West, Ian. 2013. Selsey Bill and Bracklesham Bay: Geology of the Wessex Coast. Internet site: www.southampton.ac.uk/~imw/Selsey-Bracklesham.htm. By Dr. Ian West, Romsey, Hampshire and Southampton University. Revised version: 7th July 2015.
Selsey Bill and Bracklesham Bay, Geology of the Wessex Coast of Southern England

Ian West,
Romsey, Hampshire

and Visiting Scientist at: Faculty of Natural and Environmental Sciences,

Southampton University,
Webpage hosted by courtesy of iSolutions, Southampton University
Aerial photographs by courtesy of The Channel Coastal Observatory , National Oceanography Centre, Southampton.

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SAFETY

Field Geology Safety Warnings

This descriptive geological website does not recommend that you go to any particular place or undertake any particular field work and no responsibility is taken. This website only provides information and it is to explain geological and geomorphological features. It is not an itinerary or programme and you are not being advised to go to anywhere that is described. If you do field work here it is entirely your choice and your responsibility and you do so at your own risk. Normal, sensible procedures should be followed. If you are leading a party then you should write a risk assessment. Some suggestions are made below, but this cannot completely cover all possible risks.

1. Respect private land and private ownership; read warning notices and always be courteous to members of the public. 2. Do not hammer flint pebbles because of very dangerous and fast splinters. 3. Beware of falling on or between rock armour. 4. Avoid any areas of soft mud or soft boggy ground. 5. If conditions are windy or stormy then take care with regard to risk from waves. 6. Wear clothes that are suitable for the weather conditions. 7. Check tides from tide tables in advance, if there is risk of being cut off by the sea. 8. Be prepared to change, divert or cancell the field trip if the weather or sea conditions are severe. 9. Beware of adders (rare). 10. Take a mobile phone for emergencies, and in winter a torch. 11. Avoid any overhanging cliff. 12. Students involved in projects or mapping, here or anywhere are safer if working in pairs. 13. Take care with regard to broken glass, if any, on beaches. 14. With a field party have a first-aid kit available. 15. See that no member of the party is unwell or is left behind because of lack of fitness or good health.

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GEOMORPHOLOGY:

Introduction - Southeastern Bracklesham Bay and Medmerry

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Introduction - The Selsey (Manhood) Peninsula

Medmerry Windmill, Selsey, Sussex, is at the site of a former tidal mill, and is at the margin of the low marshy ground of Medmerry, photo June 2009

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The coast discussed here is part of the Manhood Peninsula. The Manhood Peninsula is the southernmost part of Sussex in England (Wikipedia). It has the English channel to its south and Chichester to the north. The peninsula is bordered to its west by Chichester Harbour and to its east by Pagham Harbour, its southern headland being Selsey Bill. Historically the Manhood Peninsula was known as the Hundred of Manhood. It was founded during the Anglo-Saxon period and had its own courts and local government until the system of hundreds was abolished by act of Parliament in the 19th century. The name Manhood is apparently derived from "men's wood" which applied to a common land forest. Unfortunately this natural forest has gone, and now it is fields, farms and holiday villages. The deforestation has been almost complete and there is hardly a tree to be seen. The ground is mostly a low gravel terrace a few metres above sea-level, but some parts are very close to sea level and flooding can be a problem. The new sea defence work, discussed briefly below is an attempt to deal with part of this problem.

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Introduction - Aerial Photographs

An aerial photograph of the southern part of the Selsey Peninsula, Sussex showing possible problems of sea flooding in the Medmerry area

More detail shown of the Medmerry area of the Selsey Peninsula, Sussex, shown on a medium-scale aerial photograph

A close aerial view of the southeastern part of the Medmerry coast, Bracklesham Bay, near Selsey Bill, Sussex, June 2007

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Bracklesham Bay at Bracklesham

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A high and steep shingle beach at Bracklesham seafront, Bracklesham Bay, Sussex, June 2009

The long shingle beach at Medmerry looking from Bracklesham to the built-up area of Selsey, near Selsey Bill, Sussex, 21st June 2009

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MEDMERRY COAST - SELSEY PENINSULA

Medmerry Coast - Introduction and Access

West Street, Selsey, is an access route to the coast of Medmerry at southeastern, Bracklesham Bay, Sussex, photograph 24th June 2015

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An introductory view, looking northwest, of the sea-defended coast of Medmerry, Bracklesham Bay, Sussex, 24th June 2015

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A robust, new concrete wall, and older groynes, are protecting new houses, near the end of West Street, Selsey, Sussex

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Some views of coastal sea defences in the West Street area of Selsey are shown above. The concrete wall seems quite strong and robust. Examine the area on Google Earth to observe that the coast here is out-of-line in comparison with the stretch of conserved, retreating, undeveloped coast between here and the Medmerry Park Holiday Village. The sea defences have worked, but this part of this Selsey is dependent on artificial concrete constructions. They have been successful, but this area is very different from a natural coast. The similarity in positions of the shingle on either sides of the groynes suggests that there is not much longshore drift here. This is because the coast faces the prevailing, southwesterly storm wave direction.

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Medmerry - SCOPAC Report

The SCOPAC Report on the Selsey Peninsula, gives a very good introduction to the Medmerry area. See the full report. Here is a shortened version of relevant extract from a previous date (date uncertain):

"The Environment Agency and its predecessors have conducted a long-term nourishment and re-profiling scheme at the critical Medmerry barrier beach site ... This has a long history of intermittent landward migration. Its present form dates to approximately 1600, when it was reported to have blocked a former tidal inlet channel. Subsequently, it has breached and reformed on several occasions (Bone, 1996). However, in recent years it has exhibited increasing instability, and has experienced regular cutbacks, overtopping and breaching. It has necessitated increasingly urgent nourishment and profile reconstruction in order to maintain the present defence line.. . This sector of beach is in a condition of chronic disequilibrium, unable to adjust to natural gravel losses and foreshore lowering. ... It is located at a focal point for wave erosion due to refraction induced by complex offshore relief. The initial nourishment was in 1976 ... involving deposition of 14,500 cubic metres of shingle and extension of groynes to Low Water Mark. The main phase was .. between 1976 and 1980, with the addition of 225,000 cubic metres of gravel obtained from inland gravel pits... The nourishment material comprised nodular flint gravels significantly coarser and more angular than indigenous beach material. The scheme also involved insertion of 38 groynes along a 3.8 km frontage... The artificial beach was re-profiled.. . Further replenishment .. was completed between 1989 and 1996.... Several major storm surges during the winters of 1998-9, 2000-1, 2001-2 caused overwashing, crest lowering, beach drawdown, with a 300m breach in 1999. This has necessitated the emergency dumping of over 500,000 cubic metres of gravel (from inland sources), together with profile reconstruction. By the mid-1990s the groyne field had deteriorated .... "

NB. This then was the situation prior to the major work and the new cut of 2012-1013. The studies and work seem to assume that a natural situation was unsatisfactory and work must be done. A reasonable discussion point is why could it not have been just left to nature, and human activities behind the beach driven to make their own local adjustments? However, that is a purist viewpoint, and the present culture requires the Environment Agency and Scopac to look into and take action on coastal protection.

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Medmerry - Sea Front at Medmerry Park Holiday Village
Introduction - 2008-2009

Medmerry is at the southeastern end of the Bracklesham Bay shingle beach. It is near Selsey Bill. A major feature is the Medmerry Park Holiday Village, a large holiday home site, where you can buy holiday bungalows or chalets. It has central facilities close to the beach. The Holiday Village was badly flooded in 2008. Some discussion of this is given below.

Major flooding of the Caravan site at Medmerry took place during a storm and storm-surge on the 10th March 2008. Sea-level was raised by about 1 metre above the normal level at Southampton.

Here is an old press report mainly from the Environment Agency, but originally available in the website of Heart Radio Station. It gives an idea of the former situation before the recent sea defences were constructed.

Selsey Flood Update - March 2008:

After a night of further heavy winds and high tides, the Environment Agency is now battling to reinstate the shingle bank at Medmerry beach in Selsey. A flood warning is still out for the coastline from Chichester Harbour to Selsey Bill and Broad and Earnley Rifes in Selsey which means some flooding is still expected. An 800 metre section of the shingle bank, which provides flood protection to the large caravan site (2,200 caravans) and 650 hectares of land, was washed away by the storms and high tides yesterday afternoon. Half of the caravan site was flooded and 50 caravans were destroyed.
Environment Agency staff worked through the night to monitor the weather situation along with the tides and using bulldozers and excavators to rebuild the defences as much as possible ahead of the high tides. Although there was some flooding on these second high tides, the levels were lower than those of yesterday.
Six bulldozers will be working on the beach throughout the day to push up the shingle that is currently there. Once the weather settles and the water levels have gone down, the shingle will be imported to reprofile the beach.
James Humphrys, Environment Agency Solent and South Downs Area Manager, said: "The Environment Agency is already working with local communities who live along this very fragile coastline to determine how we manage it into the future. All of our research suggests that a realignment of defences inland in a managed way is the right thing to do. This would reduce the risk of flooding to people with the added benefit of less maintenance required."
"It is of little surprise that a storm of the intensity we saw yesterday, together with the high tides, caused this flooding. The shingle is kept in place year on year only because of our extensive and very costly maintenance programme. This is a very exposed and low lying coastline, and we expect large winter storms to cause breaches."
"The cost of replacing the shingle following yesterday's storm will run into hundreds of thousands of pounds and there are no guarantees that we won't see a repeat of this storm event in the near future, causing it all to be lost again."
"The Environment Agency, together with Chichester and Arun District Councils, is currently working with communities along this part of the coastline to consider options for managing flood risk and coastal erosion here over the next 100 years. The next stage of formal consultations on the options will start this spring."

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A general view of the sea front of Medmerry Village Holiday Park, Selsey, in 2009, before major sea defences were emplaced in 2012-2013, southeastern end of Bracklesham Bay, Sussex

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Old sea defences of sheet piling at Medmerry, Selsey, Sussex, 21st June 2009

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Sheet piling and concrete damaged by storms at the caravan site , Medmerry, Selsey, Sussex, 21st June 2009

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Medmerry - Sea Front at Medmerry Park Holiday Village in 2015
(after work in 2013)

The top of the beach at Medmerry Park Holiday Village, Bracklesham Bay, Sussex, near Selsey Bill, 24th June 2015

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Medmerry Park, Bracklesham Bay, Sussex, seen from the northwest, after new sea defence measures were put in place

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The southern of the two groynes of dark grey larvikite on the beach near Medmerry Park Holiday Village,  Bracklesham Bay, Sussex, 24th June 2015

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The robust northwestern groyne of larvikite, just beyond Medmerry Park Holiday Village, Bracklesham Bay, Sussex, 24th June 2015

The larvikite groyne shown above is the northwestern of two separate rock armour groynes which are on two sides of the beach of the holiday camp. The one shown is a well-defined seaward groyne, quite distinct, but oblique to the beach. Walking northwest there is no need to cross it because the beach behind it is continuous. There is a still, however, a further larvikite barrier to the northwest. This more formidable obstacle extends from the sea inland for, perhaps several hundred metres. To reach the new sea opening it is necessary to cross that one. (The photograph below is of this final barrier).

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Blocks of larvikite rock armour in the northwestern coastal barrier, not groyne, of Medmerry Park Holiday Village and sea front, Bracklesham Bay, Sussex, 24th June 2015

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A very robust embankment of larvikite rock armour, north of Medmerry Park Holiday Village, southern part of Bracklesham Bay, Sussex, 24th June 2015

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By 2015, the Medmerry holiday village looks much the same. The sea defence situation, though, has changed drastically because of work in about 2013. The beach in front has been changed from its previous state (e.g. in 2008). It still is a fairly natural, flint shingle beach. Howwever, shingle may have been added. A drastic change has the construction of major sea barriers of dark grey, larvikite rock armour both southwest and northeast of the central beach front of Medmerry Park Holiday Village. Larvikite is a very tough and resistant, intermediate igneous rock that comes from Larvik and adjacent areas of the Oslo Graben, Norway. It is easily recognised by both the general colour and schillerization of the large, anorthoclase (sodium and potassium) feldspar crystals, with their oblique cleavage.

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In terms of igneous rock classification a few simple points can be noted. This is a coarse-grained, plutonic rock, very feldspar rich, but containing much less quartz than a granite. It is not as hard as granite. It is also darker-coloured. The major constituents are feldspars. These, however, tend to have a complex composition somewhere in the middle (i.e. anorthite) between the alkali feldspars and the plagioclase. This places the rock as a type of monzonite, right in the middle of in the igneous rock classification scheme of Strecheisen, as shown below (it can sometimes be an augite syenite). The rock occurs in the Larvic Batholith in Norway. This structure developed during the formation of the Oslo Rift, within gneisses. The feldspars indicate that it formed under deep crustal conditions.

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Streckeisen classification for the plutonic rocks with mafic minerals less than 90

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This rock is extensively quarried in Norway and exported for sea defences. On the coast, it is more resistant to erosion than is limestone, and thus in groynes it tends to retain some sharp, rather hazardous edges. Its dark grey colour contrasts with the light colour of southern England, sand and shingle beaches (and cliffs of light-coloured sedimentary strata). However, the ugly rock may serve its intended purpose as a barrier very well and perhaps the aesthetic aspect is not important.

[Additional notes from Wikipedia:
"Rock Armour"
"Also known as riprap, rock armour are large rocks piled or placed at the foot of dunes or cliffs with native stones of the beach. This is generally used in areas prone to erosion to absorb the wave energy and hold beach material. Although effective, this solution is unpopular due to the fact that it is unsightly. Also, longshore drift is not hindered. Rock armour has a limited lifespan, it is not effective in storm conditions, and it reduces the recreational value of a beach. The cost is around 3000 pounds per metre, depending on the type of rocks used." (Another source quotes 1000 to 4000 pounds per metre. - It is not cheap!)]

A further and major change is that to the northwest of the Park, and beyond a larvikite barrier, is the location of a new sea-inlet scheme. An artificial channel has been cut and whereby the sea is now let in through the beach bank to flood (at least at high tide) an appreciable area of the land behind. This was finished in 2013. Previously the shingle bank was complete and continuous, and then it was possible to walk from the village of Bracklesham southeast to Medmerry and on to Selsey Bill. This is not possible now. Some photographs given here the new artificial arrangement.

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A replenished and reconstructed shingle bank at Medmerry, Selsey, Sussex, showing the low ground around Broad Rife at the back which, although protected in normal conditions, is still at risk of flooding during great storms

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GEOMORPHOLOGY:

Sea Flood Defences - Medmerry - New Cutting through the Beach

The new sea defences and the new sea inlet at Medmerry and adjacent areas near Selsey, were very expensive. The cost was 28 million pounds. The rock armour, referred to above, would have been a major part of this cost.

An oblique downward vieward of the new cutting to let seawater in and out at Bracklesham Bay, Sussex, June 2015

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A new, artificial opening from the sea through the shingle beach at Medmerry, Selsey Peninsula, Sussex, June 2015

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Saltmarsh deposits exposed in front of the flint-shingle beach at the new cutting in Bracklesham Bay, Sussex, 24th June 2015

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Contorted, laminated marsh silt deposits at the new artificial sea entrance, southern side, Bracklesham Bay, Sussex, 24th June 2015

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New sea defences have been built recently, just northwest of the Holiday Camp at Medmerry. The shingle beach has been artificially breached in 2013, and new sea walls built inland. Photographs above shows the narrow, artificial breach in June 2015 with a rising tide. For more information on this see the BBC report, summarised below:

See BBC News, 4th November 2013.
See: Sea surrender plan to ease flood fears on the south coast.

The following is a shortened and modified account, based on the BBC report, which should be seen in full online.

A scheme to combat flooding by surrendering land to the sea was completed on the south coast in November 2013. The 28m "managed realignment" at Medmerry in West Sussex involved the building of 7km of new sea walls up to 2km inland. By letting the waters in, the nvironment Agency says the risk of flooding for hundreds of homes will be reduced. The surrendered land will become a wetland habitat for many species. The sea has long been threatening the flat land of the Manhood [or Selsey] Peninsula that on the coast between Portsmouth and Worthing. Caravan parks in Selsey and Bracklesham Bay have been flooded by the sea a number of times in recent years.
The Environment Agency plan required the destruction of the existing sea wall at Medmerry and the artificial flooding by sea water of some of the land nearest to the coast. 60,000 tonnes of rocks, dark grey larvikite from Norway, have been imported by ship to reinforce the works. 350 homes, two holiday parks and a water treatment works will have increased protection. There are 7km of sea-defences built further inland from the coast. The development able to withstand a once in a thousand year flood.
The change is partly being forced on the Agency because of EU egislation that requires compensation for the loss of wildlife habitat through development. The Medmerry scheme makes up for the loss of similar conservation areas in and around the Solent. [the account continues.]
[End of summarised BBC report.]

Comment by the present author:
Note that the area is in the Chichester earthquake region. The fairly frequent earthquakes are usually small and unlikely to have any significant effect on the sea defences. The big 1638 Chichester earthquake not only caused much destruction in the city, it also threw up a large cloud of sulphurous and bituminous-smelling gas. This could have come from nearby oilfields, but it is more likely that it came from a violent shaking of marshes and mudflats in the area. A repeat may or may not directly affect the new sea defence scheme in some way but it is unlikely to affect the big larvikite barriers. A tsunami from an earthquake, perhaps a distant one, is possible, though, and they occasionally occur in the region (one has been recorded at Hurst Spit, further west, and there may have been others from time to time). For more information on the local earthquakes see:
Earthquakes of the South of England .

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LOCATION

Medmerry Coast, West of Selsey Bill - Raised Beach, Sarsens and Erratics

Seen from the promenade, the southeastern end of the natural cliff exposure at Medmerry, Bracklesham Bay, near Selsey Bill, Sussex, 24th June 2015

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The southeast end of the Medmerry, Pleistocene, raised beach, cliff exposure, southeastern end of Bracklesham Bay, near Selsey Bill, Sussex, 24th June 2015

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The raised beach cliff, southeast of Medmerry Park area and towards the old coastguard lookout, Bracklesham Bay, Sussex, 24th June 2015

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Fairly rounded, white, flint pebbles in the Pleistocene, raised beach deposit at Medmerry, Bracklesham Bay, near Selsey Bill, Sussex, 24th June 2015

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Pebbles of the Pleistocene raised beach at Medmerry cliff, Bracklesham Bay, near Selsey Bill, Sussex, 24th June 2014

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Raised beach west of Selsey Bill, Sussex, old photograph, in 2004

Pebbles orientated vertically in the raised beach, west of Selsey Bill, Sussex, old photograph, in 2004

A coastguard station with a prominant tower is situated on the western side of Selsey Bill, not far from Crablands Farm and from the Medmerry Windmill and the large caravan park. The map reference of the coastguard station is SZ 845930 and it is clearly marked on the Ordnance Survey map - Explorer 120 - Chichester, South Harting and Selsey, 1:25,000. There are concrete sea-defences at the coastguard station but to the northwest there is an eroding coast with a low cliff. This reveals an excellent section in the Ispwichian (last interglacial) raised beach deposit of rounded pebbles, as shown in the photographs above. Over this is brown brickearth, which when unweathered can be calcareous with chalk solifluction debris. In normal conditions it is not usually possible to see what lies beneath the raised beach pebble bed. The present beach obscures the lowest part. At very low tides after exceptional storms more may be revealed. In late Victorian times there was much interest in the discovery here of a two ton mass of Bognor rock with striae like those in glacial deposits.

In 1892 Clement Reid discussed an unusual exposure of erratics at the base of the Ipswichian raised beach deposit at Medmerry. The exposure resulted from a storm of October 24th in 1891.

Erratics exposed by the 1891 storm, Medmerry, Selsey, Sussex

"During the continuous south-westerly gales of last autumn and early winter, the loss of land on the west side of Selsey Bill was extremely great. Not only was the cliff line cut back several yards, but the scour was so strong as to remove most of the beach and lay bare platforms of Eocene and Pleistocene strata at a level where we usually find nothing but beach-shingle. Immediately after the storm of Oct. 24th I re-examined the coast close to Selsey, and found that erosion had been particularly marked opposite Medmerry Farm, where the sea had undermined one corner of the farm buildings, though in 1898 it was about 20 yards away. This cutting back of the cliff, and the concurrent removal of most of the beach on the foreshore opposite, exposed a section unlike anything which had been seen, though the unusual abundance of large erratics on the foreshore had always led me to suspect that this was the critical point, and that there was a probability of finding the glacial deposit in place in the immediate neighbourhood.

Below the level of mean tide there was seen only a wide expanse of fossiliferous Bracklesham Clays full of Corbulae [note that Corbula is abundant in the Cypraea Bed or Brook Bed, S6 to S9 of the Selsey Formation, Bracklesham Group, which crops out quite close to Medmerry Windmil - see Curry et al. 1977], but at a level slightly higher, on the part of the foreshore first laid bare by these storms, the junction of the Eocene and Pleistocene strata was exposed. The relations of the two deposits were so peculiar as to at once attract attention. The junction was neither smooth nor channelled, as is ordinarily the case, but the whole surface of the hard Eocene clays, for a quarter of a mile, was full of basins or pits from 2 to 6 feet [about 2 metres] across. These pits were usually unconnected with each other, and strike one as a feature totally unlike the irregular eroded channels formed by running water between tide-marks. Many of the pits had nearly vertical sides and were 2 feet or more in depth, but it was difficult to ascertain the extreme depth, for on each occasion when the section was well-exposed the pits were full of water, and time and the tides would not allow me to bale out or drain many of them.

Four out of every five of the basins contained nothing but loose gravel, with a few valves of Balanus and rare fragments of marine mollusca. The loose material, except where cemented by iron oxide, has been almost entirely removed by the recent storms, which were not able to make much impression on the harder Bracklesham Clays. The remainder of the basins were much more interesting, for each contained an erratic block, which had not merely been dropped, but showed signs of having been forcibly squeezed or screwed into the clay, until its upper surface was flush with the general level. In this process the softer and more splintery rocks had been crushed, so that they are now found with their angular fragments slightly separated by gravel, or by fossiliferous Eocene clay. The harder masses were driven into the clay so that I was obliged to cut away fossiliferous Eocene clay to get out the Pleistocene erratic. It seems clear that most of these pits are not hollows eroded by water, but dents made by the ice or by erratics; for the stratified Eocene clays generally become much disturbed and contorted around the margin of the hole. The pits filled with finer material probably mark the spots where large erratics were formerly deposited, though, becoming again frozen into the ice-foot, they were lifted out and transported to fresh sites.

About a hundred of these pits were examined, and the conclusion seemed irresistible that they afforded clear evidence of the agency of floating ice. Drift-ice grounding on the ancient foreshore dropped its burden of erratics between the tide marks. Here they were pressed deeper and deeper into the clay, for the rise and fall of the tide at high-water piled ice upon any projecting rock, while at low water the rock was pressed down by the weight of the ice till it was flush with the general surface. Often, however, the still-projecting boulder would be firmly frozen into a new ice foot, or accumulated mass of pack-ice, and would then be gently lifted out of the hole at the rise of the spring tides. It is thus that I account for the occurrence of emptly pits, for they seem to mark the former sites of blocks which may have shifted their position several times before finally coming to rest. Perhaps some of the basins were produced by the stranding, packing and revolving of masses of ice during a storm, but the general appearance of the section suggests tranquil water in a sheltered bay. No signs of furrows ploughed in the clay were observed, and the ice was probably entirely in the form of flat-bottomed ice-foot, which, at a spot like this, sheltered from the prevalent winds by the Isle of Wight [but note that the prevalent wind-direction then is not known], would ground gently and would tranquilly melt away without being driven violently into the shoals, as on a more exposed coast."

Erratics belonging to the following rock types were recorded by Reid . See the original paper for more accurate measurements, which are given in feet and fractions of feet.

1. Bembridge Limestone, cream-coloured and with moulds of Limnaea [Galba ]. Four blocks studied, mostly about a third of a metre in length.
2. Bognor Rock, from the London Clay of the Bognor area (Bognor Ledge). Hard sandstone or calcareous grit, usually with Pectunculus brevirostris. Six blocks, some almost 2 metres in length. One block was bored. One large block was 5 feet by 4 feet and probably weighed more than 2 tons. This contained Pectunculus brevirostris and Voluta denudata and had been striated by ice. There is a photograph in Reid's paper.
3. Sarsens. Tertiary quartz-cemented sandstone. Four blocks, about a third to half a metre in length.
4. Black Flints from the Upper Chalk. Size was not specified.
5. Upper Greensand, probably from the Isle of Wight. Glauconitic sandstone, some cherty and some phosphatic, and also dark-coloured chert with sponge spicules. One large block of glauconitic sandstone was more than 2 metres in length. Most of the others were of about a third of a metre in length.
6. Hard pale green and reddish sandstone, probably Palaeozoic. About half a metre in length.
7. "Greenstone". Palaeozoic. About a third of a metre in length.
8. Granite of muscovite-biotite type. About a third of a metre in length.

Compared to a list of the rock types which have been found as erratics in the deposits of the neighbourhood of Selsey, the Medmerry rocks are unusual in including a predominance of erratics from localities within 20 miles of Selsey. The general list for the region includes many igneous rocks. Reid suggested that the local rocks, being less resistant, have in many cases disintegrated at some stage. Thus in time the harder igneous rocks become proportionally more dominant. Medmerry is important in revealing the original relative abundance of local material.

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LOCATION - BRACKLESHAM BAY

Sarsens and Erratics

Erratics of various foreign rocks, including basalt, diorite, syenite, granite, gneiss, etc., ranging up to 1.5m in maximum diameter and sarsens attaining greater dimensions, occur on the shore of Bracklesham Bay near Cakeham and East Wittering. They are occasionally seen in the low cliffs (White, 1915).

The fossiliferous mud-deposit of West Wittering occurs east of the entrance to Chichester Harbour. It crops out on the shore to west of West Wittering beacon but is obscured for long periods by accumulations of sand and shingle. There is an ancient eroded channel with Rhinoceras and Elephas, together with Corbicula fluminalis, Succinea oblonga and Hydrobia marginata (Reid, 1891 in White, 1915). The gravelly base is full of redeposited erratics. White marl with chalk grains was seen above this gravel at one place.

Important evidence for the age of the stones comes from West Wittering where peaty clays above the gravel with erratics is fossiliferous. This topic is discussed in the Dating of the Erratics Section".

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LOCATION:

Pagham Harbour

A general view of Pagham Harbour at high tide, looking from Church Norton northeastward towards Pagham Church, Sussex, 22nd June 2009

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ACKNOWLEDGEMENTS

I thank those visitors and students who have occasionally accompanied me, for their assistance, at various Selsey and Bracklesham locations. Most field photography has been done alone, though.

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References and Bibliography

Please also go to Solent Bibliography - General .


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Bates, M.R. , Parfitt, SA and Roberts, M.B. 1997. The chronology, palaeogeography and archaeological significance of the marine Quaternary record of the West Sussex coastal plain, southern England, UK. Quaternary Science Reviews, 16, 1227-1252.

Bates, M.R. 2001. The meeting of the waters: raised beaches and river gravels of the Sussex coastal plain / Hampshire Basin. In: Wenban-Smith, F.F. and Hosfield, R.T. (Editors) 2001. Palaeolithic Archaeology of the Solent River. Lithic Studies Society Occasional Paper, No. 7, 2001, 111pp. Proceedings of the Lithic Studies Society day meeting held at the Department of Archaeology, University of Southampton on Saturday 15th January 2000.
Abstract:
Integrating Pleistocene sediments from continental systems and the marine stratigraphic record is a key objective for Quaternary science. In many cases correlation of these records is only possible through comparison of proxy records. However, this objective may be realised in those areas of the world where marine marginal sediments occur in close proximity to terrestrial fluvial deposits in the lower reaches of major river valleys. One such location is the Sussex/Hampshire corridor in southern England. Pleistocene sediments within the area of the former Solent River system and the West Sussex Coastal Plain are evidence for a wide variety of different depositional systems ranging from temperate flood plains and marine beaches to cold climate braided river channels. These deposits may contain archaeological material such as handaxes as well as faunal and floral remains. The proximity of sediments of both temperate and cold climate types within the lower reaches of the modern major river valleys should allow correlation between the temperate and cold climate stratigraphic records in this area. This evidence may be used to link the marine and fluvial stratigraphic records. This paper describes the nature of the different types of evidence from the Sussex/Hampshire corridor and considers some of the problems and pitfalls in the use of this information in the construction of an integrated stratigraphic frameworkfor the area.
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Bone, A. and Bone, D. 1985. Fossils from Bracklesham to Selsey. Private Publication, 32 pp. 8 pls. Chichester.

Bone, A. E. 1996. The Shaping of the Selsey Coastline: A Review of the Geomorphology, Archaeology and History. Tertiary Research, 16, 5-14.

Bone, D.A. and James, J.P. 1975. Report of field meeting to Chichester Harbour, Sussex. Tertiary Times, 2/3, 99-100.


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Brown, A.R. 1981. The Changing Geography of the Harbour. in: R W Rayner (Ed.)The Natural History of Pagham Harbour, Bognor Regis Natural History Society, pp. 1-13.
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Bradbury, A.P. 2001. Strategic monitoring of the coastal zone: towards a regional approach. Report to SCOPAC, South Downs Coastal Group, South East Coastal Group and Environment Agency, 91p.


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Bray, M.J. and Cottle, R. 2003. Solent Coastal Habitat Management Plan. Volumes 1 and 2. Report by Posford Haskoning and University of Portsmouth to English Nature and Environment Agency. Volume 1 Summary of Habitat Change 66p. Vol 2 Technical Report 219p. Volume 1 Summary of Habitat Change 66p. Vol. 2, Technical Report 219pp.

Bray, M.J. and Hooke, J.M. 1997. Coastal cliff prediction with accelerating sea-level rise. Journal of Coastal Research, vol. 13 (2), pp. 453-467.

Bray, M.J., Carter, D.J. and Hooke, J.M. 1992. Sea-Level Rise and Global Warming: Scenarios, Physical Impacts and Policies. Portsmouth Polytechnic. Report to SCOPAC. 205 pp.

Bray, M.J., Hooke, J.M. and Carter, D.J. 1994. Tidal Information: Improving the Understanding of Relative Sea-Level Rise on the South Coast of England. University of Portsmouth, Report to SCOPAC, 86 pp.

Bray, M.J., Hooke, J.M. and Carter, D.J. 1997. Planning for sea-level rise on the south coast of England: advising the decision-makers. Transactions of the Institute of British Geographers, N.S., 22, 13-30.

Bray, M.J., Hooke, J.M. and Carter, D.J. 2000. Sea level rise in the Solent region. Pp. 101-102 in: Collins, M. and Ansell, K. 2000. Solent Science - A Review. Elsevier, Amsterdam, 385pp. By M.I. Bray, I.M. Hooke and D.l Carter of the Department of Geography. University of Portsmouth, Buckingham Building, Lion Terrace, Portsmouth, PO1 3HE, U.K. [Extract:] Introduction: Sea-level has been a major factor in the evolution of the Solent Rapid post-glacial sealevel recovery, between 15,000 and 5,000 years BP, inundated the system and continuing rising sea-levels control contemporary biogeomorphologicaI environments; similarly, they pose a potential threat to human occupation and uses. Concerns relating to the future effects of climate change and sea-level rise have led to several studies specific to the Solent region (Ball et al., 1991; Bray et al., 1992, 1994, 1997). [This is a short paper; see the other Bray publications for more detail. Marsh sedimentation results of local relative sea-level (Cundy and Croudace, 1996) indicate 4 to 5 mm per annum at present. A model indicates increase in rate to 6.5 mm per annum by 2050 but there, of course, uncertainties.]

Bray, M.J., Hooke, J.M., Carter, D.J. and Clifton, J. 2000. Littoral transport pathways, cells, and budgets within the Solent. Pp. 103-106 in: Collins, M. and Ansell, K. 2000. Solent Science - A Review. Elsevier, Amsterdam, 385pp.


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Cobbold, C. and Santema, r. 2001. Going Dutch on the Manhood Peninsula. Rotterdam: van Walsberge, 79 pp.


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Cope, S.N., Bradbury, A.P. and Gorczynska, M. 2008. Solent Dynamic Coast Project. Main Report. [By Dr. Samantha Cope and others]. A tool for SMP2 [Shoreline Management Plan 2 for the Solent area. ]. Channel Coastal Observatory. NOC, Southampton. January 2008. www.channelcoast.org. Publicly Available. Online as a pdf file. This is a very large document with numerous coloured maps and diagrams. Go to Channel Coastal Observatory - Reports. It deals with such matters as Lymington, Pitts Deep and Sowley, Beaulieu River Estuary, Calshot, Chichester, Selsey area, Pagham Harbour etc.
Go to: Solent Dynamic Coast Project. (2015)
"The Solent Dynamic Coast Project (SDCP) was conducted to inform development of the North Solent Shoreline Management Plan (SMP) to ensure compliance with the requirements of the European Union Habitats and Birds Directives. The focus was on mudflat and saltmarsh habitats as these form the largest expanse of coastal habitats across the north Solent that are immediately under threat from climate change and coastal management decisions. The consequent effect to coastal grazing marsh was also considered." [continues with main objectives.]
For further information please contact Dr Samantha Cope. Tel 023---598469 [full number given online, but cut here]. email: snc@noc.soton.ac.uk
Downloads available: SDCP Summary 1 [3Mb] [subscribe]; SDCP Summary 2 [15Mb] [subscribe]; SDCP Summary 3 [10Mb] [subscribe]; SDCP Main Report 1 [10Mb] [subscribe]; SDCP Main Report 2 [18Mb] [subscribe]; SDCP Main Report 3 [10Mb] [subscribe]; SDCP Main Report 4 [10Mb] [subscribe].

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Cordiner , R. 2006. The Cretaceous and Palaeocene Geology of Chichester Harbour. By Roger J. Cordiner of Bognor Regis, West Sussex. Geode Publications, Bognor Regis, September 2006. A copy can be ordered from Roger Cordiner, 39 Devonshire Road, Bognor Regis, West Sussex, PO21 2SY for 6 pounds plus 1 pound, 50 pence, postage etc..

Cordiner, R. 2006. The Quaternary Geology of Chichester Harbour. By Roger J. Cordiner of Bognor Regis, West Sussex. Geode Publications, Bognor Regis, September 2006. A copy can be ordered from Roger Cordiner, 39 Devonshire Road, Bognor Regis, West Sussex, PO21 2SY for 6 pounds plus 1.50 postage etc.
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Etheridge, R. 1883. Address of the President of Section C - Geology. Report of the British Association for the Advancement of Science, 52nd Meeting at Southampton in August, 1882. Transactions of Section C, pp. 502-529. By Robert Etheridge, F.R.S.L. and E., F.G.S., Assistant Keeper of the Geological and Palaeontological Department of the Natural History Museum (British Museum), London.[Consideration of the Eocene and Oligocene strata of Selsey, Bracklesham Bay, the Isle of Wight, Bournemouth, Hengistbury Head etc. The Brockenhurst Bed of the New Forest (Whitley Ridge railway cutting) and the Isle of Wight is discussed. Much of the information is from previous works such as Fisher, and Forbes but additional details are given. Edwards' fossil collection and correlation of Hampshire Basin strata with German and Paris Basin successions are other topics in this paper.]

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Fisher, O. 1862. On the Bracklesham Beds of the Isle of Wight basin. Quarterly Journal of the Geological Society, London, 18, 65-94. By the Reverend Osmund Fisher of Cambridge University. [An early, but well-known, key paper on the details of the Bracklesham stratigraphy. It provides detail on Lee-on-the-Solent, Whitecliff Bay, Bracklesham Bay and other localities.]
"Introduction. - We are indebted to Mr. Prestwich for a clear conception of the age of the Bracklesham series, and of its place among the Eocene Tertiaries; while the late Mr. Dixon has described the fossils of Bracklesham and Selsey, and given a very interesting account of the coast of that part of Sussex. In the course of collecting specimens from these beds during the last eight years, I have been led t think that there are many points of interest on which a more minute description of the succession of their subordinate divisions, and of the fossiliferous localities might be acceptable." --- (continues)

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Fisher , O. 1871. Portland wood, on the coast of Sussex. Reply to Mr. Perceval. Geological Magazine, 8, 524-525, Correspondence. By the Reverend Osmund Fisher, who described Purbeck strata in Dorset.
Sir - I know the Portland beds of the Dorsetshire district pretty well, and as far as I am aware, the Tisbury Isastraea does not occur there at the present day. But, considering that there are fragmentary patches of Portland beds fringing the coast for a considerable distance in Dorsetshire, it is highly probable that, in not very distant times, there was a considerable area occupied by them there; as indeed there probably is now beneath the Channel. The Portland beds vary in character rather rapidly at places not far from one another, so that the non-occurrence of a particular fossil in those now visible, need not lead us to conclude that it may not have occurred not very far off in distant times.
I would, however, recommend Mr. Perceval to obtain an accurate determination of his fossil so as to be sure of its specific identity.
That erratics from the Portland beds have found their way into Sussex, I believe to be a fact; for I saw in 1866 a block of indubitable Porland fossil wood at Selsey, in the garden of Mrs Pullinger [perhaps some connection here to Colin Pullinger of Selsey, who invented the humane mousetrap and had a mousetrap factory.] I was informed that it was found on the beach at that part of the shore called the "The Park" [is this near Park Farm, there were originally two Bishop's Parks near Selsey]. It had been described to me as a petrified piece of wood from the submarine forest, which occurs along the coast; and my curiosity was raised, knowing that such wood was never petrified. I think that the story was true and certainly not improbable, because there can be little doubt that the numerous glacial erratics of that coast have travelled up the Channel from the direction of the Channel Islands. And it is quite likely that a block of silicified wood from Portland, almost as indestructible as any igneous rock among them, may have come in the same manner and from the same direction. The block was eighteen inches long and ten inches in diameter. O. Fisher, Harlton, Cambridge.
[Incidently and possibly of relevance to Fisher's note, I (Ian West in 2015) have found loose pieces of Kimmeridge oil shale, exposed in the cliffs of Dorset, on the shingle beach and Medmerry and near Bracklesham. It may be common, because I have not searched systematically. It probably comes from the Raised Beach erratics.]
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Godwin Austen, R.A.C. 1857. On the Tertiary deposits of the Sussex coast. Quarterly Journal of the Geological Society, London, 13, 40-47.

Graves, J. C. 1981. The reclamation of Pagham Harbour through the Centuries. Journal of West Sussex Archives Society, vol. 20, pp. 2-5.

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Heron-Allen, E. 1911. Selsey Bill: Historic and Prehistoric: A Map and Guide to Selsey. London.
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Hodgson, J.M. 1964. The low level Pleistocene marine sands and gravels of the west Sussex coastal plain. Proceedings of the Geologists' Association, 75, 547-561.
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Hopson , P.M. 2000. Geology of the Fareham and Portsmouth District, A brief explanation of the geological map Sheet 316 Fareham and part of Sheet 331 Portsmouth. British Geological Survey.


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Johnson , J.P. 1901. The Pleistocene fauna of West Wittering. Proceedings of the Geologists' Association, 17, 261-264.

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Kellaway , G.A. 1971. Glaciation and the stones of Stonehenge. Nature, London, 232, 30-35.

Kellaway, G.A., Redding, J.H., Shephard-Thorn, E.R. and Destombes, J.P. 1975. The Quaternary history of the English Channel. Philosophical Transactions of the Royal Society, A.279, 189-218. Abstract: Several lines of evidence for former glaciation of the English Channel are considered. These include the following major geomorphical features: (1) extensive areas of flat featureless sea bed bounded by cliffs with residual steep-sided rock masses rising about 60-150 m above them, (2) terrace forms bounded by breaks in slope or low cliffs, (3) palaeovalley systems related to the present land drainage, (4) enclosed deeps (fosses); all except (3) may be attributed to a glacial origin. The distribution of erratics on the Channel floor and in the modern and raised beaches of its coasts are attributed to widespread Saalian glaciation. This glaciation was responsible for the deposition of morainic material at Selsey and the damming-up of glacial Lake Solent. The so-called' 100 foot raised beach' of west Sussex is now re-interpreted as a fluvioglacial deposit laid down at the northern margin of the English Channel ice. It is thought that at the height of the Saalian glaciation mean sea-level fell to between 90 and 180 m below O.D. and that for a time the ice was grounded near the western margin of the continental shelf. Possible reconstructions of the limits and main movements of the Weichselian and Saalian ice sheets covering the British Isles and English Channel are included. [Interesting but controversial theory. Well-referenced and with very useful observations.]
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Kemp , David John . (late specialist on the Bracklesham Group and fossil fish remains, including sharks' teeth, from these and other Eocene strata. He was the author of many papers and has an excellent collection of local fossils on display at Gosport Museum.)

Kemp, D.J. 1977. A Brief Illustrated Account of the English Eocene Shark and Ray Fossils. Published by the Gosport Museum, Gosport, Hampshire, November 1977. Six pages with tables, and with 11 plates of fish fossil remains. Original price - 75 pence.

Kemp, D.J. (David John Kemp). 1982. Fossil Sharks, Rays and Chimaeroids of the English Tertiary Period: A Complete Illustrated Guide. Gosport Museum, 1-47, 10 figs, 3 tables, 16 plates. First editionw was 1977. This is the second edition of 1982. Printed by Gosport Borough Council. Original Price - 1 Pound, 50 pence.

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Long, A.J. and Tooley, MJ. 1995. Holocene sea-level and crustal movements in Hampshire and Southeast England, United Kingdom. In: Holocene Cycles: Climate, SeaLevels and Sedimentation. Frinkl Jr. (Ed.). Journal of Coastal Research, Special Issue, 17, 299-210.

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MacMillan, D.H. 1949. Tidal features of Southampton Water. Dock and Harbour Authority, 1-8.
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Mitchell, G.F., Penny, L.F., Shotton, F.W. and West, R.G. 1973. A Correlation of Quaternary Deposits in the British Isles. Geological Society, London, Special Report No. 4, 99pp.

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Percival, S.G. 1871. [by Spencer George Percival]. A silicified coral from the coast of Sussex etc.. Sir - Rolled fragments of a Silified Coral, resembling the Tertiary Isastraea, are occasionally found on the coast of Sussex and the Isle of Wight. Major Barnes of Southampton, who has for many years collected the south-coast agates, has found four specimens, one on the beach at Ryde, two at Sandown, and one at Hastings. I also obtained a fine specimen on the beach at Hove, near Brighton. The only locality from which they could have been drifted, if they belonged to the Oolite [i.e. Jurassic], is Portland. Does the Tisbury Coral occur there? or can they be derived from the Upper Greensand, like the silicified wood found at Hove? Spencer Geo. Percival. [See Fisher (1871).]
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Pook, S. (Sally Pook). 2000. (12 noon, 31st October 2000).
Unlucky Selsey struck by second tornado in two years.
The Telegraph (Newspaper, online).
Most people were still in their beds when the tornado appeared in the early hours. By the time it had passed, up to 200 caravans on the West Sands site had been severely damaged, some wrecked. Three people had suffered minor injuries. The caravan park had already been terrorised by the phenomenal winds that buffeted the site for much of the night. Caravans and chalets had their roofs or sides ripped off, while virtually the entire frontage of a recently completed restaurant, bar and ballroom complex was destroyed. Its giant windows, built to withstand earthquakes, were sucked out by the force. At least one caravan was lifted by the 90mph winds and dumped several yards from where it had been left unanchored, as 15ft waves battered the shore. An eight-ton children's helter-skelter had also been crumpled in the wind. Witnesses spoke of dark, swirling winds, of terrifying noises and of being unable to see in front of them as the tornado struck. It was all over within minutes, but yesterday the debris from a frightening episode was left strewn across the site. --- continues.
It was less than two years and 10 months ago that Selsey was hit by a 100mph tornado that caused damage totalling 2 million. It passed within a few hundred metres of the path of the second tornado.
Then, the astronomer Patrick Moore, 77, hid under a table at his local curry house. This time, he was in the shower. He said he was "utterly stunned" that a tornado had struck the area twice. He said: "I can't explain it. It is said that lightning never strikes twice, but clearly the same is not true of tornadoes. It makes me quite nervous to go outside." --- (continues)
The West Sands caravan park was evacuated as soon as the tornado swept in from the sea, although people were allowed to return some time later. David Strachan, 70, a retired publican from Winchester, Hampshire, had tears in his eyes as he surveyed his destroyed caravan. ---- (continues)."


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Preece , R.C., Scourse, J.D., Houghton, S.D., Knudsen, K.L. and Penny, D.N. 1990. The Pleistocene sea-level and neotectonic history of the eastern Solent, southern England. Philosophical Transactions of the Royal Society of London, B328, 425-477.
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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, vol. 2, 255-259. By Joseph Prestwich, with a plate. [contains a classic description of the Alum Bay cliff section.]

Prestwich, J. 1857. On the correlation of the Eocene Tertiaries of England, France and Belgium. Quarterly Journal of the Geological Society, London, 13, pp. 105, 115, 118-126, 131.

Prestwich, J. 1854. On the structure of the strata between the London Clay and the Chalk in the London and Hampshire Tertiary Systems. Part II. The Woolwich and Reading Series. Quarterly Journal of the Geological Society, London, 10, 75-170. [By Joseph Prestwich]

Prestwich, J. 1872. On the presence of a raised beach at Portsdown Hill near Portsmouth and on the occurrence of a flint implement at a high level at Downton. Quarterly Journal of the Geological Society, London, 28, 3841.

Prestwich, J. 1883. Notes relating to some of the Drift phenomena of Hampshire: 1. Boulders, Hayling Island; 2. Chert debris in the Hampshire gravel; 3. Elephant Bed, Freshwater Gate. Report of the British Association for the Advancement of Science, 52nd Meeting at Southampton in August, 1882. Transactions of Section C, pp. 529-530. By Professor Joseph Prestwich, M.A., F.R.S., F.G.S.    
"In this paper the author draws attention to a few points which have either escaped notice or on which he would put a different construction. 1. The remarkable boulders of crystalline and other old rocks of Pagham were noticed long ago by Mr. Dixon and Mr. Godwin-Austen; and Mr. Codrington has more recently described similar boulders in the gravel of Portsea Island. Those of Hayling Island have not yet been noticed; nevertheless they are very numerous. The author describes two of granite and three of sandstone of large size on the shore near the railway station, and states that he counted thirty smaller ones in a mile to the westward of the station. The greater number, however, of those ou the shore facing South Hayling village seem to have been collected to form rockwork in the Grotto grounds and in the grounds of Westfield House. Amongst them are boulders of granite, syenite, porphyry, slate, and sandstone. They are found scattered in lesser numbers all over the island, embedded in the flint gravel and loam which overlies London clay. Mr. Godwin-Austen considered that the Sussex boulders might be derived from an old coast now submerged in the area of the British Channel, but the author sees reason to believe that they are more probably derived from the coast of Devon and Cornwall. A large fragment of siIicified Portland wood has been described by the Rev. O. Fisher from Pagham, and the author saw in Hayling Island a piece above two feet in length of well-characterised Portland wood. The granites and other rocks, though not yet determined, seem to resemble West of England rocks, and he saw none of the characteristic granite of Cherbourg amongst the boulders. Further, the author found at Stubbington Cliff and Hill Head nnmerous quartzite pebbles similar to those of the Budleigh conglomerate. He concludes therefore that the boulders were carried here by ice at the time the old Raised beach of Brighton, Portland, and the Devon coast, and that their absence in the intermediate area is due to the destruction of the beach and the wear back of the of the old coast line, except at a few spots where, with remnants of the beach, the boulders have been preserved..."[continues]

Prestwich, J. 1892. The raised beaches and "head" or pebble drift of the south of England. Quarterly Journal of the Geological Society, London, 48, 263-343.

Prestwich, J. 1892. The Solent River. Geological Magazine, 35, 349-351.

Prestwich, J. 1892. The raised beaches and "head" or pebble drift of the south of England. Quarterly Journal of the Geological Society, London, 48, 263-343.

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Reid, C. 1892. The Pleistocene deposits of the Sussex coast and their equivalents in other districts. Quarterly Journal Geological Society, London , 48, 344-361. By Clement Reid.

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SCOPAC, Standing Conference on Problems Associated with the Coastline. East Head to Pagham Harbour, West Sussex. Available online. [Short example text below is from the introduction.]
Introduction: The coastal zone of the Selsey peninsula is an exceptionally complex environment, not least because the well-defined headland of Selsey Bill separates shorelines with different orientations (Photo1). Because of spatial variation in wave climate, and the effects of both planshape and submerged relief on the local tidal current system, the apex of the peninsula functions as a regionally significant boundary between adjacent sediment transport cells. The presence of offshore and nearshore banks, bars, shoals and reefs adds unusual complications to the sediment budgets of each of the several distinct littoral transport sub-systems. Exceptionally rapid erosion over at least the last five millennia has resulted in the submergence of both natural and human-modified coastal landscapes. This legacy has not been fully explored, but has generated considerable speculation over the sequence of coastal evolutionary changes.
At the shoreline, a partially swash aligned shingle storm ridge and sandy lower foreshore extends the length of Bracklesham Bay to the Chichester Harbour Inlet. The eastern side of the Selsey peninsula is fronted by a drift aligned gravel beach. The hinterland is low-lying, but elevated slightly at East Wittering and Selsey. At Medmerry, the hinterland is close to or below mean sea level and is formed of soft alluvial deposits comprising a reclaimed estuary channel. A weak to moderate net shoreline drift transports sediments from the east to west, although actual drift of shingle is presently very low due to the widespread controlling effects of groynes.
It is only within the last 50 years that the majority of this coastline has been protected by formal defences and regulated by other shoreline management practices. Artificial control of beach volumes and sediment transport pathways has not succeeded in achieving conditions of shoreline stability at all points; indeed, there are several critical locations where, in future, it may be necessary to allow for natural shoreline behavioural tendencies and relax management controls (Posford Duvivier, 2001; HR Wallingford, 1995, 1997; Cobbold and Santema, 2001).
[continues with 1.1 - Coastal Evolution.]

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Wallace, H. 1996. The Vanished and Forgotten Estuary of the Lavant, and its Iron-Age and Roman Port off and under the Present Selsey East Beach. Sea Level and Shoreline Between Portsmouth and Pagham for the Past 2500 Years. Part 2, Chapter 2. Pages 2-2-2 to 2-2-31. Unpublished text with figures by Major Hume Wallace (ret.). "The fact that there was a depression in the otherwise shallow seabed off Selsey East Beach, used as a summer anchorage by several hundred fishing boats and pleasure craft, was brought to our attention by air photographs in 1968, as detailed in the previous chapter, which also gives the reasons for believing that this was the estuary of the River Lavant, before that river was diverted westward through Chichester into Chichester Harbour by the Romans... Here we set out the additional evidence that it was indeed a river valley, dating back at least two glaciations, revealed by our underwater investigations which were started as soon as we had seen the photos... These investigations were usually combined with those in the Mixon gorge, which we dived at slack water two hours before low, and then on our way back to our embarkation point at the north end of East Beach, we would drift dive NE with the tide up the anchorage. By these means we built up over several years the picture of this former estuary and its remarkable seasonal changes..." [continues]...About 100 yards offshore he found the remains of Beacon House and a hollow brick pillar. The son of the head gardener of the house told him "That will be the base of the gallows tree where they hanged me grandfather, for killing a preventative man with a cutlass in the last great battle between the Selsey men and the Preventatives"... The most exciting of the finds in this [Ipswichian Interglacial] deposit came in 1957, when the erosion of the raised beach, and the modern beach derived from it, exposed a rhinoceras skeleton in pit on the low tide line, only visible at the lowest Springs, so there was a great rush to examine it and excavate it while the opoportunity lasted. [The rhinoceras bones are in the Natural History Museum. E.M. Venables interpreted the remains as those of a deadfall pit which Wallace discusses as due to Neandethal hunting. Location of a mammoth find is also given.]


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West, R.G. and Sparks, B.W., 1960. Coastal Interglacial Deposits of the English Channel. Proceedings of the Royal Society of London, Series B, 240(701), 95-133.

West, R. G. et al., 1984. Pleistocene Deposits at Earnley, Bracklesham Bay, Sussex. Philosophical Transactions Royal Society of London, Series B, 306, 137-157


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White, G. M. 1934. Prehistoric Remains from Selsey Bill. Antiquaries Journal, 14, 40-52.

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| Home and List of Webpages

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Copyright © 2013 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 cancell 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.