|Home and Contents |Field Guide Maps and Introduction | Erratics of the Wessex Coast.| | Hurst Castle Spit| | Solent Introduction| | Solent Bibliography - General | Solent Bibliography - Topics | Fawley Power Station Geology |The Geology of the Beaulieu River Estuary |The Geology of Lepe Beach |New Forest Geology |New Forest Geology Bibliography | [See also: Calshot Activities Centre.]
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Including Eagle Cliff, the coast at Eaglehurst and Calshot Spit, all at the southeastern end of Southampton Water.
1b. Introduction - Safety and Risk Assessment
1d. Introduction - Aerial Photographs
1e. Introduction,- Arrival and Car Parking
3. LOCATIONS AT AND AROUND CALSHOT SPIT
3b. LOCATION - AROUND CASTLE AND HANGERS
3C. LOCATION - ARM OF THE SHINGLE SPIT
3d. LOCATION - LOW TIDE, DARK SHINGLE BANKS
4. ROCK DISPLAYS (SINCE REMOVED)
5. FAWLEY POWER STATION (SEE ALSO FAWLEY WEBPAGE)
6. LOCATION - CALSHOT-SPIT - Subsurface Geology
7. LOCATION - ADJACENT SALTMARSHES
8b Eagle Cliff, Luttrell's Tower
9. LOCATION - CLIFF NEAR BOURNE GAP
9. Cliff Near Bourne Gap - Barton Sand and Pleistocene Gravel.
10. DISTANT LOCATIONS of the Solent around Calshot Spit
11. DEEP CHANNELS FOR SHIPS NEAR CALSHOT SPIT
11. DEEP CHANNELS FOR SHIPS NEAR CALSHOT SPIT
13. THE DEVELOPMENT OF CALSHOT SPIT (EXTRACT FROM: HODSON AND WEST, 1972)
12. BIBLIOGRAPHY AND REFERENCES
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1. GENERAL INTRODUCTION
Calshot Spit is a medium-sized shingle spit within the Solent Estuarine System. It is at the seaward end of Southampton Water. This is a low-energy location because the Isle of Wight gives protection against the open sea. As a result this spit is only about 3 metres high (excluding the heights of added building). The pebbles are of about 4 or 5 cm. in length. They are conspicuously subangular and not suffered any significant abrasion in this quiet environment within the Solent. They have come only a short distance from the cliffs of Stanswood Bay (which must have entended further seaward until about the 1500s). Unlike the much more robust Hurst Spit, this is a very local feature, of local derivation. It is post-Neolithic and the present spit has formed in an extremely short time, perhaps only between 500 and a thousand years. It became more strongly developed, but not longer, after King Henry VIII's castle was built. It is distinctly a modern feature of a modern coast.
The spit has been developed first as a defensive site (against the Spanish). Later it became a seaplane base. Now it is mainly used for tourist puposes and sporting activities. It is urbanised and you can drive a car almost to the end of it.
The fresh, subangular, ex-Pleistocene, light-brown, shingle of the spit (i.e. the local ex-cliff material) is all above low-tide level.
The Great Storm of 1703 (described by Daniel Defoe) undoubtedly had a severely damaging effect in this area (lateral blowing of chimney pots at Christchurch etc; New Forest trees blown down). This might have caused increased erosion in the pebble supply area of Stanswood Bay. Not too long afterwards, in 1775 the Calshot Spit was hit by the tsunami of the Lisbon Earthquake. However, the wave height was not very great, perhaps not much more than the 3 feet (roughly 1 metre) level reported at Portsmouth (in the harbour?). The tsunami was not, of course, a single wave but a phase of wave action which lasted for several hours. It is not known whether the storm of 1824, which flooded over the Chesil Beach had much affect in this relatively sheltered area.
The great Bray Fault (or Bembridge - St. Valery Fault), trending SE-NW across the English Channel (La Manche) and enters the land area near Calshot Spit. This is an old deep thrust fault, dating back to the late Palaeozoic. Its exact site is uncertain and it is sometimes regarded as being under Chichester, rather further east. [see the associated webpage on "Oil-South-of-England, for details]. Earthquakes can very occasionally reach the intensity of 6 in the region and Glastonbury has supposed to have ben damaged by a "Chichester Earthquake" - although most are small. Minor local effects of a "Chichester Earthquake" has been oscillation of water in a well at Marchwood, not far away. The Bray Fault does not often move, but is distantly connected with the anticlockwise rotation of the Pyrenees [the opening of the Bay of Biscay has been affecting southern England for about 145 million years, - but that is another story!]. So, at Calshot Spit, tsunami waves are not very likely occurrences, and because of the sheltered environement, less so than at Hurst Spit (occasionally hit by smallish tsunamis).
So, in all, the risk at Calshot from earthquakes and great storms is not usually great within the very short lifetimes of individual human creatures, but, of course, the rare possibility cannot be completely eliminated. If the Bray or St. Valery Fault was to suddenly move violently then some effects could occur in this Hampshire area.
There is a specific matter regarding the pebble deposits of Calshot Spit.
More complicated and less easily explained than the high shingle, is an older darker shingle (or gravel) seen at very low tide. This is overall, dark brown in colour. Striking feature is that it is very poorly sorted and it contains many large and rounded pebbles. It has not had the sorting by longshore drift that the upper, light-brown shingle has. This had a quite different origin. There is also much older gravel directly beneath Calshot Spit, as had been shown by boreholes. See the associated Fawley Power Station webpage.
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1. INTRODUCTION:
1a - Access
Calshot Spit is easily reached by driving southeast down the B3053 on the western side of Southampton Water past Fawley Oil Refinery and Fawley Power Station. There is some free parking at Hillhead (the landward end of the spit) and there is pay and display parking further to the northeast, at the beginning of the spit, about halfway down and at the Calshot Activites Centre at the end. There are toilets and a cafe and bar (open at times) within the activities center. Most of Calshot Spit is directly accessible on foot. Part of the beach to the southwest towards Eaglehurst is accessible. However a short distance beyond Luttrell's Tower there is a nature reserve with no public access. Unless permission is obtained, there is no direct access to the best cliff sections. They can be seen at a distance.
1 - INTRODUCTION (CONTIN):
1b - Safety and Risk Assessment
Except in unusually stormy weather conditions this is not, in general, a locality of high risk to anyone studying geology or geomorphology. However, there are some potential hazards. Obviously be very cautious if visiting in extreme weather conditions. Activities taking place at the sport centre in the old hanger on Calshot Spit are not in any way connected with this website or have any responsibily connection with this website. Calshot Castle is a specific, separate location for which you pay a fee to visit, and this website is not connected to this and does not have any responsibility regarding it.
There might be some small risk of falling debris from the low cliffs in places. However, there are no high, vertical cliffs here, so that this is not a major problem.
Anyone venturing into the adjacent marshes could become very quickly stuck in soft mud. This is a real risk. Once stuck in the mud, it would be very difficult to get out.
There is a strong current at times in the sea at the end of the spit. Entering the sea should only be in safe localities, well away from the distal areas with high current velocities and with shipping. This is just common-sense.
Beachhut are not in any way connected to this website except as convenient level markers. In many cases the huts are situated at almost exactly the level of the top of a storm beach and not significantly higher than the rare limit of extreme storm wave activity. The are only referred to regarding their relationship to changing beach levels (they are useful markers) and the observation than some or many may not be above the limit of future extreme storm activity (of course, the beach and these should be strictly avoided during a hurricane).
Please respect private property. To the southwest is the major Cadland Estate and most of this is private and not accessible to the public. There is a barrier at a short distance southwest from Calshot Spit. You cannot walk on the shore from Calshot to Lepe Beach. However, a short drive round the lanes will take you to Lepe Beach where there are car parks and easy access to the shore.
1 - INTRODUCTION (CONTIN):
1c - Historic Maps
The interested reader should purchase the current topographic and geological maps of the area, and probably the Admiralty Chart. Any redrawm maps here are only intended to be introductory and they are outdated, even historic, and not guaranteed to be accurate and not showing the current topography or necessarily the current geological interpretation. They are unsuitable for research or detailed studies or navigation. No responsibility is taken for misuse of these old maps. The new land map is easily obtainable from the Ordnance Survey and the geological map from the British Geological Survey and they should be purchased from these sources.
On the old, 1893 (but surveyed earlier), geological map, of which a small part is provided above, Calshot Spit is shown long before the development of Fawley Power Station. Note particularly the Barton Clay and Barton Sand outcrops nearby, the originally-greater extension of the estuarine alluvium, and the (in purple) Pleistocene gravel on the high ground. It is believed (in 2018) that it is possible that the construction of new houses might take place somewhere in the area. Thus, this map might be useful for very general, approximate, but not necessarly precise, identification of underlying bedrock or Pleistocene or Holocene strata beneath (there is also made ground, and a pipe-discharge area). In addition, there are many records of shallow borehole here (many collected by me in the 1950s and filed for reference in the Southampton University, NOC library). The numerous shallow boreholes are the result of studies for the constuction of Fawley Power Station. Not shown and not existing, of course, when the original geological mapping took place are two tunnels under this area (they were mostly steel encased, but may have concrete walls in places). One is the Fawley Transmission Tunnel, steel and carrying electricity cables across Southampton Water and the other one is the Outfall Tunnel heading out to an outfall structure (in Barton Clay) in the Solent. Incidently one of the re-surveyors in the old geological mapping of this Lymington Sheet was Aubrey Strahan (later well-known as Sir Aubrey Strahan, Director of the Geological Survey).
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1d - Aerial Photographs
1 - INTRODUCTION (CONTINUED):
1. INTRODUCTION:
1e - Arrival and Car Parking
Car parking is usually easy at the landward end of Calshot Spit, and it is rarely much of a problem in other parts. The car park at the end of the spit at the old RAF base is quite large (the area was presumably used for parking seaplanes). The car parks are based on shingle. That on the outer, southeast side is coarse beach gravel. There is fine gravel on northeast, marsh side is finer. It seems to be replaced in part from time to time, from an artificial gravel tip near the life-boat house.
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2a. HISTORY OF CALSHOT SPIT - GEOMORPHOLOGICAL SIGNIFICANCE
Calshot Castle is important in terms of geomorphology because it is a marker point showing a coastal position from about 1540. It was built on the orders of King Henry VIII, using stone derived largely from Beaulieu Abbey which he had destroyed. The Bembridge Limestone, present in the castle, is probably of this origin. Calshot Castle can be compared to Hurst Castle on Hurst Spit as both were build at about the same date, and are broadly similar. Hurst Castle is not at the end of Hurst Spit now. The reason is that that spit has extended appreciable beyond it because there has been dramatic erosion in Christchurch Bay since 1540. Indeed, the original village of Hordle, above the original Hordle Cliff, has been destroyed by coastal retreat and a new village build further inland. There has been less coastal change in the Solent coast near Calshot Spit.
In 1611, there was a deficiency of shingle in the middle to landward part, as shown in the map above. Go to:
Buhler (1952).
[Extract, p. 249: "This Breache beinge a thinge muche to be respected for that if it is not repayred, there willbe shortlie no passage without boate, to or from the Castle - as yet there is passedge for horse and man at a low water, and it will coste the repayringe, either with stones or claye (but I take clay the surrest and fitteste) with some ayde of the Countrye whom also it doth much concern about - "
"There must be wood allowed out the foreste, to make a defensive hedge agaynste the violence of the sea while the work is in hande, according as occasion shall require."
By - J. Norden [John Norden, His Majesty's Surveyor]
Later, the great 1703 hurricane added much shingle to the spit, this probably having come from the Stansore Point area, but did not change the position of the end of Calshot Spit much. The northeast end was probably appreciably broadened, provinding the flat surface that was much later used for the aircraft hangers.
Clare and Fred Murley (1991) recorded (on p.24) the comments in 1695 of the traveller, Celia Fiennes. She wrote:
".. about 3 leagues off is Calshot Castle just out into the sea, which does encompass it all but a very little point of land called Horsey Beach that runs out into the New Forest by Bewly which was an Abbey in the Forrest, for the extent of the Forrest is large miles long: all round Calshot Castle on the beach itts as full of fine Cockle shells ["Cardium" or more strictly, Cerastoderma - now still common but perhaps not so abundant] so they heap them up all round the castle like a wall; ...."
The modern Cerastoderma shells are present in white, shell beaches, normally at the outer parts of salt marshes. They are best developed where there is little or no supply of flint shingle. They are easily seen on aerial photographs. Nowadays you will find these on the up-estuary side (northeast) of Calshot Spit, but I do not think that there is such abundance as to be able to heap them up round the castle. Old buried examples of such Cerastoderma shell beaches were found when the excavations were made for Fawley Power Station.
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2b. HISTORY OF CALSHOT SPIT - RECENT
History, Recent - LAWRENCE OF ARABIA AND THE NARROW GAUGE STEAM TRAIN
The end of Calshot Spit was in the early part of the last century an RAF base used for various seaplane experiments. The most notable person who worked here was Lawrence of Arabia. He was, apparently, just an ordinary, low-ranking aircraftsman who worked at this base. Photographs above relate to the narrow gauge railway from the camp site on the hill near the cliffs, to the end of Calshot Spit.
3. LOCATIONS AT AND AROUND CALSHOT SPIT
Calshot Castle, built for King Henry VIII in about 1540, is a good marker for showing the changes in Calshot Spit. The present spit is very much a feature, greatly modified by the hurricane of 1703 and probably not changed much in outline, since then. It is unlike Hurst Spit which formerly was growing, before various artificial coastal obstructions at Milford-on-Sea and Barton-on-Sea severely damaged it. Calshot Spit is not normally exposed to large sea waves and thus is much lower than Hurst Spit. The castles of the two spits are broadly similar. There has been minor retreat of the coast at Calshot Castle so that there is no high-tide shingle directly in front of it (the sea also just approaches the walls of Hurst Castle).
The blocks of limestone in Calshot Castle can be identified in some cases, but in others the surface conditions and the weathering does not make this an easy task. Most conspicuous and most easily identified is Purbeck Stone from the Middle Purbecks of Durlston Bay, or adjacent area, Swanage, Dorset.
Very obvious to the geological visitor is a very, early-cemented, biosparrudite from the Middle Purbecks of east Dorset (Durlston Bay to Lulworth Cove). Cross-sections of the bivalve Neomiodon are obvious. They are almost entirely uncompacted. Compare the limestone in the castle to the uncompacted, early-cemented type of Middle Purbeck limestone from Bacon Hole, shown above. It is not implied that the rock is from Bacon Hole, but it is this type of limestone from the area between Lulworth Cove and Durlston Bay, Swanage (a more likely source locality).
A notable absence in the blocks examined is Praeexogyra distorta (J. de C. Sowerby). This absence eliminates certain horizons, particularly those above the Cinder Bed [P.distorta is less common beneath].
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A further point regarding Purbeck Stone is that at Lepe Beach, not far away to the southwest, a dinosaur footprint in Purbeck Stone has been found on the low-tide beach [see Lepe Beach webpage]. This too, is probably in the uncompacted, early-cemented type of Middle Purbeck limestone. Blocks of Purbeck Marble (from the Upper Purbeck, or uppermost Durlston Formation) from Peveril Point, Durlston Bay, Swanage or nearby have also been found at Lepe Beach (see Lepe webpage).
Bembridge Limestone blocks can be recognised by the scattered gastropod shell remains found in shell moulds (holes). These shells seem to be still preserved as aragonite. This limestone is relatively soft. It is, of course, very near at hand, occurring just across the West Solent on the Isle of Wight.
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It should be noted that a complication regarding the stone at Calshot Castle is that it is largely reworked from the destruction of Beaulieu Abbey by King Henry the Eight, who ordered the building of the castle.
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This distal end of Calshot Spit has been greatly altered above the shingle by human activity. Apart from the castle and a tower to control shipping, the huge RAF hangers are the main features of the end of the Spit. Around the margins of the altered area it is quite easy to access the shingle, particularly at low tide. Many people, especially young people come to visit the sporting facilities, including cycle racing, climbing and dry skiing in the big Sunderland Hanger. There is also a cafe in this building. Calshot Castle, built as one of a series of coastal protective castles for King Henry VIII, is a very different type of building. It has limestone rock walls of particular interest to geologists, and various features of historic interest. It has guns and it gives a good view of ships entering or leaving Southampton Water.
At two sites, one at Lawrence House, a brick building and the other at the Sports Hanger on Calshot Spit there were (until 2018) on display, large blocks of hard rock, probably quartzite. I do not know the origin of these, but they resemble sarsen stones, which occur commonly in the area [they have since been removed].A sarsen stone is present now on the beach at Eagle Cliff and sarsen stones are washed out of the cliff on the opposite side of Southampton Water at Chilling and Brownwich Cliff.
See the websites:
Chilling Cliff, Brownwich Cliff and Hill Head (opposite shore to Calshot)
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3C. LOCATION - ARM OF THE SHINGLE SPIT
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The main arm of the shingle spit is a narrow shingle beach. On the marsh (northwestern side of this), a narrow road has been added to give access to the end of the spit, the former seaplane base, the big hangers and now the sports facilities, within one of these hangers. Some brick buildings are also relics of the former air force base.
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At the midway location (and small car park) on the arm of Calshot Spit there is, as at Eagle Cliff, obvious evidence of natural raising of the top, back beach and the partial covering of groynes. A southwest to northeast movement of shingle is also shown. It confirms the simple theory that in recent years the Bourne Gap area is eroding and supplying shingle, whereas, in contrast, and the general shingle drift that is taking place northeast of Bourne Gap is towards the end of Calshot Spit and the top of the beach at each site. In summary Bourne Gap is a retreating supply area and Calshot Spit is gaining shingle and rising in height. The only, at first sight, surprising aspect of this is the height rise. Although sea-level is rising and this is one factor, a more important one may be the occurrence of the 1 in 60 year (roughly) storm in 2014. That seemed quite a major storm but it was nothing like the 1 in 250 year storm of 1824 or the rare, great hurricane of 1703, that completely changed Calshot Spit. Hurst Spit is intermittantly washed flat (at least in the central) because its shingle supply has been cut off by artificial sea defences at Milford-on-Sea. It has not been permanently destroyed as yet, but the main shingle bank (beyond the larvikite rock armour) probably will be sooner or later. This will, of course, cause a major increase in coast erosion in the West Solent. This is a familiar story and does not further elaboration here. The consequences of this or related major events is an increase in shingle supply to Calshot Spit. It may be flooded but it is unlikely to loose much shingle; it will probably gain substantially. Erosion and losses might be expected at Stone Point and Stanshore Point Lepe. If a large shingle supply from there sweeps northeast it could go past Bourne Gap without causing too much loss of land and travel on to an enlarged Calshot Spit (which, of course, is the terminal spit and shingle-dumping area for the West Solent. Much of the West Solent coast will retreat and straighten in one or more great storm, the Beaulieu River mouth may or may not be closed by shingle (quite likely) and Calshot Spit will enlarge as the terminal shingle dumping ground.
(Solent - future. There is no suggestion here that the natural processes of reshaping and opening up the West Solent coasts are necessarily going to take place in the lifetimes of existing people; it could be in 250 years and the chances of it happening next winter are low. The English Channel or La Manche can be viewed in term of thousands of years is an expanding sea, at the moment in its second recent pause, but warming up again now. Of course matters may change and a Neolithic-type low sea level or still-stand happening again is only very unlikely and is not totally impossible.)
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Observe the interesting aspects of this area. The pebbles are almost completely unrounded; they are just as eroded from the Pleistocene gravel of the cliff, and have original yellowish stains. Regarding size, they are small to medium, never large, and are very well-sorted in terms of size. The most surprising feature of the pebbles is the small size and this is presumably the result of Calshot Spit being in a relatively sheltered area (although waves of limited fetch can come in from the southeast). It is good for the spit (probably essential) that there is some re-supply of shingle coming from the low Solent cliffs to the southwest (between Calshot and Lepe Beach). As sea-level rises, resupply from this area will become increasingly important.
It may be that part of Calshot Spit is in a sense "fossil" and not fully adjusting to rising sea level. Is the spit surface (at least the end, tarmacked part) really at historic dates (of Henry VIII or Lawrence of Arabia?). No detailed study of this has been made here, and there is no suggestion implied that it is in the potential, partial failure state of Hurst Spit. Of course, it is likely to last a significant time in human terms, but some rare sea-flooding and/or change of shape at some time in future might be discussion points. Of course the spit is mobile and it will move and change in geological time. The Solent Estuarine System is an expanding system and some coastal retreat is normal. As the West Solent slowly expands the spit should naturally adjust.
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The flint pebbles of Calshot Spit are subangular and have not been rounded by abrasion on the beach. This lack of rounding is presumably the result of very limited wave action, something that is confirmed by the low level of the top of the beach above sea-level (only about 3m.). In other words, it is very different from the Chesil Beach, Dorset. The sorting is notable though; large pebbles as are present on the beach of the cliffed area of Stanswood Bay but these are absent at Calshot Spit. Presumably the small waves that characterise the West Solent cannot move the large pebbles to the spit.
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3d LOCATION - LOW TIDE, DARK SHINGLE BANKS
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Offshore from the main shingle bank of Calshot Spit, and seen only at completely low tide, are firm, dark banks of poorly-sorted pebbles. These are peculiar because the pebbles are poorly sorted and frequently much larger than the 4 to 5 cm. pebbles of the main Calshot Spit. More remarkable is the fact that these dark pebbles are often very rounded, quite unlike the uniformly subangular pebbles of the main shingle bank. They have not come from the bank, but represent a deposit of different origin. They have been subject to much more severe abrasion and seem to have been in a relatively high energy setting, in terms of wave action.
Since the large pebbles have obviously not come from the present bank, what is their origin? They are not unlike the rounded, pebbles of the Pleistocene, Portland raised beach. It is strange that these pebbles have received substantial beach-battering, whereas the modern beach pebbles of the main bank of Calshot Spit show almost no effects of abrasion on beaches.
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4a. LOCATION - ROCK DISPLAYS AT THE END OF CALSHOT SPIT (now removed!)
[N.B. By August 2018, unfortunately, these interesting rocks seem to have been removed. I do not know where or why they have gone.]
Near the end of Calshop Spit there are two displays of large rocks. These are angular or partially rounded, apparently of quartzite and they resemble sarsen stones.
Sarsen stones occur in the area, and elsewhere in this webpage there is reference to one at Eagle Cliff. They are more abundant in the Titchfield, Chilling and Browwich region across Southampton Water, and from time to time they are eroded out of the cliff there.
For more information go to:
Chilling and Brownwich Cliffs Webpage. [run down to the Sarsen Stones section]
In that area though the sarsen stone quite often contain root holes left from the former presence of plants. These do not seem obvious in the stones at Calshot Spit, which are now shown below.
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5. VIEWS - FAWLEY POWER STATION For more information on Fawley Power Station geology, go to the webpage on:
Only a few views of this large Power Station nearby are shown in this particular (Calshot Spit) webpage.
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From the narrow road down the shingle spit there is a view to the northwest of the Fawley Power Station. This was no longer in use in 2017; there were plans to demolish and build a housing estate. A photograph of the empty building in November 2020 is also shown above.
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6. CALSHOT-SPIT - Subsurface Geology
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The maps and cross-sections above come from a study by the present author, years back before the Fawley Power Station was built. There were deep excavations in soft mud, descending well below the Neolithic peat. It was not an easy place to work. There were huge cranes. The driver of one of these chased me around part of the site with the huge bucket swinging towards me and following as I waded in the mud of the site. Going into the pressurised tunnel required a doctor's examination first. Down under Southampton Water the main danger was that the workers were in a great hurry and you were in considerable danger of being run over by the tramway trucks. There were other risks. Sadly one worker was killed when a sealing door was not completely shut and he was blasted through the opening by the high pressure.
I was called in when there were geological problems. The cross-sections probably do not show a small fault in the Eocene strata, somewhere near the middle of the tunnel. Eocene faults are actually unusual in the region , but Southampton Water has a major fault beneath it in older strata, and there may have been minor re-activation in the Tertiary.
More specifically, geological study of the above diagrams suggests that Calshot Spit has been in approximately the same position for a very long time, perhaps since at least Neolithic times. This will be discussed further.
[further information on the geology will be added]
For more information go to the related webpage:
Geology of Fawley Power Station,
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7. LOCATION - ADJACENT SALTMARSHES AND CHANNELS
For Saltmarshes see also:
Fawley Power Station - geology.
See also:
The Geology of the Beaulieu River Estuary.
For more information on Solent saltmarshes go to:
The Geology of the Beaulieu River Estuary
and
Solent - Geology of Fawley Power Station
and
Solent - Lymington, Keyhaven and West Solent
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8. EAGLE CLIFF (a former habitat of the Sea Eagle, or White-Tailed Eagle)
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8a - EAGLE CLIFF, STANSWOOD BAY - General
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The landward connection of the Calshot Spit shingle beach is to Eagle Cliff. It is now at a short stretch of beach huts. The cliff has degraded is not a steep eroding feature now. It is just an overgrown bank, at 45 degrees, and with many trees. There has been considerable shingle accumulation in the 1703 storm and probably since that date this has prevented significant cliff erosion here. Historic details of the steps down from Luttrell's Tower show that nothing much has happened here since about 1740 except the growth of trees on the old cliff. (The trees are probably the Holm Oak, Quercus ilex, an introduced Mediterranean tree that grows well on the mild, south coast of England.)
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Eagle Cliff and nearby Eaglehurst, were probably named after the former habitat here of a White-Tailed Eagle, or Sea Eagle. This huge eagle, which still survives on the Isle of Mull, ate fish and probably scavenged beaches in the local Solent estuaries. It was presumably here before the coast was changed by the 1703 hurricane, and before buildings such as Luttrell's Tower were constructed here.
See also:
By Derek Y. Yalden.
Yalden, D. 2007. The Older History of the White-tailed Eagle in Britain. By Derek Y. Yalden.
This does not seem to mention the Sea Eagle of Eagle Cliff, Calshot, even though the eagle symbol is used at the present time by the Cadland Estate (at the southwestern end of Eagle Cliff). The name of the place Eaglehurst, on the land above the cliff, ties in the reference of the bird to an old name for a spit ("hurst", as in Hurst Spit). At the time the bird was hunting for fish here, Calshot Spit was a lesser, poorly-developed feature in mudflats and marshes. At the time, the West Solent shore, here, was probably a very quiet, remote coast at the seaward margin of the New Forest.
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There is a new notice board, placed there by the New Forest District Council at the path where it enters the beach, at the southwestern part of Calshot Spit. Nearby is an old metal sign from 1932, regarding the privacy of the Cadland Estate. This is a bird nature reserve, but now lacking any sea eagles.
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The cliff is part of the extensive Cadland Estate, as is shown on the old notice, by the beach huts. The beach is accessible southwestwards to a modern, timber barrier, about three quarters of a kilometre from here. Modern notices will be found there. The metal one, by the beach huts, shown here is old, half-buried in shingle and, unfortunately, it seems to have been rather ill-treated. It is from 1932 and is of historic interest (thus, perhaps it needs raising from the shingle, given a cautious cleaning and retained on public view in perhaps a better location nearby).
Within part of Stanswood Bay, the Hill Head or Hillhead area is of interest. The shingle beach is well-developed here. The back cliff is of Pleistocene gravel over Barton Sand, but it is mostly rather degraded and overgrown (trees grown on it to the southwest). As shown, elsewhere in this webpage, there is evidence from an old metal notice that the shingle beach top has risen in height since 1932. A rather optimistic method of placing beach huts seems, at first sight, to have been adopted here. They seem to be based not much higher than the top of the shingle beach. This implies that seawater could reach them in the greatest storms. It is possible that the bases of the beach huts were once placed above the top of the beach and that the beach has risen? Or has some calculated risk been taken? The matter seems strange but it is not well-understood here. Presumably the implication is that if any future storm exceeds the highest previous one (which built up the beach) then the beach huts might be liable to be hit by wave action (at the maximum wave height). In other words, is there an adequate safety margin? No real research has been made here so this is just a question. Are the beach huts sufficiently raised above maximum beach height and maximum storm wave height? They may be, but it is a valid question because the huts seem to be not far above top beach height; more information might be useful. I will look at them again in case I have misunderstood.
8b, EAGLE CLIFF, Luttrell's Tower
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Luttrell's Tower with steps to the beach down an old cliff has survived in this location since the 18th century. This is a remarkably stable marker point. It is probable that it was built shortly after the large-scale drift of shingle northeastward from the Lepe Beach area during the hurricane of 1703. This shingle, onshore and offshore, have protected the site and the old relict cliff. There has been no new erosion here, but further east at the Nature Reserve there is active erosion of the cliff at the present time (see the section on the Eocene and Pleistocene deposits there). So Luttrell's Tower is an important fixed point, useful in determing the history of this coastline. The tower and Calshot Castle have both survived very long periods of time, but the castle is older (16th century).
[Historic note: Luttrell's Tower or Eaglehurst is at Stanswood Bay, near the eastern end of the cliff line. It rises 110ft (34m.) and stands above the 30ft (9m.) high Eagle Cliff of Eocene strata overlain by Pleistocene gravel. It was built in the mid 1700s by Temple Simon Luttrell, son of the Earl of Carhampton. It has cellars beneath and formerly a tunnel running to the beach. The Earl of Cavan lived in the house at one time.
For a series of excellent photographs of the Tower and the Eaglehurst Estate see the following, highly recommended, website:
A holiday home fit for a queen! Country estate that caught the eye of Queen Victoria and was once home to radio pioneer Marconi goes on sale for 6.5 million pounds. (Daily Mail, online. By Lizzie Edmonds, 23rd July 2014.)
Much later, in 1906 Guglielmo Marconi had a laboratory in the top room. On the morning of the 10th April, 1912, Marconi, his wife and daughter, Degna (only four year old) climbed the tower with her mother and looked out at a ship sailing past to the sea. The top of the tower was higher than the deck of the ship. It was the Titanic, almost certainly using the West Solent route out. The ship was carrying an old, obsolete radio system of Marconi, devised in 1897, which had been installed only weeks before the disaster. So Mr Marconi saw the ship with his system on board sail past his laboratory at the tower next to the West Solent. It was much later, in 1927, that Marconi laid a wreath at a small Battery Park memorial, New York city, for Jack Phillips, the wireless operator who had gone down with the Titanic, still sending out distress calls to the last. Degna, in later life commented that she, at the age of four, waved to the people on the Titanic and they waved back. However if you now sit at the cliff next to Luttrell's Tower and look at passing ships you will see that they are too far out in the mid-channel of the West Solent to see people easily, if at all. The Titanic would have been a large but fairly distant ship when it was observed from here. Incidently, it would not be surprising if it took the more-direct West Solent Channel; in contrast, the large cruise liners of today normally take the deeper southeastern channel past Portsmouth (some smaller ships go west).
Re Marconi, see
Revolutions in Communication. Media History from Guttenberg to the Digital Age. - Radio and the Titanic, By Bill Kovarik]
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See particularly: Clare and Fred Murley (1991); section on Luttrell's Tower.
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Here, near Luttrell's Tower there are the remains of some concrete platform at the base ot the cliff. Down the slope, at low tide there is some old, rusting metal work. It is too broken and rusted to be sure, but it might, perhaps, be the remains of some type of winch for pulling up a boat near the tower. Notice, at the degraded, sloping relic of the cliff the numerous Holm Oak (Quercus ilex) trees, a Mediterranean tree, probably favoured by the mild climate of this southern England coast. These tree are present all along the old degraded slopes of Eagle Cliff.
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8c - EAGLE CLIFF, STANSWOOD BAY - SARSEN STONES
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See also:
Erratics and Sarsens of the Wessex Coast webpage.
A single sarsen stone has been observed on the beach seaward of Luttrell's Tower (Eaglehurst). Since the cliffs are not retreating just here and the tower has been in existence since about 1730 it is likely that the sarsen has been on the beach for 300 years or more. It is of the large tabular type that is common at Chilling Cliff, Brownwich Cliff and elsewhere to the east and southeast. However, it has been much eroded by the abrasive action of beach shingle. It a relatively soft sarsen that is easily broken with a light hammer blow.
The sarsen has presumably come from the low gravel terrace deposits which are present in the cliff. They are at a similar level to the Terrace 2 gravels of Chilling Cliff and Brownwich Cliff. Some of the place names in the area include "Stone". In some cases this may refer to flint pebbles, but perhaps some are references to sarsen stones.
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[beach pebble photographs to be added.
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9. LOCATION - BOURNE GAP, ERODING CLIFF.
(BEYOND, SW OF, EAGLE CLIFF)
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A stretch of coast at the southwestern part of Stanswood Bay is private land, a Nature Reserve, and part of the Cadland Estate, and with no public access. There is a substantial timber barrier that extends down to low water mark. Do not try to enter. Beyond the barrier there is a low, eroding cliff of Barton Sand overlain by a Pleistocene gravel terrace. The Pleistocene deposits are very unusual for this region, in that there is almost as much sand as there is gravel present. The most probable explanation is that there was originally a river-cliff of Barton Sand close by.
The reason for the presence of cliff here is that there is normal marine erosion, with a slowly rising sea level, and very soft non-resistant strata present. From here to the northeast there is a large accumulation of flint shingle, both onshore and offshore, supposedly transported here in the great storm of 1703. This provides protection in the direction of Calshot Spit. There is no great accumulation at Bourne Gap and its vicinity, so therefore the cliff is more vulnerable.
It is possible to photograph these cliffs with a telephoto lens, from the barrier or perhaps with a boat, but without attempting to enter the area. The geological features are unusual, particularly in the Pleistocene gravel, but they cannot be examined close-up. Some enlarged distant photographs,shown below, might be of use. Some images have been corrected for obliquity by processing on-screen.
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The lowest photograph above was taken of the Bourne Gap area of Stanswood Bay in 2010, from the D-Day, Casion, construction area northeast of Stansore Point. It appears to show the Bourne Gap area without significant cliff erosion. However, caution is needed because some Google Earth photographs suggest that it had already taken place to some extent by this date. The problem is that the photograph above does not show the Bourne Gap shore far enough to the southeast, to be sure of the situation. There is some uncertainty here and more data is needed (the location is private and there is no access).
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For a stretch around Bourne Gap in the southwestern part of Stanswood Bay there is a short stretch of good cliff exposure of Barton Sand overlain by a low terrace of Pleistocene gravel. This is within a private estate, the Cadland Estate, which is also a Nature Reserve. It has no public access. The Barton Sand is present as yellow, oxidised sand in a small, but vertical, cliff. Above it is the Pleistocene gravel deposit is unusual. Although elsewhere this deposit is almost entirely of gravel, here it is very sandy and it shows much depositional lamination.
Further to the northeast, the Chama Bed, at the base of the Barton Sands, has been seen in the 1960s at the Fawley Power Station outfall in Stanswood Bay, near the beginning of Calshot Spit. It is a sandy clay that does not, just here, contain abundant Chama. It is, instead, very rich in small oysters.
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9. DISTANT LOCATIONS OF THE SOLENT, SEEN FROM AROUND CALSHOT SPIT
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10. DEEP CHANNELS FOR SHIPS NEAR CALSHOT SPIT
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Ships passing near Calshot Spit have to keep to the main, deep channels. These are sea-flooded river valleys. Adjacent to these channels are areas of former land, that has been flooded to only a shallow extent. The Brambles Bank is the most notable; occasionally part of it dies out (and a cricket match is traditional played there on occasions). Sometimes, as shown above in an example from 2015, ships are trapped on the Brambles Bank.
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12. DISTANT LOCATIONS OF THE SOLENT, SEEN FROM AROUND CALSHOT SPIT
[to be added. work in progress]
13. THE DEVELOPMENT OF CALSHOT SPIT (EXTRACT FROM: HODSON AND WEST, 1972. Holocene Deposits of Fawley, Hampshire, and the Development of Southampton Water) Proceedings of the Geologists' Association, vol. 83, part 4, 1972, pp. 421-442.
The Development of Calshot Spit [extract from p. 435]
Boreholes [fig.3 in the paper] show that the initially deepest part of the drowned valley of Southampton Water lies beneath Calshot Spit at the entrance to the estuary (Fig. 7). The spit, formed by longshore drift of beach material from the west, has apparently forced the deep channel of the estuary eastwards. It has provided sheltered water on the west bank for the deposition of thick Holocene mud deposits (Figs. 1 and 7).
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[END OF RE-ORGANISED WEBPAGE]
12. BIBLIOGRAPHY AND REFERENCES
Please go to the:
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Copyright 2020, Ian 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 the source is acknowledged.
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The eastern end of the spit is abrupt and, although artificially steepened by dredging, is probably mainly controlled by equilibrium between the supply of material by longshore drifting and erosion by tidal scour. The continued existance of the castle, built at the end of the spit in the early sixteenth century, suggests that the spit is a stable feature [however, Hurst Spit has a similar castle, but it is not stable at present]. Boreholes, however, show that the recurved tip of the spit has at times extended further to the north-west than at present. Two former extensions reached the mouth of Ower Lake (Fig. 3) and the younger of these may be responsible for the northward deflection of that creek.
Marine gravels and sand lie beneath the spit to a depth of about 17.5m. below OD. These spit deposits presumably originated by longshore drift and therefore, were formed mainly in the intertidal zone. Thus any particular spit deposits must be of approximately the same age as any adjacent intertidal estuarine mud at the same depth. This suggests that Calshot Spit existed at its present locality from Atlantic times [Atlantic period - about 8,000 to 6,000 BC]. Deep foundations have similarly been found beneath many barrier islands in the Gulf of Mexico (Shepard, 1960) where such coastal barriers were also stable during slow submergence.
Calshot Spit was reported to be in a breached condition in 1611 (Buhler, 1952) not long after the Chesil Beach had been broken through by south or south-easterly storms (Arkell, 1947). Rapid natural repair probably occurs after breaching, otherwise extensive erosion of the Fawley Holocene muds would have occurred.
The long persistence of the spit is probably due to the relatively steep slope of the Pleistocene river valley on the west side of Southampton Water at Calshot. Thus as sea-level has risen the spit has easily remained in contact with the new shore line and the supply of sediments by longshore drifting has been unhindered." [continues with: 7. Conclusions - Origins of Southampton Water.]
Ian West, M.Sc. Ph.D. F.G.S.