslide sites in the Boscombe Sand Formation above the Branksome Sand Formation, Bournemouth, Dorset

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A vertical view of the small, steep landslide site  where Boscombe Sand material fell over Branksome Sand Formation, east of Bournemouth Pier, Dorset, photograph 8th March 2014

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Go to Google Earth - "Bournemouth" - to find the location on an aerial photograph.

[LOCATION IMAGE - GOOGLE EARTH AERIAL PHOTO OFFLINE:
C:\USERS\Desktop\Ian\MY PICTURES-MAIN/AA-JPG-NEW-2014-Comp/JPG-BOURNEMOUTH-OFFLINE/14BMT-A-OFFLINE-Bournemouth-Landslide-Site-GE.jpg]

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As can be seen here, this landslide had a steep, concave slip-plane, that was relatively shallow in relation to the previous cliff surface. The slipping was mostly in the Boscombe Sand Formation, which is higher in the cliff, and overlies part of the Branksome Sand Formation. The Pleistocene Plateau Gravel was only involved to a limited extent. Thus the fallen debris was mostly sand and sandy clay of a grey colour. A certain amount of vegetation such as gorse bushes fell with the stratal debris. Because the cliff is about 35 metres in height and most of the fall was from above 10 metres above the promenade and road, the debris fell fast. There was no obstruction. This is why at road level it showed sturzstrom-like features and moved seaward at high velocity and with a turbulent cloud of suspended material. Apparently at the time, near midnight no-one was in the danger zone. If the fall had happened in daytime there would have been risk of at least serious injury to anyone who was unfortunate enough to be in its (limited) path. Most walkers, though, would have been on the beach side of the road. There would not have been any warning of the fall.

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The cliff section of Eocene strata at Bournemouth Pier and a short distance to the East

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There was a relatively small but very fast, sandstone (weak sandstone or sand) fall from the Bournemouth cliffs at night in early 2014. A 20-metre wide strip of poorly-cemented, sand cliff face fell onto the promenade and beach access road at around midnight on the 20th to 21st February 2014. The upper part of the cliff consists of Boscombe Sands Formation (Bartonian age), the lower part Branksome Sand Formation (Bracklesham Group), with Pleistocene gravel of Gravel Terrace 10 of the British Geological Survey above. The cliff here is about 35 metres in height.

Towards the top of the cliff, in the Branksome Sand Formation there is some ferruginous sandstone. This iron-cemented sand is more resistant and which probably is the cause of part of the upper cliff projecting to some extent at this locality. The band of ferruginous sandstone here is probably that shown in a photograph (Plate 14, opposite p. 316) of Ord (1914).

An usual aspect of the small landslide at the Bournemouth cliffs was a fast run-out (a tongue of debris) onto the promenade. Sand debris, some of it in turbulent, cloudy suspension, seemed to travel at fairly high velocity across the promenade to the beach. This was seen in a film of the event from a CCTV camera of the council, and shown in part on television. It showed that at the bottom of the landslide there some characteristics resembling those of a very small-scale "sturzstrom". This is a type of landslide, with a run-out at the base, with particles held in suspension, largely in air, by particle-to-particle impacts. The material flows outward horizontally at the base like a cloud of debris.

[For more this topic see:
Williams, R.B.G. et al. 2004. A Strurzstrom-like cliff fall on the Chalk coast of Sussex, UK. Pp 89-97 in Mortimore, R.N. and Duperret, A. (Eds.), 2004. Coastal Chalk Cliff Instability. Geological Society of London, Engineering Geology Special Publications, No. 20.]

There were bushes and vegetable debris present in the Bournemouth cliff run-out. The rapidity of the fall and the run-out are also reminiscent of the dangerous falls of sandstone cliff at Burton Cliff, Burton Bradstock, Dorset. They, however, are in vertical cliffs, with hard rock and are very dangerous.

An avalanche type landslide, i.e. one with long run-out, has been reported previously from the Bournemouth Cliffs. Gardner (1879) discussed the notable, but now destroyed (by development), Honeycomb Chine, a short distance east of Boscombe Pier. It was at a place where there are now flats, and not far from the new "surf reef". The chine was notable not only for its scenery but also for the occurrence there of fruits of Nipa, the Vietnam Swamp Palm. These are Gardner's comments:

"120 yards beyond this are the Honeycomb Chines, the sides of which are upward of 100 feet high and of most picturesque occurrence. The ridge separating them, deprived of its gravel capping, and formed of snow-white sand [Boscombe Sand Formation], looks quite Alpine with its sharply cut peaks and water-worn gullies, which may be magnified by imagination into chasms and crevasses. The ribbon-like and netted surface, produced by weathering, produces a singular and striking effect. Lyell represented 3 chines at about the same spot; but it is hardly conceivable that any trace of those should remain at this day, as over fifty years have elapsed. Last spring the face of the buttress separating the two fell away like an avalanche, which will take many a rough sea to remove."

An avalanche-like run-out is characteristic of sturzstrom-type rock falls. The comment about sea erosion, indicates that this run-out was substantial. In the past, before the sea wall and promenade was built, and when coast was rapid here, it is quite likely sturstrom-type sand falls might have been common.

The recent small landslide is probably minute in comparison to the Honeycomb Chine fall. It is just a small part of the natural process of degradation of cliffs at Bournemouth and a progressive and slow reduction in slope to an angle of repose. There is not much sandstone and clay exposed now, and the former cliffs are mostly degraded into slopes covered in vegetation. In geological terms the cliff fall has only very slightly increased the amount of exposure of the bedrock. The cliffs are steeper here between the Zizag Path and the Cliff Lift.

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Remains of an older landslide, just to the west of the fall of early 2014; here cement-filled sandbags have been used to try to support the cliff, East Cliff, Bournemouth, Dorset, 8th March 2014

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There are the remains of a previous sand fall a short distance west of the new sandstone fall. The rock wall of Purbeck limestone seems to have been broken through to some extent in a similar landslide. This is shown in a photograph above. Cement-filled sandbags have been used to try to stabilise the lower part of the cliff. Another landslide might occur, sooner or later, between the two existing scars because the cliff is steep and does not have much lateral support now. There is no reason to believe that any cliff fall here would be very large.

For further information see:
Bournemouth Seafront Landslide Caused by Rainfall. News Dorset of the BBC Online. Extract:
Bournemouth seafront manager Chris Saunders is already overseeing the clear-up of 387 beach huts on the borough's coastline, which were damaged or destroyed either by landslips and storms.
He said: "It's not an uncommon occurrence. It's not a huge slip - we've had worse over the years. We had a cliff slip down at Gordon's Corner, at Southbourne, just before Christmas that wasn't quite as big as this but did more damage because it was where some beach huts were. About three or four years ago just the other side of the East Cliff lift we had a substantial cliff slip that went through the back of a building. Knowing we've had the heavy rains, we commissioned a geotechnical expert to come and check the cliffs through but this has slightly beaten us to it."

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LOCATIONS:

Bournemouth Pier to Boscombe Pier
[Bourne Bottom to Bass Coombe of 17th C]

The Beach

Upward Movement of Piles in Groynes

A distorted groyne, with rising piles, between Bournemouth Pier and Boscombe Pier, Dorset, 4th July 2008

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LOCATIONS:

Boscombe Pier and the Artificial Surf Reef

Boscombe Pier, a popular area for surfing, east of Bournemouth, Dorset, as seen, looking east, from the west side of the pier on January 26th 2009

Boscombe Pier, Bournemouth, Dorset, 6th July 2008, with strong winds and large waves

Boscombe Pier provides a good view of the Bournemouth coast. The west side of the pier is like much of the Bournemouth beach area with an Undercliff Drive, and with a wide replenished beach of sand and pebbles. There is an exposure of the Branksome Sands in the lower part of the cliff, as discussed above.

A short urban stretch of coast with new flats under construction east of Boscombe Pier, Bournemouth, Dorset, 6th July 2008

Approach to Boscombe Pier, Bournemouth, Dorset, 6th July 2008, showing Sea Road and the coast from Boscombe to Hengistbury Head

The east side of the pier is relatively urban and there was even the construction, taking place in 2008, of a large block of flats on the cliff. These flats are now completed. The place is not without interest, though. Although the natural features of the coast here have long been destroyed, the replenished beach contains some interesting pebbles. This sand and pebble deposit here has come from off the Isle of Wight. Most of the pebbles are of subangular flint, but there are many that are of a micritic limestone, probably a hard variety of Chalk. There are occasional bivalve shells present in this. In addition there is some Upper Greensand, and a few other, as yet unidentified rock types. The sand contains many dark grains, possibly of limonitic oolite derived from the Lower Greensand.

Surfers enjoy the pleasures of large waves at Boscombe Pier, Bournemouth, Dorset, 6th July 2008

A miniature stony desert, reg or gibber plain of dredged, replenished sand and gravel at Boscombe, Bournemouth, Dorset, 6th July 2008; this is stock material for the artificial reef

Loss of the stock of dredged sand and shingle, east of Boscombe Pier, Bournemouth, Dorset, 26th January 2009

At one stage sand and gravel, intended for the artificial reef was dumped here. The beach is probably different now, and the situation may be complicated by artificial transport of beach material from east to west by dumper trucks. This is intended to compensate for continual loss of beach sediment by longshore drift towards the east (see recent press report on this topic). However, there has been, at times, much aeolian action and sand blown off the beach, and mostly transported in an easterly direction. As the sand departed the pebbles remained. This is a common feature of deserts showing deflation. This has been seen east of Boscombe Pier in 2008, but may have been a temporary occurrence.

A small sand dune develops against deckchairs near Boscombe Pier,  Bournemouth, Dorset, 6th July 2008, showing eastward transport of sand

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LOCATION:

Boscombe Pier - Artificial Surf Reef - Introduction

The artificial surf reef east of Boscombe Pier, Bournemouth, Dorset, as seen by helicopter on the 6th July 2013.

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Canoes cross the area of the Boscombe Surf Reef, near Boscombe Pier, Bournemouth, Dorset, as seen from a helicopter, 6th July 2013

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In 2008 there was optimism about success of an artificial surf reef at Boscombe; however, later it was damaged, and it was closed in 2011. In 2013, the Director of the firm that built it seems to have gone missing.

Bournemouth Makes Waves with Surf Plan (BBC News, Bournemouth, 19th August 2008. By Gavin Stamp, Business reporter, BBC News, Bournemouth.)
Surfers and swimmers on Boscombe beach.

Bournemouth does not see itself competing directly with Cornwall. ... Soon the town will be hoping to make a few waves of its own as it looks forward to finally welcoming Europe's first artificial surf reef. The plan to build the reef off Boscombe beach, just over a mile east of the town's main seafront, was first mooted nearly a decade ago. Weather permitting, the structure should finally be installed by the end of October... "The weather has not been kind to us," says Jon Weaver, marketing and events manager at Bournemouth Tourism, reflecting on the recent windy conditions which have held up progress on the venture. Praying for calm: All concerned with the 2.6m pound project are hoping for a calm spell to allow the main phase of the complex engineering process - in which layers of matting half the size of a football pitch, with sandbags attached, will be laid on to the sea bed and then secured - to begin. "For laying each section of the reef, we need it perfectly flat," explains construction manager David Neilson. He heads a team of divers, boat crew and pump operators who have come over from his native New Zealand to do the work. Pile of sand on Boscombe beach waiting to be pumped.

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LOCATION:

Boscombe Pier - Artificial Reef - Out of Action - 2011.

Later Press Discussion - 2013

[Extract from BBC report in 2013, after the reef went out of action in 2011.]

Boscombe surf reef director Nick Behunin 'cannot be found'.
Nick Behunin Nick Behunin's New Zealand-based company ASR Limited helped construct the £3.2m reef in 2009. Liquidators for the New Zealand-based company which built Europe's only artificial surf reef are yet to locate its director. ASR Limited, which built Boscombe surf reef in Dorset, was placed into liquidation in September.

Nick Behunin's company oversaw construction of the £3.2m reef which has been out of action since 2011. Bournemouth Borough Council said it registered a claim to be a creditor with liquidators in February. The council is pursuing an insurance claim for damages after two of the reef's sand-filled bags were struck by a boat propeller in May 2011. Liquidators Pricewaterhouse Coopers' six monthly report, released through Companies House in New Zealand, revealed attempts to contact ASR's majority shareholder Sealutions LLC have also been unsuccessful. Since being placed in liquidation, NZ $7,447 (£4,128) has been raised from the sale of the company's remaining assets consisting of two cars, a trailer and various office equipment.

Dan Jenkins, .... said: "It's a real shame. The longer the reef sits idle, the more it will deteriorate... There's a host of local contractors out there who were involved in the original build and could easily undertake the repairs needed."
The reef, made of 55 giant sand-filled bags 740ft (225m) out at sea, opened in November 2009 after lengthy delays and running over budget.

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LOCATIONS:

Boscombe Pier to Southbourne

Introduction

This stretch of cliff shows Boscombe Sand over Branksome Sand (Bournemouth Marine Beds), with Plateau Gravel of Pleistocene age at the cliff top (western part is of Boyn Hill Terrace of Green, 1946 or Terrace 10 of Bristow et al., 1991). A mammoth tooth found near Boscombe Pier, is likely to have come from such gravel. It is in the Red House Museum at Christchurch (Lavender, 1985). Honeycombe Chine , a short distance east of Boscombe Pier, is of special interest and is dealt with below separately. The Boscombe Sand originated on a sea shore. It contains irregular layers of white and yellow sands mixed with beds of well-rolled flints. The shingle is banked up as if by waves coming from the east and King (1974) suggested the banks may have been formed offshore, as bars or shoals, and then driven inland as the sea flooded an area to the west.

Ord (1914) commented that in some of the lower beds (Branksome Sands - Bournemouth Marine Beds) there are occasional fruits resembling Petrophiloides, Cucumites and a Hightea (of Bowerbank) which were found by Gardner. Nearer to Southbourne Seqouia (i.e.related to the California Big Tree or Wellingtonia and the California Redwood Tree) has been recorded. In a bed of sand near the same spot an American form of Cactus has been found (Ord, 1914).

Plint (1980; 1982; 1983a; 1983b; 1988) has provided much information on the sedimentology of the strata and further detail. For this area, east of Boscombe Pier, Bristow et al. (1991, p. 62) have described three sections. Possible Ophiomorpha burrows occur in the lower part of some brown lignitic clay at Southbourne.

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LOCATION: Boscombe Pier to Southbourne;

Honeycombe Chine - Nipa Palm Nuts

Honeycombe Chine, Boscombe, Bournemouth, Dorset, with the Nipadites Bed at the base, as seen in 1914

Nipa palm nuts

Nipa fruit, Nipa burtinii, from the swamp palm occurs in the London Clay of the Isle of Sheppey and in the Eocene Bracklesham Group at Honeycombe Chine, Boscombe, Bournemouth, Dorset

Honeycombe Chine was once a small and attractive chine about 200m to the east of Boscombe Pier. It is shown here as it was sometime before 1914. It has been destroyed by coastal development and is now an ugly car park. It was once notable for the interesting remains of nuts of the stemless palm - Nipa (Ord, 1914). This plant is related to coconut palms and to Pandanus, the screw-pine (Lyell, 1871). This plant is abundant in parts of the Mekong Delta in Vietnam and other tropical and subtropical swamps, often associated with mangroves. At the present day Nipa is a plant highly valued by the villagers of coastal areas. It is found in river estuaries, tidal lands near the sea and on the soft muddy banks of small water-ways. It grows best in freshwater environments but can tolerate some level of salinity in modern deltas which may be rather like the ancient Eocene Poole Delta of Bournemouth area (Bamroongrugsa and Kwanjareon, 1998) .

The Nipa nuts occur in clays within the Branksome Sand, the Bournemouth Marine Beds in older terminology, at the foot of Honeycombe Chine. It is a bed of dark reddish sand, about 0.9 (3 feet) thick and situated about 7.m (23 feet) above beach level. The remains are of the Nipadites fruit, and consists of its remains mixed with rounded vegetable pellets and debris, occurring in layers, perhaps washed together by tidal action (Ord, 1914). The casts of the nuts rarely occur either east or west of this point. Elsewhere fruits of Nipadites occur in the (slightly older) Wittering Formation of the Bracklesham Group of Wittering, Bracklesham Bay, Sussex (Curry et al.) and in the London Clay of the Isle of Sheppey. The Bournemouth specimens are mostly of Nipadites parkinsoni . The fruits have germinated and only the hollow pericarp is found, filled with white sand (for more details see Morris, 1912). The Nipadites bed could be traced for a considerable distance eastward although it rapidly became unfossiliferous.

Lyell (1871) commented on Nipa mainly with reference to the occurrence in the London Clay of the Isle of Sheppey, Kent. There the greatest number of fruits occur in the uppermost 15m (50 feet) of the formation and are mostly found on the beach where the sea has washed away the clay. Lyell stated that Nipa is now only found in the Molucca and Philippine islands, and in Bengal. Dr Hooker had apparently observed floating in the branches of the Ganges Delta such numbers of the large nuts of Nipa fructicans that they obstructed the paddle-wheels of the steam-boats.

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LOCATIONS:

Boscombe Pier to Southbourne; An Ancient 'Chesil Beach'

Eocenen pebble beach deposits with Pleistocene gravel above, Fishermans Walk, Bournemouth, Dorset

Old beach gravel of rounded flints east of Boscombe Pier, Dorset

Battered beach pebbles from the Boscombe Sand, east of Boscombe Pier, Dorset

A flint cobble from the Boscombe Sands Cobble Bed, with very well-developed percussion marks from impacts on ancient, Eocene

In the upper part of the cliff, a moderate walk east of Boscombe Pier, there is an interesting bed of very rounded flint pebbles in the Boscombe Sand. These are characterised by the presence of percussion marks, showing that they have been thrown against each other and rolled in the surf of an Eocene storm beach. They resemble some of the largest pebbles of the Chesil Beach in shape, size and markings but are mainly flint and do have any obvious large quantity of exotic material (the Chesil Beach pebbles are mainly of chert, flint and quartzite). No systematic search for unusual material has been made, though. Some of the clasts exceed in size those of the Chesil Beach and the wave action mau have been even more severe.

The overall upward trend in the predominantly deltaic Bracklesham succession at Bournemouth is towards more marine conditions and culminates in the fossiliferous Barton Clay. Here, east of Boscombe Pier we see the remains of a barrier beach subject to significant storm waves. It is very unlikely that the beach had a similar orientation to the present Chesil Beach, because the palaeogeographic maps show that the sea was to the southeast. The Chalk supplied the flint and the storm waves from the southeast battered the clasts on this delta-front barrier.

Incidently, Curry ound Maestrichtian foraminifera in an Eocene flint pebble on this stretch of coast, and that may provide a further indication of the palaeogeography. It has probably been derived from the uplifted English Channel Inversion during Eocene times.

Another feature of interest in the cliffs between Boscombe and Southbourne is the presence of "decomposed" flints. These are flint pebbles which have undergone partial, internal, dissolution and have been reduced to a white amorphous powdery substance that will leave a white mark on cloth (Ord, 1914; King, 1974). The solubility of silica, of which flints are composed, increases at very high and very low pH values, that is in very alkaline or very acid conditions. Either of these conditions could have caused the partial dissolution. The oxidation of pyrite, producing sulphuric acid, is most likely the cause, but the topic has not been researched in detail.

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LOCATIONS:

Southbourne; Chalybeate Spring

The chalybeate (iron) spring at Southbourne (Brownen, 1914; Kingzett, 1884) was discovered during excavations for a sea wall and esplanade and was situated about 3m. below the beach. It had an inky taste and resulted from the action of fresh water on the iron and aluminium in the strata. Its medicinal properties were said to be "of a pronounced and valuable character and would be beneficial in many cases of anaemia". A well was constructed and it was hoped that a successful spa would result (King, 1974 ). Another iron spring was situated at the southern entrance to Boscombe Gardens.

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LOCATIONS:

Southbourne: Coast Erosion

An esplanade was constructed at Southbourne in 1885 and a pier in 1888. An exceptionally ferocious storm on the 28th December, 1900 breached the sea-wall and severely damaged the pier. Houses on the esplanade were subsequently demolished and the pier dismantled in 1907 (Young, 1989). By 1913 the relics of the esplanade were just rocks at the foot of beach and the cliffs had retreated. The coast here is more exposed to southwesterly storms because it has less protection from the Swanage promontory than has the central and western part of the Bournemouth coast, and therefore more coast erosion can be expected.

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Poole Bay - Offshore

Palaeovalleys of Velegrakis et al. 1999 in Poole and Christchurch Bays

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ACKNOWLEDGEMENTS

I am very much obliged to Southampton University for running this website from their server. I very much appreciate family help with background assistance indirectly benefitting this particular webpage. I come from Bournemouth and have received family help with the coast of this area since the 1940s (it was difficult to visit the beach then; with much barbed wire and anti-tank defences only certain parts were accessible; there was access to short stretches adjacent to the then broken, Bournemouth Pier. Low-flying German planes dropping bombs on Bournemouth only stopped one family outing; it was close, the pilot could be seen.). More recently, Tonya and Joanna are particularly thanked for arranging a helicopter photographic trip and this has been very helpful. Field trips with students on this stretch of coast have been very helpful.

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LINKS: Relevant Websites

Coastal Protection Works at Sandbanks - Borough of Poole. Extracts: "At the beginning of the century, the Sandbanks Peninsula area consisted entirely of sand dunes apart from two coastguard cottages built in 1850 and a few wooden holiday homes. Sandbanks was part of the Wimborne Estates and during the 1910’s, the first plots were sold off and a few permanent homes were built. In post war times, the building of luxury residence with their own waterfront and slipway has escalated with the final infilling of smaller houses, bungalows and blocks of flats. Less than half the dwellings are used throughout the year as permanent residences, the rest are used as holiday flats and second homes. In 1929, the whole of the beach and present recreation ground consisting of 13 acres were purchased from the Estate for the sum of £13." .. "Recent Coastal Protection Work. Phase 1. Due to the increase in the erosion rate and the perceived threat to properties, specialist consultant HR Wallingford was commissioned to produce a design for a coastal protection scheme to deal with the rapidly worsening situation. The scheme chosen built on the partial success of the Midway Path groyne and consisted of four addition rock groynes, one to the west of Midway Path and three to the east. [continues]. [This website is recommended. In case of any difficulty in obtaining it go to the Borough of Poole main website and use the search box. ]

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References and Select Bibliography

See also Bibliography of the Geology of Hengistbury Head webpage.

See also Bibliography of the Geology of Barton-on-Sea and Highcliffe.


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Bamroongrugsa , N. and Kwanjareon, K. 1998. Effects of water salinity on growth of nipa palm seedlings. Internet site: http://wwwclib.psu.ac.th/acad_41/bnop1.htm. Abstract: The experiment was conducted to study the effects of water salinity on growth of nipa palm seedlings (Nypa fruticans Wurmb.) Nipa is a plant highly valued by the villagers of coastal areas. It is found in river estuaries, tidal lands near the sea and on the soft muddy banks of small water ways. Products were obtained from leaves, fruits and sugary sap from fruit or flower stalks. The study was carried out by arranging in groups of young and older seedling. Three levels of salinity were provided for watering the seedlings namely : the fresh water (0 ppt), the brackish water (18 ppt) and the salty water (35 ppt). The results showed that nipa seedlings required fresh water for good growth. The brackish water of 18 ppt caused less growth, while watering with the salty water of 35 ppt resulted in stunted growth and leaf wilting. It was also found that older seedlings appeared to tolerate more to salty water than the younger ones. The results implied that under the natural habitat, different levels of water salinity could control growth and establishment of nipa seedlings.
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Bray , M.J. and Carter, D.J. 1996. Poole Bay and Hengistbury Head. In: Allison, R. (ed) Landforms of East Dorset. Geologists' Association Guide, Geologists' Association, London.
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Bristow , C.R. and Freshney, E.C. 1986. Geology of the Poole - Bournemouth Area. Geological Report for DOE: Land Use Planning. British Geological Survey, Exeter.

Bristow, C.R., Freshney, E.C. and Penn, I.E. 1991. Geology of the Country Around Bournemouth. Memoir for 1:50,000 geological sheet 329 (England and Wales). London, Her Majesty's Stationery Office. 116 pp. ISBN 0-11-884377-X. British Geological Survey. Natural Environment Research Council. (This is the key modern publication to the geology of the Bournemouth area. It is a large paperback, probably still in print and originally sold at £24.75p. It is likely to be available in good local libraries. It is intended for use with the Geological Survey map 329. The emphasis of the publication is on outcrops, lithology and sediments with palaeontological topics covered briefly. It is useful in containing a bibliography of more than 100 references, many of which are not repeated here.)


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Bristow , C.R. and Freshney, E.C. 1986. Geology of the Poole - Bournemouth Area. Geological Report for DOE: Land Use Planning. British Geological Survey, Exeter.

Bristow, C.R., Freshney, E.C. and Penn, I.E. 1991. Geology of the Country Around Bournemouth. Memoir for 1:50,000 geological sheet 329 (England and Wales). London, Her Majesty's Stationery Office. 116 pp. ISBN 0-11-884377-X. British Geological Survey. Natural Environment Research Council. (This is the key modern publication to the geology of the Bournemouth area. It is a large paperback, probably still in print and originally sold at £24.75p. It is likely to be available in good local libraries. It is intended for use with the Geological Survey map 329. The emphasis of the publication is on outcrops, lithology and sediments with palaeontological topics covered briefly. It is useful in containing a bibliography of more than 100 references, many of which are not repeated here.)

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Brownen , G. 1914. Chalybeate spas of Bournemouth cliffs. Proceedings of the Bournemouth Natural Science Society, vol. 5.
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Burnett , D. 1982. Dorset Before the Camera, 1539-1855. Dovecote Press, Stanbridge, Wimborne, Dorset. 134 illustrations. ISBN 0 9503518 7 3. By David Burnett.
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Bury, H. 1916. The physical geography of Bournemouth. Geological Magazine, 53, 133-134. By Henry Bury.

Bury, H. 1920a. Chines and cliffs of Bournemouth. Geological Magazine, 57, 71-76.

Bury, H. 1920b. The chines of Bournemouth. Report of the British Association for the Advancement of Science, Bournemouth, 57, 71-76.

Bury, H. 1925. The Bournemouth plateau and its palaeoliths. Proceedings of the Bournemouth Natural Science Society 16, 72-81.

Bury, H. 1933. The Plateau Gravels of the Bournemouth area. Proceedings of the Geologists' Association, 44, 314-335.

Bury, H. 1934. The Geology of Bournemouth and The Isle of Purbeck. pp. 3-8 in: Watson Smith, S. (1934). The Book of Bournemouth; written for the One Hundred and Second Annual Meeting of the British Medical Association held at Bournemouth in July 1934. Published at Bournemouth, 1934. 212 pp., hardcover book.

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Calkin , J.B. and Green, J.F.N. 1949. Palaeoliths and terraces near Bournemouth. Proceedings of the Prehistoric Society, 15, 21-37.

Calkin, J.B. 1968. Ancient Purbeck: an account of the geology of the Isle of Purbeck and its early inhabitants. The Friary Press, Dorchester, 61pp. With 48 illustrations. Paperback booklet. Price 6 shillings. By J. Bernard Calkin, M.A., F.S.A. [With notes and illustrations regarding dinosaur footprints, fossil leaves, Roman mosaics, Purbeck Marble, Kimmeridge oil shale objects etc.]
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Chandler , M.E.J. 1960. Plant remains of the Hengistbury and Barton Beds. Bulletin of the British Museum (Natural History), Geology, 4, 191-238.

Chandler, M.E.J. 1962. The Lower Tertiary Floras of Southern England. 2. Flora of the Pipe-clay Series of Dorset (Lower Bagshot). British Museum (Natural History), London.

Chandler, M.E.J. 1963. The Lower Tertiary Floras of Southern England. 3. Flora of the Bournemouth Beds; the Boscombe and the Highcliff Sands. British Museum (Natural History), London.

Chandler, M.E.J. 1964. The Lower Tertiary Floras of Southern England. 4. A Summary and Survey of Findings in the Light of Recent Botanical Observations. British Museum (Natural History), London.

Chandler, M.E.J. 1978. Supplement to the Lower Tertiary Floras of Southern England, Part 5. 47p. Tertiary Research, Special Paper 4.
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Cochrane, 1970. Poole Bay and Pubeck 300BC -AD1660. Printed by the Friary Press, Longmans Ltd., Dorchester. 9pp. Paperback. By Mr. C. Cochrane of Bournemouth, also the author of: The Lost Roads of Wessex. [This is a good book with much useful detail on the area. It has a short bibliography and some maps, both old and new.]

[Example extract - p.9 - The Borders of Poole Harbour, introductory part.]

"Nowadays, in the 1970s, it would be hard to find a vacant plot of land from the Haven Hotel at Sandbanks, where the car ferry plies its incessant passage to Shell Bay, to Fleets Corner beyond Poole, or inland to Wimborne and Christchurch. Westward there is a slight gap between Lytchett Matravers and Sandford (for the lately vacated Admiralty cordite factory at Holton has not yet been turned over to building), but from Sandford the new housing estates run through to Wareham and Stoborough.

Only there, and thanks to the Purbeck landlords, can be found recognition of the open heath that still surrounds Corfe Castle and isolates Swanage; and that till lately provided the rather dreary, sometimes foreboding, background to the entirety-ninety-odd miles - of Poole Harbour. Till lately. . . the peninsula of Sandbanks, the North Haven as it was known, must include today some of the most expensive residential property in all England. Sixty years ago the whole spit of land was on offer for (could it be?) a thousand pounds. That is the measure of it.
Across the harbour entrance from Sandbanks, at Shell Bay or South Haven as is its proper name, there remains mile upon mile of untouched heath, a potential klondyke at which many a land speculator must have pursed his lips. The privately-owned toll road, built with the car ferry in the 1920s, runs from the point towards Studland. An unambitious building or two provide teas for summer visitors. A few houseboats nestle out of sight in a harbourside creek. The walker can wander some three miles along the broad sandy coastline to Studland; five miles, finding his way from track to track, to Corfe Castle; or eight to nine or more in a determined ankle-testing foray to Wareham. Away from the beaches he will meet little company other than an occasional farm or forestry worker, or naturalist. For this is a country beloved of botanists and birdwatchers whose rather pompous "keep off" signs are more plentiful than pedestrians."


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Cooper , N.J. and Harlow, D.A. 1998. Beach replenishment: implications for sources and longevity from the results of the Bournemouth schemes. Pp. 162-177 in: Hooke, J. 1998. Coastal Defence and Earth Science Conservation. The Geological Society of London, Burlington House, London. 270 pp. ISBN 1-897799-96-9. Abstract: Beach replenishment is an effective shoreline management tool which can restore immediately coast protection and amenity functions of a beach... Issues concerning sediment sources and replenishment schemes longevity need to be addressed as future scheme use proliferates... From analysis of a long-term beach monitoring record in Poole Bay, southern England, it is suggested that a viable trade-off can be made between tight particle size grading control and the presence of retention structures in the design of effective replenishment schemes... The conservation of sediment resources is essential if replenishment is to be a sustainable option in the longer term.
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Curry, D. 1976. The age of the Hengistbury Beds (Eocene) and its significance for the structure of the area around Christchurch, Dorset. Proceedings of the Geologists' Association, 87 (4), 401-407. Useful paper with fauna. Makes Hengistbury Beds equivalent to Lower Barton on limited evidence. He found a fauna of moulds 13m above the pebble bed and between the two ironstone nodule horizons.

Curry, D., Adams, C.G., Boulter, M.C., Dilley, F.C., Eames, F.E., Funnell, B.M., Wellis, M.K. (1978). A correlation of Tertiary rocks in the British Isles. Geological Society of London, Special Report No. 12, 72pp.

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Daley , B. 1972. Some problems concerning the early Tertiary climate of southern Britain.Palaeogeography, Palaeoclimatology, Palaeoecology, 11, 11-32. By Brian Daley, Portsmouth University, Portsmouth, UK. Author's abstract: Some of the problems of interpreting the Early Tertiary climate of southern England are reviewed. The London Clay flora is not thought to represent a true Tropical Rain Forest climate, but a climatic type not represented at the present day. The climate was seasonal, but frostless; rainfall was higher for the latitude than that of today; temperatures were elevated, though not necessarily as high as those in Tropical Rain Forest areas today. Tropical plants lived near low-lying rivers and lakes, where edaphic moisture supplemented rainfall and where higher atmospheric humidity occurred. If the extra-tropical plants from the London Clay were truely contemporaneous with the tropical forms, it is suggested that they grew further away from these bodies of water under less humid conditions, though not in higher altitudes. During the Oligocene, the climate of southern Britain was comparable to Eastern Margin Warm Temperate conditions of the present day. Its occurrence on the western margin of a continent reflects rainfalll distributed throughout the year, and introduced by a second belt of Westerlies or moisture bearing winds from the Tethys. Arid conditions in the Paris Basin, deduced from Oligocene gypsum deposits, could not have existed contemporaneously with such conditions in southern England. Alternating pluvial and dry climatic periods are therefore inferred.

Daley, B. and Crewdson, P. 1987. 'Bournemouth Cliffs'; a revised cliff profile and an account of the present distribution of the exposures. Tertiary Research, vol. 8, no. 4, 127-132.

Daley, B., Edwards, N. and Insole, A.N. 1979. Lithostratigraphical nomenclature of the English Palaeogene succession. Geological Magazine, 116, 65-66.
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De la Harpe , P. and Salter, J.W. 1862. Notes on the Eocene flora of Alum Bay etc. Pp 109-120 in:Bristow, H.W. 1862. The Geology of the Isle of Wight. Memoirs of the Geological Survey of Great Britain and the Museum of Practical Geology, for Sheet No. 10. Her Majesty's Stationery Office, London, published by Longman, Green, Longman, and Roberts. With a list of fossils revised by R. Etheridge. 138pp with Plates.

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Eaton , G.L. 1971. The use of microplankton in resolving stratigraphical problems in the Eocene of the Isle of Wight. Journal of the Geological Society, London, 127, 281-283.
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Edwards , E. 1981. A History of Bournemouth. The Growth of a Victorian Town. 164pp. Phillimore and Co. Ltd., Shopwyke Hall, Chichester, Sussex. ISBN 0-85033-412-8. [Not geological but an interesting history of Bournemouth with good historic photographs.]

Edwards, R. A. and Freshney, E.C. 1986. Lithostratigraphical classification of the Hampshire Basin Palaeogene deposits (Reading Formation to Headon Formation). Tertiary Research, 8 (2), 43-73.

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Gao , S. and Collins, M.B. 1994. Beach Profile Changes and Offshore Sediment Transport Patterns Along the SCOPAC Coast: Phase 1 Technical Report. Report No. SUDO/TEC/94/95/C. Department of Oceanography, University of Southampton.

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[GARDNER]

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Gardner, J.S. 1879a. On the British Eocenes and their deposition. Proceedings of the Geologists' Association, 6, 83-106. [This is a fairly general paper, commenting on the whole of the Eocene succession and not, therefore, of much significance to the modern reader. It has no abstract.]

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Gardner , J.S. 1879b. Description and correlation of the Bournemouth Beds. Part 1. Upper Marine Series. Quarterly Journal of the Geological Society, London, 35, 209-228. By J. Starkie Gardner. (Read February 20, 1878)
Descriptions of the coast-section between Highcliff and Bournemouth, with which the present paper deals, have already appeared in publications of the Society. That by Sir Charles Lyelll in 1826, was written when the strata included in this section were still supposed to belong to the Plastic Clay [Reading Formation] underlying the London Clay. In it the different beds forming Christchurch Head [Hengistbury Head] are carefully distinguished, and their superposition illustrated in a somewhat idealized section. The description of the eight miles of cliff from a mile beyond White Pits [a site of coastal sand dunes above the Pleistocene gravel, about halfway between Southbourne and Hengistbury Head - shown on old maps] to Poole Harbour is, however, dismissed in a very few words:- The "section presented by the cliffs is continued so precisely in the line of bearing of the strata [the dip], that no new beds rise up, and it is unnecessary to describe them in detail... The prevail character of the strata throughout this extent of coast is fine white sand; but yellowish and pinkish beds of sand occur, and thinly laminated clays in great abundance, resembling in appearance many of the light-coloured argillaceous marls of Montmatre near Paris; but in none could I discover any organic remains except vegetable impressions and these are very indistinct." The proofs of origin, whether marine or freshwater, are considered equivocal. The total thickness of the series, nowhere exposed to view is put down as "not less than 150 feet." It is also suggested that the argillaceous strata with shells of Alum Bay "are probably concealed here at some of the interruptions of the section."
The next description of these cliffs is by Professor Prestwich in 1848, written principally with the view of determining "the exact position which they bear with reference to the Barton Clay" (l.c.p.43) ...
[continues, including important notes regarding an exposure of the Hengistbury Head ironstone nodules in clay at the Run and at Mudeford Spit, thereby countering some correlations of the Hengistbury Beds with the Lower Barton Clay as seen at Highcliffe. See p. 211 et seq.].

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Gardner, J.S. 1879c. On the correlation of the Bournemouth Marine Series with the Bracklesham Beds, the Upper and Middle Bagshot Beds of the London Basin, and the Bovey Tracey Beds. Geological Magazine, 6, 148-154.

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Gardner, J.S. 1880. Excursion to the Hampshire Coast. Proceedings of the Geologists' Association, London, vol. 6, no. 7, July, 1880, pp. 316-320. Journal edited by J. Logan Lobley, F.G.S., University College, London. Price 1s, 6d.

This field report is of some interest particularly with regard to the cliffs of Bournemouth, which were then exposing good plant fossils, and also in relation to Hengistbury Head, Barton and eastwards. It has no diagrams but the text is reproduced in full, below:




EXCURSION TO THE HAMPSHIRE COAST.

EASTER MONDAY, MARCH 29TH, 1880 AND FOLLOWING DAY.

Director :J. STARKIE GARDNER, Esq., F.G.S.
(Report by Mr. GARDNER.)

The head-quarters of the Association were fixed at Bournemouth, and Members not arriving until Monday were indebted to Mr. Swain for procuring rooms, etc. A large number arrived during the previous week, and were able to explore the Fresh-water series to the west of Bournemouth, which could not be visited on the Monday or Tuesday. An excavation opened a few days previously by Professor Morris, Dr. Hy. Woodward, Prof. Corfield and Mr. Birch, yielding fine leaves, was visited by Dr. John Evans, Prof. McKenny Hughes, Mr. Warrington Smyth, Prof. Bonney, and many Members of the Association. .

First Day .- The Members and visitors, between 60 and 70 in number, met together at Bournemouth pier and proceeded along the shore towards Boscombe. On the way the Director pointed out the position of the Bournemouth series in the Eocene formation, and the chief geological features of the coast. Far to the west, and close to Poole harbour, could be seen the cliffs which contain a rich dicotyledonous flora, shed apparently from forest trees which clothed the hilly slopes of the right bank of the Eocene river. This flora, or rather series of floras, differ remarkably from those found nearer towards Bournemouth, especially in the hitherto total absence of remains of palm. The central ranges of cliffs are almost unfossiliferous, and from their confused bedding are conjectured to present a transverse section of the silting up of the old river channel. From the pier for nearly a mile, the eastern series of leaf-beds extends, containing the remains of a very much more tropical-looking flora, probably derived from the low-lying shores of the left bank of the river. Among the palms, which are very abundant, such genera as Phoenix, Calamus, Iriartea, Sabal, etc., are conspicuous, and among the ferns, some scarcely differing from such magnificently tropical forms as 0smunda javanica and Chrysodium aureum, Gleichenia dichotoma, Lygodim dichotomum, etc. Beyond these cliffs, skirting the nearly vertical Chalk downs, are the Lower Bagshot Beds, in which the well-known leaf-beds of Alum and Studland Bays are situated, invisible on Monday through the haze, and beneath these the Lower Tertiaries. Only the upper part of the Bournemouth Fresh-water series which are estimated to be 400 ft. thick, was actually passed on Monday. The broken angulated blocks, imbedded in sand, whence come Aroids and a representative of Araucaria Cunninghami, not met with higher in the series, were pointed out. Within a few hundred yards the Freshwater series, with its white clays, sharp quartzose sands, and entire absence of flint, became replaced by the Marine series. Owing to the absence of any slips, and the consequent inaccessibility of most of the beds, few fossils could be obtained, although indistinct leaf impressions of the reticulated fern-fronds, which immediately underlie the marine beds, were seen. The passage of Marine to Fresh-water beds at this point was pointed out. The marine beds are stiff liver-coloured clays, becoming black on exposure to the air, containing casts of several genera of Bryozoa and Crustacea, and greenish sandy clay with casts of Bracklesham molluscs. They are highly charged with lignitic matter, and contain in places very perfect fruits, and much teredo-bored wood. Overlying them are the clean white sands, with flint shingle-beds of the Boscombe series, and above these are thick capping of angular Quaternary gravel. The Eocene shingle beds consist of perfectly rounded flints, showing the existence, at the time they were deposited, of a heavy surf. In many cases the condition of the silex is changed, and appears a soft, chalk-like mass. Pebbles are met with in every stage of the change, whol1y converted, with black flint nucleus, half converted, or merely with a thickened white coat. The process and nature of the change gave rise to much discussion. The party were here met by Dr. Allman, President of the Linnrean Society, and Mr. Pike, owner of the vast china-clay pits near Corfe Castle. Nearing Boscombe, the positions of the various fruit-beds were pointed out, and the curious tubular borings of annelids fil1ed with horizontally-arranged lignitic matter or with fine sand, which, in places riddle the dark clays. At the corner of Boscombe Chine, instances of the denuding power of wind were seen, and in the extraordinary Honeycombe Chines, that of springs in rapidly excavating deep cirques in the soft strata. The zone of Nipadites was well seen, the empty husks floated out to sea, and now filled with sand, being in places crowded together. At another spot fragments of proteaceous or myricaceous leaves were found.

The party then proceeded somewhat rapidly to Hengistbury Head, a distance of about four miles. On the way it became apparent that, as the Fresh-water beds present a transverse section across a vast river-channel, so the Marine beds present a section through a great Eocene beach or sandbank, behind which lay a stagnant lagoon. The shingle in them became larger and larger towards the east, their well-rolled appearance indicating the distance they had travelled. Attention was called to their resemblance to the so-called Upper Bagshots of the London Basin.

The principal features of the Head-land itself were fully described in the "Quarterly Journal of the Geological Society" for May, 1879, p. 213, and tbe divisions were clearly made out. Having skirted it along the shore, the party mounted to the top over the debris is of the old quarries, and after enjoying the magnificent view, quickly made their way through the heather, past the prebistoric double ramparts and ditch, to the ferry over the Stour and Avon, and thence to Christchurch. Mr. George H. Birch, F.R.S., B.A., who bad travelled from London for the purpose, gave, in the failing light, an able and only too brief sketch of the history of the ancient and striking Priory Church. The Members then returned by rail to Bournemouth, and dined together at the Criterion Restaurant.

Second Day (Tuesday.) - The party proceeded by rail to Christchurch, when the fine Norman house attracted attention, and the church was again examined while waiting for conveyances. The different building stones used were pointed out by Mr. Birch, these included Hengistbury ironstone for the foundations, and Bembridge, Binstead, Headon, Portland, Purbeck and Caen limestones for the edifice. The Members then drove to Mudeford, and thence found their way along the base of the cliffs to Highcliff. The new channel recently created by the Stour and Avon for a mile along the base of these cliffs caused much surprise when the rapidity with which it had been formed became known. The thin Nummulite bed, which is considered by the Rev. O. Fisher to divide the Bracldesham and Barton Series, could not be found in the short time at disposal, owing to the cliff under Highcliff Castle having been sloped and drained. The main features of the coast were, however, pointed out, the sequence of the beds from Hengistbury to Highcliff, the Barton Clays and Sands, the Upper Bagshots and Headon Beds of Hordle. During the short halt for lunch, Prof. Morris favoured a number of the party with an eloquent address, in which he clearly pointed out the sequence and chief characteristics of the beds and their correlation with the Eocenes of Europe, and briefly sketched, in eulogistic terms, the work of those whose labours have made it possible to trace the history of their deposition.

Dr. Henry Woodward and Prof. Bonney and the Director, having also made a few remarks, the party dispersed to collect the well-known Barton shells, which usual1y lay exposed in thousands upon the slopes of the cliffs, and notwithstanding the dryness of the weather being unfavourable, many beautiful specimens of the characteristic shells and teeth were obtained. Beyond Chuton Bunny most of the party again came together. Owing, however, to the shingly character of the beach, and time pressing, a large number soon after chose the coast path, and viewed the Hordle part of the series from above. Lord Justice Thesiger, of Hordle House, wrote to express his regret at being unable to join the excursion. During a short halt, when Dr. Foulerton kindly proposed a vote of thauks to the Director, the magnificent panorama which stretched for 50 miles, embracing the Isle of Wight, the Solent and the whole coast to St. Alban's Head, and the Purbeck Hills, was fully appreciated. The Members soon after entered the conveyances provided for them at Milford, and drove to Lymington. The 5.50 train to London took the party to Brockenhurst, where a number left it to return to Bournemouth. The Excursion, was largely attended, and owing to the magnificent weather and the beauty and interest of the country traversed, was keenly enjoyed. [end of report]




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Gardner, J.S., Keeping, H. and Monckton, H.W. 1888. The Upper Eocene, comprising the Barton and Upper Bagshot Formations. Quarterly Journal of the Geological Society, London, 44, 578-635. [For Barton see particularly pp. 580, 583-4, 587-591, 594, 601, 620-633].

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Gardner, J.S. 1882. Description and correlation of the Bournemouth Beds. Part 2. Lower or Freshwater Series. Quarterly Journal of the Geological Society, London, 38, 1-15. By J. Starkie Gardner. February 1982. About two years ago I had the honour of laying before this Society a description of the marine beds of the Middle Bagshot, exposed between Highcliff and Bournemouth. In continuation of my former paper, I now propose completing the description of the Eocene cliffs of this part of Hampshire, as far as Poole Harbour.
These are of freshwater origin, and chiefly interestingon account of the fossil flora obtained from them. This appears to be the most extensive and varied yet brought to light from the Tertiary formations; and its study, even now, promises to modify the views held as to the age of the very many of the similar fossil floras described from other parts of the world. .... To illustrate the relative importance of the flora of Bournemouth, I may mention that there are 19 species of ferns described from it, and that only 10 have been met with in all the other British Eocenes and Oligocenes, including Bovey Tracey, and three of these are also found at Bournemouth....[continues]

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Gilkes , R. 1968. Clay mineral provinces in the Tertiary sediments of the Hampshire Basin. Clay Minerals, 7, 351-361.

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Goldring , R., Polland, J.E. and Taylor, A.M. 1992. Excursion A4. Sedimentology and ichnology of the shallow marine Barton Group (Eocene) at Hengistbury Head and Barton on Sea. Pp 53-65 in: BSRG 1992, Southampton, Field Excursion Guides, 65 p. Department of Oceanography, Southampton University.

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Green , J.F.N. 1945. The history of the Bourne and its valley. Journal?

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Halcrow , Sir William and Partners, 1980. Poole and Christchurch Bays Research Project, Phase One Report, 2 Volumes. Report to the Department of the Environment.
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Hinchcliffe , J. & Hinchcliffe, V. 1984. Dive Dorset. Underwater World Publications, Area 4 - Offshore Diving, p. 164-5 (extract seen which starts at earlier page unknown and finishes at a later page). Supposed "fossil trees" at Middle Poole Patch, Bournemouth Rocks and Durley Rocks. A Tertiary age is implied. The "trunks" stand up to 5 feet high above the sea-floor. These have subsequently been examined petrographically, by XRD and SEM (by a student of mine) and are, in fact, pipes of pyrite with central cavities. Comparison has been made with the limonitic pipes of Redend Point, Studland, which might have been oxidised pyrite pipes of similar character. (More information will be provided on this subject later).

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King , M.P. 1974. Beneath Your Feet: The Geology and Scenery of Bournemouth. The Purbeck Press, Swanage. 36pp, paperback booklet. By Michael P. King, B.A., County Borough of Bournemouth Education Committee.
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Kingzett , C. 1884. On a chalybeate water and saline deposit from Southbourne-on-sea. Journal?
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Kirkaldy , J.F. 1967. Fossils in Colour. 223pp. Blandford Press, Dorset. [including leaf remains from Alum Bay]


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Kundu, A., Goswami, B., Eriksson, P.G. and Charaborty, A. 2011. Palaeoseismicity in relation to basin tectonics as revealed by soft-sediment deformation structures of the Lower Triassic Panchet Formation, Raniganj Basin (Damodar Valley), eastern India. Journal of Earth Science Systems, Indian Academy of Science, Vol. 120, No.1, February 2011, pp 167-181. Available online. By Abhik Kundu, Bapi Goswami, Patrick G. Eriksson and Abhijit Chakraborty.
Abstract:
The Raniganj basin in the Damodar valley of eastern India is located within the riftogenic Gondwana Master-Basin. The fluvio-lacustrine deposits of the Lower Triassic Panchet formation of the Damodar valley in the study area preserve various soft-sediment deformation structures such as slump folds, convolute laminae, flame structures, dish and pillar structures, sandstone dykes, pseudonodules and syn-sedimentary faults. Although such soft-sediment deformation structures may be formed by various processes, in the present area the association of these structures, their relation to the adjacent sedimentary rocks and the tectonic and depositional setting of the formation suggests that these structures are seismogenic. Movements along the basin margin and the intra-basinal faults and resultant seismicity with moderate magnitude (2 -5 on Richter scale) are thought to have been responsible for the soft sediment deformation.

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Lavender , J. 1985. Land Shape and Geology. Pp. 9-13 in: Pepin, C. 1985. Hengistbury Head. Bournemouth Local Studies Publications, Roman Press Ltd., Bournemouth, 79pp.
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Lyell , C. 1827. On the strata of the Plastic Clay Formation exhibited in the cliffs between Christchurch Head, Hampshire and Studland Bay, Dorsetshire. Transactions of the Geological Society, London, Ser. 2, 2, 279-286.

Lyell, C. 1871. The Student's Elements of Geology. John Murray, Albemarle Street, London, 624pp. By Sir Charles Lyell, Bart. F.R.S., Author of 'The Principles of Geology', 'The Antiquity of Man' etc. With more than 600 illustrations on wood. (Brief references to Bournemouth on pp. 237, 238).

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May , V. 1990. Replenishment of the resort beaches at Bournemouth and Christchurch, England. Journal of Coastal Research, SI (6), 11-15.
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Melville , R.V. and Freshney, E.C. 1982. British Regional Geology: the Hampshire Basin. Institute of Geological Sciences, H.M.S.O., London. (Good introduction to the geology of the region).
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Monckton , H.W. and White, H.J.O. 1910. Hampshire and Bagshot District. Chapter 12, pp. 277-292 in: Monckton, H.W. and Herries, R.S. (Eds.) 1910. Geology in the Field. The Jubilee Volume of the Geologists' Association (1858-1908). Edward Stanford, London. 916 pp. Illustrated by 32 plates and 138 figures in the text. ["The Association has on three occasions visited the cliffs of Bournemouth and Barton, viz., at Easter, 1880, Easter, 1888, and Easter, 1894, and Mr Starkie Gardner, who acted as director, or one of the directors, on these occasions, explained that he did not wholly agree with the classification of strata adopted by the Geological Survey. His views of the relationship of the Hampshire Eocene beds to those of the Isle of Wight are very clearly shown by the diagram ..." continues. It includes fig. 48. View of the cliffs between Poole Harbour and Boscombe, showing position of plant-beds etc., J. Starkie Gardner. In addition to discussion of the Bournemouth cliffs before the promenade was built, and of Hengistbury Head, and of the breaching of Mudeford Spit, there are description of the Barton and Hordle cliff sections.]

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Morris , D. 1912. Nipadites in Eocene beds at Bournemouth. Proceedings of the Bournemouth Natural Science Society, 3, 78-81.

Morris, S. (Steven). 2009 (23rd January 2009). Shifting Sands Swell the Cost of UK's First Artificial Reef. The Guardian Newspaper, Friday 23rd January, 2009.
If all had gone to plan surfers would by now be whizzing into a Bournemouth beach on waves boosted by Britain's first artificial surf reef. Instead, taxpayers face a bill of almost a quarter of a million pounds to stop the project blowing away. The reef at Boscombe, east of the main town of Bournemouth, in Dorset, was due to be completed in the autumn but rain and winds halted the construction. Work is due to resume in April and finish by the summer's end. But the delay has inflated the reef's price and Bournemouth borough council says 169,000 pounds has to be found to replace sand brought in for its construction on the seabed but lost to the elements over the winter [see photographs above]. Flattening the temporary dune to protect it from the wind and tides would cost a further £70,000, says a report due to be seen by the local authority next week. Besides this, £100,000 is reportedly needed to help pay the contractors, ASR. Originally the price of the reef project was estimated at 1.4m pounds. By last summer it was up to 2.7m pounds and, following the winter delay, it is now at the 3m pound mark. It could also cost as much as 100,000 pound a year to maintain the reef, and the cost of the wider regeneration project for Boscombe has also risen, to 11m pounds. Basil Ratcliffe, a Tory councillor, said: "Someone should be given the bullet over this ... these are big sums that could have been spent on something else." The report defends the soaring price, saying the reef is a complex marine structure. A council spokeswoman said: "The council has set aside ... 169,000 pounds but it might not need to buy this much [sand]."

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Ord , W.T. 1910. In: Hovenden, F., Monkton, H.W., Ord, W.T. and Woodward, A.S. Excursion to Swanage, Lulworth Cove and Bournemouth. Report by the Directors. Proceedings of the Geologists' Association, 21, 510-521.

Ord, W.T. (Dr William T. Ord) 1914. Geology. Pp. 303-356 in: Morris, D, 1914. (Editor - Sir Daniel Morris, K.C.M.G, J.P., M.A., D.C.L., D.Sc., F.L.S., F.R.H.S., President of the Bournemouth Natural Science Society). A Natural History of Bournemouth and District; including Archaeology, Topography, Municipal Government, Climate, Education, Fauna, Flora and Geology. By the Members of the Bournemouth Natural Science Society. 400pp. Published by the Natural Science Society. Sold by Horace G. Commin, 100, Old Commercial Road and Bright's Stores Ltd., The Arcade, Bournemouth. [This is an interesting account written when much was still visible in the cliffs and with some good points not discussed much elsewhere.]

Ord, T., Rankin, W.M. and St. Barbe, H. 1914. Topography. In Morris, D. 1914. A Natural History of Bournemouth and District. 400pp. By Dr. William T. Ord, F.G.S., William Munn Rankin, M.Sc., B.Sc. and Henry St. Barbe.

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Pepin , C. 1985. Hengistbury Head. Bournemouth Local Studies Publications, Roman Press Ltd., Bournemouth, 79pp.

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[By Dr. A.G. Plint or Dr. Guy Plint, a Professor at Western University, Ontario, Canada. He completed his D.Phil on the Bournemouth Cliffs in 1980 when he was at Oxford University. His papers are the most informative on the sedimentology of the Eocene Bournemouth cliffs.]

Plint , A.G. 1980. Sedimentary Studies in the Middle Eocene of the Hampshire Basin. Unpublished D.Phil. Thesis, University of Oxford, 3 volumes.

Plint, A.G. 1982. Eocene sedimentation and tectonics in the Hamphire Basin. Journal of the Geological Society of London, 139, 249-254.

Plint, A.G. 1983a. Sandy fluvial point-bar sediments from the Eocene of Dorset, England. Special Publication of the International Association of Sedimentologists, No. 6, 355-368.

Plint, A.G. 1983b. Facies, environments and sedimentary cycles in the Middle Eocene, Bracklesham Formation of the Hampshire Basin: evidence for global sea-level changes? Sedimentology, 30, 625-653.
Abstract:
The Bracklesham Formation is of Middle Eocene age and occurs throughout the Hampshire Basin of southern England. The basin is elongated east-west and filled with Lower Tertiary sediments. Its southern margin is marked by either large, northward-facing monoclines, or faults, both of which underwent differential movement, with uplift of the southern side throughout the Middle Eocene. The Bracklesham Formation, which is up to 240 m thick, shows pronounced lateral facies changes with dominantly marine sediments in the east passing to alluvial sediments in the west. Four principal sedimentary environments: marine, lagoonal, estuarine and alluvial are distinguished. Marine sediments comprise six facies including offshore silty clays and glauconitic silty sands, beach and aeolian dune sands, and flint conglomerates formed on pebble beaches. Offshore sediments predominate in the eastern part of the basin, as far west as Alum Bay, where they are replaced by nearshore sediments. Lagoonal sediments comprise four facies and formed in back-barrier lagoons, coastal marshes and, on occasions, were deposited over much of the basin during periods of low salinity and restricted tidal motion. Five estuarine facies represent tidal channels, channel mouth-bars and abandoned channels. These sediments suggest that much of the Bracklesham Formation was deposited under micro- to meso-tidal conditions. Alluvial sediments dominate the formation to the west of Alum Bay. They comprise coarse to fine sands deposited on the point-bars of meandering rivers, interbedded with thick sequences of laminated interchannel mudstones, deposited in marshes, swamps and lakes. Extensive layers of ball clay were periodically deposited in a lake occupying much of the alluvial basin. In alluvial areas, fault movement exposed Mesozoic rocks along the southern margin of the basin, the erosion of which generated fault-scarp alluvial fan gravels. Locally, pisolitic limestone formed in pools fed by springs emerging at the faulted Chalk-Tertiary contact. In marine areas, flint pebbles were eroded from coastal exposures of chalk and accumulated on pebble beaches and in estuaries. From other evidence it is suggested that older Tertiary sediments were also reworked. The Bracklesham Formation is strongly cyclic and was deposited during five marine transgressions, the effects of which can be recognized throughout the basin in both marine and alluvial areas. Each of the five transgressive cycles is a few tens of metres thick and contains little evidence of intervening major regression. The cycles are thought to represent small-scale eustatic sea-level rises (‘paracycles’) superimposed upon a major transgressive ‘cycle’ that began at the base of the Bracklesham Formation, following a major regression, and was terminated, at the top of the Barton Formation by another major regression. This major cycle can be recognized world-wide and may reflect a period of rapid northward extension of the mid-Atlantic ridge.

Plint, A.G. 1983c. Liquifaction, fluidization and erosional structures associated with bituminous sands of the Bracklesham Formation (Middle Eocene) of Dorset, England. Sedimentology, 30, 525-535. (Carbonaceous rather than bituminous sands?).

Plint, A.G. 1988. Sedimentology of the Eocene strata exposed between Poole Harbour and High Cliff, Dorset, UK. Tertiary Research, 10, 107-145.


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Poole and Christchurch Bays, Shoreline Management Plan - SMP - Key Publications

See these important documents on the plans for the coastal management or shoreline management of the area. Summarised contents of a version are given below and look for the section of interest. However, this SMP is not the final version, and there will be an update. If you do not find it directly from the links here, search by Google etc for the latest version, using the keywords - "Poole Christchurch SMP".

Poole and Christchurch Bays Coastal Management Group. 2010. (SMP - Shoreline Management Plan)
Poole and Christchurch Bays Coastal Management Plan (or SMP - Shoreline Management Plan). Draft SMP2. Draft version of the SMP, later to be replaced by final version (see this when it is available. SMP2 is due to be published in April 2010.). Available online as PDFs at Poole and Christchurch Bays Coastal Management Plan.

Contents: Draft SMP2
Section 1, Introduction
Section 2, Environmental Assessment
Section 3, Basis for Development of the Plan
Section 4, Appraisal of Options and Rationale for Preferred Plan:
Section 4.1, Introduction.
Section 4.2, Policy Development Zone 1 Central and Eastern Sections of Christchurch Bay (Hurst Spit to Friars Cliff).
Section 4.3, Policy Development Zone 2 Christchurch Harbour and Central Poole Bay (Friars Cliff to Flag Head Chine).
Section 4.4, Policy Development Zone 3 Poole Harbour and Associated Coastline (Flag Head Chine to Handfast Point, including Poole Harbour).
Section 4.5, Policy Development Zone 4 Swanage (Handfast Point to Durlston Head).
Section 5, Summary of Preferred Plan and Implications
Section 6, Policy Summary, including Policy Summary Map.
Appendices (all documents open in a new window)
Appendix A, SMP Development.
Appendix B, Stakeholder Engagement.
Appendix C, Baseline Process Understanding, including Coastal Process Report and Flood and Erosion Mapping. Accessible from a separate page including No Active Intervention (NAI) and With Present Management (WPM) assessments, and summaries of the data used in assessments.
Appendix D, Natural and Built Environment Baseline (Thematic Review).
Appendix E, Issues and Objective Evaluation.
Appendix F, Strategic Environmental Assessment.
Appendix G, Scenario Testing.
Appendix H, Economic Appraisal.
Appendix I, Estuary Assessment.
Appendix J, Habitat Regulation Assessment - Appropriate Assessment.
Appendix K, The Metadatabase, GIS and Bibliographic Database is provided to the operating authorities on CD. It will be included in the final SMP.
Appendix L, Water Framework Directive (WFD)
Appendix M, Review of Coastal Processes and Associated Risks at Hengistbury Head.

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Prestwich , J. 1846. On the Tertiary or Supracretaceous Formations of the Isle of Wight, etc. Quarterly Journal of the Geological Society, London, 2, 255-259.

Prestwich, J. 1849. On the position and general character of the strata exhibited in the coast section from Christchurch Harbour to Poole Harbour. Quarterly Journal of the Geological Society, London, 5, 43-49.
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Reid , C. 1898. Geology of the Country round Bournemouth. Memoir of the Geological Survey. Sheet 329 (England and Wales). By Clement Reid.

Reid, C. 1916. Ancient rivers of Bournemouth. Proceedings of the Bournemouth Natural Science Society, 7, 73-82.

Reid, C. and Chandler, M.E.J. 1933. The Flora of the London Clay. British Museum, Natural History, London, 561pp.


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Riddle, C. (Charles). 1934. Bournemouth: an Historical Sketch. Pp. 38-47 in Watson Smith (1934). The Book of Bournemouth. 2010 pp.

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Smith , A.G. and Briden, J.C. 1977. Mesozoic and Cenozoic Paleocontinental Maps. Cambridge Earth Science Series, Cambridge University Press, 63 pp. ISBN 0 521 29117 8 (paperback).
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Stinton , F.C. 1975. Fish otoliths from the English Eocene. Palaeontographical Society (Monograph) : (1), pp.1-56. by Fred Stinton.

Stinton, F.C. and Curry, D. 1979. Lithostratigraphical nomenclature of the English Palaeogene succession. Geological Magazine, 116, 66-67.

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Velegrakis , A.F. 1994. Aspects of the Morphology and Sedimentology of a Transgressional Embayment System: Poole and Christchurch Bays, Southern England. Unpublished Ph.D. Thesis, Department of Oceanography, Southampton University, 319pp.

Velegrakis, A.F., Dix, J.K. and Collins, M.B. 1999. Late Quaternary evolution of the upper reaches of the Solent River, southern England, based on marine geophysical evidence. Journal of the Geological Society, London, vol. 156, pp. 73-87. [This is a key paper with a map showing the offshore buried channels in Poole Bay and Christchurch Bay.]
Abstract: Geological evidence suggests that during the Late Quaternary, a river system (the Solent River) drained a large part of central Southern England. Its upper reaches flowed in a west-east direction, flanked to the south by a Chalk ridge (the Purbeck-Isle of Wight Chalk Ridge). Today, only part of the upper reaches of the river's tributary channels remain, as the area was inundated during the Flandrian Transgression, forming. an embayment system (Poole and Christchurch Bays). In order to map the offshore buried channels of the upper reaches of the Solent River an extensive set of shallow-marine geophysical data was analysed and interpreted. The results of this investigation show that the Solent River system was disrupted irreversibly by southerly capture of its upstream section before the Flandrian Transgression. This disruption was the result of the fluvial breaching of the southern barrier of the system (the Purbeck-Isle of Wight Ridge) at three points, probably during Late Devensian time. Poole Bay was first to be submerged during the transgression. The estuaries which resulted from the drowning of the fluvial palaeovalleys of Poole Bay were infilled with transgressive facies sequences which have been preserved within the buried palaeovalleys. In contrast, Christchurch Bay was submerged at a later time, but because of the abrupt manner of its inundation, no transgressive facies have been preserved within its buried palaeovalleys. [end of abstract]
[Example extract from the introduction] The Isle of Wight, southern England, is separated from the mainland by a stretch of water known as the Solent (Fig. I). The Solent is located at the southern margin of the Hampshire Basin, an elongated asymmetrical downwarp of Tertiary deposits, the southern limb of which exhibits a near-vertical northern dip, whilst the beds on its northern limb slope gently southward (Melville & Freshney 1982). It has been widely proposeq that, during Pleistocene lowstands, the Solent formed a segment of a major axial stream (the 'Solent River'), which integrated all the consequent rivers of the basin (Fox 1862; Reid 1905; Everard 1954; West 1980). It has been suggested that this river constituted one of the principal northern tributaries of the English Channel River, a major river system established over northwestern Europe early in the Middle Pleistocene Epoch (Gibbard 1988). The Solent River flowed along a large W-E-trending valley incised into Tertiary arenaceous and argillaceous sediments and surrounded by high Chalk country (the Wiltshire and North Dorset Downs to the north and the South Dorset Downs and the Purbeck-Wight Chalk Ridge to the south). Much of the catchment area of the river was drowned during the last eustatic sea-level rise. Only parts of the tributary river systems are still intact; these form the modern drainage network of the area (Fig. 2).
Evidence for the existence of the Solent River system is distributed throughout the area. Onshore, extensive deposits of Pleistocene sands and gravels occur, forming terraces along the present river valleys (Keen 1980; Freshney et al. 1985; Allen & Gibbard 1993), and underlying the Flandrian deposits of some of the estuaries of the area (Nicholls 1987). Offshore, marine geophysical surveys have revealed systems of buried river valleys under the present seafloor, incised to a maximum depth of 46 m below OD to the east of the Isle of Wight (Hamblin et al. 1992). [continues for more than 14 pages, with maps and diagrams].

Velegrakis, A.F., Dix, J.K. and Collins, M.B. 2000. Late Pleistocene - Holocene evolution of the upstream section of the Solent River, Southern England. Pp. 97-99 in: Collins, M. and Ansell, K. 2000. Solent Science - A Review. Elsevier, Amsterdam, 385pp. [Using shallow seismic and echo-sounder profiles, seven palaeovalleys have been recognised offshore in Poole and Christchurch Bays. In Poole Bay, Palaeovalleys I, II and III appear to cut southward through the Purbeck-Wight ridge. In contrast Palaeovalleys IV, V, VI and VII in Christchurch Bay do not appear to cut through the Ridge. Valley-filling sediment of significant thickness are found only within Palaeovalleys I and II (Incidently Palaeovalley I has recently been intersected by a civil engineering borehole on the Sandbanks Peninsula)]

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Watson Smith, S. (1934). The Book of Bournemouth; written for the One Hundred and Second Annual Meeting of the British Medical Association held at Bournemouth in July 1934. Published at Bournemouth, 1934. 212 pp., hardcover book with illustrations.


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Webster Smith , B. 1931. The World in the Past: A Popular Account of What it was Like and and What it Contained. 2nd Edition. Frederick Warne and Co. Ltd. London. 365pp.
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West , G.H. 1886a. in: Report of the committee ... appointed for the purpose of inquiring into the rate of erosion of the sea coasts of England and Wales, and the influence of the artificial abstraction of shingle or other material in that action. 6 Christchurch to Poole. Topley, W. (editor). Report of the British Association for the Advancement of Science for 1885, 427-428.

West, G.H. 1886b. The geology of Bournemouth. Proceedings of the Dorset Natural History and Archaeological Society, 7, pp ?.
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White , H.J.O. 1917. Geology of the Country around Bournemouth: Explanation of Sheet 329 [Geological Survey 1 inch to one mile sheet for Bournemouth]. By H.J. Osborne White, F.G.S. 2nd Edition. Memoirs of the Geological Survey, England and Wales. Published by order of the Lords Commissioners of His Majesty's Treasury. Printed by J. Truscott and Son, Ltd, under the authority of His Majesty's Stationery Office. 79 pp. [This is an old edition of the Geological Survey Memoir - see also - Bristow, C.R., Freshney, E.C. and Penn, I.E. 1991. Geology of the Country around Bournemouth. Memoir for 1:50,000 geological sheet 329 (England and Wales). British Geological Survey, London, 116p. There is also the first edition of 1898 by C. Reid. Preface to the Second Edition by A. Strahan, Director: "The first edition of this Memoir, which was written by the late Mr. Clement Reid, was exceptionally brief, a general memoir descriptive of the Hampshire Basin as a whole having been at that time in contemplation. Circumstances have prevented the preparation of the larger work, and opportunity has now been taken ot the exhaustion of the stock of the original pamphlet to produce a memoir on the lines of other New Series Sheet Explanations... continues .. Much of the ground has been re-examined by Mr. White in order to bring the memoir up to date, but the map remains unaltered as the edition published in 1895 and colour-printed (Drift) in 1904."]

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Young , J.A. 1989. The Story of Southbourne. Bournemouth Local Studies Publications, The Professional Education Centre, 40 Lowther Road, Bournemouth, BH8 8NR. No. 695. 50pp.

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Copyright © 2014 Ian West, Catherine West, Tonya Loades and Joanna Bentley. All rights reserved. This is a purely academic website and images and text may not be copied for publication or for use on other webpages or for any commercial activity. A reasonable number of images and some text may be used for non-commercial academic purposes, including field trip handouts, lectures, student projects, dissertations etc, providing source is acknowledged.

Disclaimer: Geological fieldwork involves some level of risk, which can be reduced by knowledge, experience and appropriate safety precautions. Persons undertaking field work should assess the risk, as far as possible, in accordance with weather, conditions on the day and the type of persons involved. In providing field guides on the Internet no person is advised here to undertake geological field work in any way that might involve them in unreasonable risk from cliffs, ledges, rocks, sea or other causes. Not all places need be visited and the descriptions and photographs here can be used as an alternative to visiting. Individuals and leaders should take appropriate safety precautions, and in bad conditions be prepared to cancel part or all of the field trip if necessary. Permission should be sought for entry into private land and no damage should take place. Attention should be paid to weather warnings, local warnings and danger signs. No liability for death, injury, damage to, or loss of property in connection with a field trip is accepted by providing these websites of geological information. Discussion of geological and geomorphological features, coast erosion, coastal retreat, storm surges etc are given here for academic and educational purposes only. They are not intended for assessment of risk to property or to life. No liability is accepted if this website is used beyond its academic purposes in attempting to determine measures of risk to life or property.

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Dr Ian West, author of these webpages

Webpage - written and produced by:


Ian West, M.Sc. Ph.D. F.G.S.

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at his private address, Romsey, Hampshire, kindly supported by Southampton University,and web-hosted by courtesy of iSolutions of Southampton University. The website does not necessarily represent the views of Southampton University. The website is written privately from home in Romsey, unfunded and with no staff other than the author, but generously and freely published by Southampton University. Field trips shown in photographs do not necessarily have any connection with Southampton University and may have been private or have been run by various organisations.
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