West, Ian M. 2013. Geology of the New Forest National Park. Internet field guide. http://www.southampton.ac.uk/~imw/New-Forest-Geology-Guide.htm. Supplement to: Geology of the Wessex Coast. version: School of Ocean and Earth Science, National Oceanography Centre, Southampton University, 17th December 2013.

Geology of the New Forest

Ian West,

Romsey, Hampshire

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

Southampton University,

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

|Home and List of Geology Webpages |New Forest Geology Bibliography |Solent Geology Bibliograpy - General list |Solent Geology Bibliograpy - Topics |Beaulieu River Estuary |Calshot Spit and Stanswood Bay |Lepe Beach and Stone Point |Solent Introduction |Barton-on-Sea - Geology |Hordle Cliff and Milford-on-Sea |Lymington-Keyhaven Coast |Hurst Spit |Petroleum Exploration, South of England

Click here for the full LIST OF WEBPAGES

A general view of Hasley Hill, New Forest, Hampshire, from the Dockens Water valley, 7th December 2008

Pleistocene Gravel Terrace 6 at Deadman's Hill, southeast of Dibden Bottom, New Forest National Park, Hampshire

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




The New Forest National Park is an important area of heathland and forest near the south coast of central southern England. It was established as the King's hunting forest shortly after the Norman Conquest in 1066. Being an unusually extensive, open, semi-wild area in an agricultural and developed part of the country it is now of very great value for recreation, conservation, wildlife, grazing of ponies and forestry. In terms of geology, the New Forest National Park is underlain by Eocene sands and clays, often very fossiliferous with sharks' teeth, molluscs and corals. There are good exposures on the coast at Barton-on-Sea and Hordle Cliff. However, inland, within the New Forest heaths and woodland the clays and sands are poorly exposed. The strata are mostly weathered and unfossiliferous at the surface. Only occasionally, and at a few places in stream beds or artificial excavations, are the Eocene strata well-exposed. Ferruginous (chalybeate) springs emerge from oxidising pyritic and glauconitic sediments in places.

Subangular flint gravel terraces of Pleistocene age lie above the Tertiary strata. The tops of these brown subangular flint gravels are usually whitened on the heaths by the development of podsol soil profiles. The Pleistocene gravels are more frequently seen because they have been much quarried in the past for road and construction purposes. Peat is developed in boggy valleys but is not longer dug and therefore rarely well-exposed now.

Petroleum exploration has been active in the New Forest area. There was an exploration well in the northwestern New Forest, but it was dry. A seismic study has been made of the Matley area, and no doubt, a very large amount of seismic data on the area exists.

For a bibliography and for references on the geology of the New Forest please go to the separate New Forest Geology Bibliography . More relevant literature is given in a related bibliography on the Solent Estuarine System, (and see Solent Bibliography - Topics ).

Good geological exposures and interesting geomorphological features are present in the coastal areas at the southern fringe of the New Forest National Park. See the following:

Beaulieu River Estuary
Calshot Spit and Stanswood Bay
Lepe Beach and Stone Point
Solent-Introduction
Barton-on-Sea
Hordle Cliff and Milford-on-Sea
Lymington-Keyhaven Coast
Hurst Spit
Petroleum Exploration, South of England
Lepe Beach and Stone Point.

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INTRODUCTION:

Safety on Field Trips to New Forest

The New Forest attracts walker and horse riders, but not geologists on any appreciable scale because of relative lack of exposures. Geomorphologists and environmental scientists are more likely to visit and would also be interested in the geology. The New Forest is not particularly hazardous but geologists and other scientists and naturalists must be aware of those few risks that do exist.

There is much boggy ground in the New Forest but if you keep to tracks and footpaths there is little hazard from this. Any exploration off tracks or paths should be undertaken cautiously. Geological work may involve study of stream beds and springs because there are few exposures of Eocene sediments elsewhere. Here, soft clays are likely to be encountered and it is possible to become stuck in these. Carry a map and compass or GPS becuase it is very easy to get lost in the woods if there no knowledge of the direction of travel, especially at dusk. A torch and a mobile phone are necessary.

Avoid interfering with forest ponies or cattle. Adders are present on the heaths but are rarely seen. They are not aggressive but should not be touched. In storms there can be risk from falling tree branches. Any study of road cuttings needs care with regard to passing traffic. You are reminded that there is a 40 mph speed limit on the unfenced roads, because of wandering ponies and cattle, and that valuables should not be left in cars in the New Forest car parks because of possible theft. You should not disturb conservation areas, plants or wildlife in general. Abide by the rules and byelaws of the New Forest National Park. Any geological or geomorphological or other field work, walking or exploration is done at your own risk and no liability is accepted here.

The comments here refer to the inland New Forest area, ie. heaths and woodlands etc. Safety with regard to activities on the coast are considered in individual webpages on those localities, and reference should be made to those pages.

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INTRODUCTION:

Maps, Topographical

Location map for the New Forest

An old, topographic map of parts of the New Forest and the Solent Estuaries, southern England, probably from about the 1920s

Part of a map by Percival Lewis showing the Beaulieu River Estuary or Exe Estuary, Hampshire, in 1811

Part of a 1810 Ordnance Survey map showing the Beaulieu River Estuary, Hampshire

A classified, false-colour, satellite image of the southern part (Beaulieu area) of the New Forest National Park, Hampshire, with only some partial interpretation

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INTRODUCTION:

Geological Maps

Simplified geological map of the Hampshire Basin around the  Solent Estuaries, southern England

Simplified geological map of the New Forest

Purchasing Geological Maps from BGS

Most of the annotated, small parts of geological maps of the New Forest shown below are old versions, some very old. It is strongly recommended that the reader obtain the new versions of the 1:50,000 geological maps from the:

British Geological Survey Bookshop - Online.

These are not expensive, and usually about 12 each. They can be obtained folded or flat.

Index and history of the British Geological Survey, geological maps of the New Forest, Southampton, and adjacent regions

British Geological Survey Memoir and Map 315 for the Southampton Area

Geological map of the central part of the New Forest, including Lyndhurst, Ashurst and Beaulieu Road Station, modified and annotated after part of Sheet 315, Southampton

Old Geological Maps

The old geological maps, many dating from the 1890s, are very useful and provide valuable information if used with a little geological skill and experience. The stratigraphical units are less subdivided on these old maps and in some areas they do not provide the correct indication of the underlying strata. Sometimes, though, they are very good.

The terminology may be different and it is important to recognise the real stratigraphical limits of the mapped units. For example the Bracklesham Beds of the old maps normally includes the Earnley, Marsh Farm and Selsey Formations of the Bracklesham Group, but not the Wittering Formation, which is usually classified as "Bagshot Beds". Thus do not expect old and new maps to tie in in an exact manner at their junctions where Bracklesham strata crop out. Note also that that Selsey/Barton boundary (i.e. Bracklesham/Barton boundary) is not always taken at the same horizon. It is now mapped on mainly lithostratigraphic terms and is, more or less, a sand/clay boundary. On older maps the attempt would have been to mark the start of the Barton Clay by the Nummulites prestwichianus Bed (although this can be difficult to find). The London Clay limits may also vary to some extent. As mentioned elsewhere, there can also be problems with the Chama Bed on the new maps, and in some areas the old Barton Clay/Barton Sand boundary system is easier to understand.

Most of these problems can be overcome by studying the respective maps and memoirs of different dates, and by incorporating field observations and borehole data. It is essential firstly to fix a stratigraphical classification for use, and that for the Southampton Sheet, 315, and the memoir of Edwards and Freshney (1987) is recommended. However, understanding the old scheme and its relation to this is also necessary.

Geological map of the northeastern part of the New Forest, part of Sheet 315, Southampton, old edition, annotated

Geological map of the northwestern part of the New Forest, part of Sheet 314, Ringwood, old edition, annotated

Old geological map of the eastern part of the New Forest, including Hythe, Dibden and Beaulieu Road Station, annotated, and after part of the 1899 edition of Sheet 315, Southampton

Late Victorian geological map of the Lepe area, Hampshire

The geology of the Beaulieu River estuary, Hampshire, as surveyed in 1893, and with some updating

Detailed geology of the Lymington area, Hampshire, as shown on an old geological map

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INTRODUCTION:

Brief Overview

The New Forest National Park occupies an area of Eocene sands and clays covered in many areas by about 3m thick spreads of Pleistocene flint river gravel. The Eocene sediments are relatively soft deposits (actually "firm" in civil engineering terms) with every variation between pure sand and pure clay, much of it a mixture of both. These beds are fossiliferous underground but near the surface are weathered and have lost their fossils. The Bracklesham Group and Barton Group are of marine origin and contain bivalves, gastropods and occasionally sharks' teeth. There are some limited fossiliferous exposures in New Forest stream beds, such as at Studley Wood, discussed below. A notable area for these is Brook and Bramshaw. They contain much of the green clay-mineral glauconite, but this weathers near the surface to brown iron-rich sediments. Pyrite and particularly siderite are constituents which in place oxidise to limonite and to brown colloidal compounds of organic matter and iron. This results in chalybeate springs or iron springs. These are widespread in the areas of the Bracklesham and Barton outcrops, and the most notable example is the Irons Well near Fritham. Some New Forest springs, particularly those associated with the Chama Sand of the Barton Group, can form small treacherous bogs. The clays of these stratigraphical units produce boggy ground. Sands, particularly the Becton Sands (Barton Sands) tend to form hills with steep slopes. Examples can be seen in the Burley area. If the sand is not seen directly, its presence may be made visible by badger burrows. The dips are almost always very low, so that in any one limited area the stratigraphy appears to be "layer cake".

The southeastern part of the New Forest is rather different because it contains uppermost Eocene strata of the Solent Group. Much of this is lacustrine or lagoonal with numerous bivalves and gastropods of low-salinity to brackish type. The carbonate content of these beds is relatively high and they are often regarded as marls. These more calcareous strata have been dug in places for marl pits. The part of the Solent Group under the southeastern New Forest is the Headon Hill Formation. Within this is a notable coral bed which was at one time exposed in the railway cutting between Brockenhurst and Sway. These more calcareous strata are particularly good for farmland and the valuable estates of the Beaulieu area mostly lie on Headon strata.

The Oligocene strata are present on the nearby Isle of Wight, but in the New Forest there is probably no Oligocene, and certainly no Miocene or Pliocene. Lying unconformably on the Eocene are the Pleistocene fluvial gravels. These spreads are on river terraces with the older ones being at greater height and are particularly present in the northern New Forest. The subangular flint gravels have been washed down from the Chalk outcrops of Salisbury Plain and elsewhere in the periglacial conditions which existed here until about 10,000 years ago. It is likely that the floods from the melting of the snows in spring transported this relatively coarse debris. There was no actual glaciation just here but it occurred further north in Britain. The New Forest area was tundra with seasonal floods of braided rivers, and cold and icy much of the time. Now, in the mild climate of the present interglacial, it is now prevented by human activity and by grazing from becoming a completely wooded forest. The heaths are fire-savanas, resulting from controlled burning. Because of this much of the New Forest still looks rather like the barren tundra that it has been until recently. It differs, however, from its original natural condition particularly by the absence of elephants and other large mammals (remains occur at Lepe Beach, in the Avon Valley, and across the water in the elephant bed of Selsey Bill). They would probably still be here, were it not for human activity. Of course, the higher temperature now would be too great for mammoths but in natural circumstances, as in previous interglacials, there would be other elephants present that could tolerate the present warm conditions.

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INTRODUCTION:

New Forest Soils and Soil Maps

Location and limits of  the Soil Survey of Hodgson and Whitfield (1990), which includes a northeastern part of the New Forest National Park

A map of the major soil groups, redrawn after Hodgson and Whitfield (1990), and including a northeastern part of the New Forest National Park

The soils of an area (150 square km.) including the extreme northeastern part of the New Forest have been investigated, using a computerised system, by Hodgson and Whitfield (1990) of the Soil Survey and Land Research Centre, Cranfield Institute of Technology. The results have been reported in their publication: Applied Soil Mapping in the Southampton Area. It is the result of detailed soil survey carried out at 1:10,000 scale. There are 12 maps, the subjects of which provide a good indication of the contents of the report. The maps are as follows:

1. Generalised Soil Map - Major Soil Groups.
2. Disturbed land.
3. Shrink-swell potential.
4. Soil vulnerability to damage whilst handling.
5. Hydrology of soil types (HOST).
6. Erosion risk.
7. Suitability for individual crops - maincrop potatoes.
8. Land capability for forestry.
9. Wetland habitat potential.
10. Suitability for recreational use - golf course construction.
11. The distribution of samples (trace overlays). (in pocket at the back)
12. Basic soil map at 1:25,000. (in pocket at the back).

Some brief notes on New Forest soil types have been added below and are partly based on Hodgson and Whitfield (1990).

Surface-water Gley Soils
This common type of gley is the most extensive soil type within the New Forest part of the map, shown above. Gley soils occur on weathered clays (often blue-grey and pyritic at depth where unweathered) with partial oxidation. Gleys usually show mottled oxidation patches and streaks in darker, bluish grey clay matrix. The brown areas are where the pyrite in the clay has been oxidised to goethite. More extreme weathering can turn these clays into a yellowish mud at the surface, a common feature of New Forest ditches. The surface water gleys are wet soils generally above the water-table but wet and soggy from surface and run-off water.

Surface-water gleys are widespread above the Barton Clay. They also, however, show a strong correlation with the Chama Sand Member. This is because the Chama Sand Member is mainly clay in some places, particularly in the eastern New Forest (it has been excavated in the Fawley Power Station outfall). Even when mainly sand it is usually an argillaceous sand. A further problem is that that there can be vertical transition from clay to sand within the Member. The problem is brought out by the fact that on the old Geological Survey maps the Chama Sand was often mapped as Barton Clay.

Surface-water gleys can also occur on areas of the London Clay and on the argillaceous members of the Bracklesham Group.

Ground-water Gleys
These are common on river alluvium of flood plains. They can also include alluvial soils and soils affected by fluctuating groundwater on low terraces flanking the flood-plain alluvium. Because they are low and near rivers they can be separated from surface-water gleys.

Peat (organic) Soils
Peat can accumulate under wet conditions on low-lying ground, often close to a stream and it may be within a floodplain. There has been a difference of opinion on different geological maps as to just what is peat and just what is organic-rich alluvium. Thus, use the geological maps with care.

Podzolic soils (podzols or podsols)
Podzols usually occur on high gravel terraces with good drainage. These are the Pleistocene "Plateau Gravels" of the New Forest. They can in some cases develop on arenaceous and well-drained parts of the Bracklesham Group. They are easily recognised by white, bleached flint pebbles at the surface, and in many cases an iron pan (with manganese) a metre or so down.

Brown soils
Brown soils can occur on loamy and sandy deposits of the Bracklesham and Barton Groups. They can also occur on low level Pleistocene gravel terraces ("Valley Gravel"). Recognition of them is helped by the fact that they are obviously not podzols, gleys or peats.

Disturbed land
This category includes quarries, "brown-field land", landfill etc. It is widespread in urban areas, but is limited in extent in the New Forest. Much gravel has been excavated but there has only been landfill in a few places.

Calcareous soils of the southern New Forest
Not discussed here are the calcareous soils or marls that occur on parts of the Headon Hill Formation. These are not present within the area of the map shown above but are widespread south of Lyndhurst and in the region of Brockenhurst, Lymington, and Beaulieu.

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STRATIGRAPHY:

Barton Clay in the New Forest

Sandy Barton Clay in a road cut at Hounsdown, northeast of the New Forest, Hampshire

Septarian nodules from the base of Bed C of the Barton Clay are being eroded out at the foot of the cliffs at Naish Farm, near Highcliffe, 2006

Barton Clay, very sheared, and exposed beneath Pleistocene gravel, in excavations for the foundations of Fawley Power Station, Southampton Water in about 1964

The Barton Clay, of Eocene age, is an important stratal unit in the New Forest area. The cliff section at Barton-on-Sea provides the key reference succession for the New Forest. The Barton Clay has been exposed in minor excavations here and there in the forest, and on a larger scale in the foundation diggings for Fawley Power Station. It is very fossiliferous at the coast, and also at some inland locations, such as Burley. Elsewhere, as at Fawley, it is poorly fossiliferous (although containing nummulites).

The Barton Clay forms extensive areas of boggy ground in the New Forest, and some of these can be difficult to cross in winter. The Becton Sand (Barton Sand) forms good dry walking or riding heathland. Particularly treacherous boggy springs break out, though, in places at the junction of the Becton Sand (main part of the Barton Sands) and the Chama Sand (argillaceous sand just above the Barton Clay), as on the hillside south of Yew Tree Heath near Beaulieu Road Station (map reference SU 366065).

In the 19th Century, during the construction of the railway between Christchurch and Brockenhurst a good section in the Barton Clay and Sands was opened in the cutting of Hinton Admiral Station, a little more than 1.6 km north of the coast (White, 1917). Shell beds at the top of the Barton Clay were found to be thicker than at the coast, but the Chama Bed was unfossiliferous (Gardner, Keeping and Monckton, 1888). If, as those authors considered, the greenish clay in the western part of the cutting belongs to the Lower Barton, the thickness of the Middle Barton is reduced to a little over 9m, compared to 16m on the coast.

Further north, dark greenish and grey sandy clays with ironstone nodules, in the lower part of the Barton Clay, were once exposed in brickyards at Bransgore and Crow (White, 1917). Bluish sandy clay was once worked in a brickyard 0.8 km north of the village.

The Barton Sands have been dug in many places, but the sections are not of particular interest. This is because the sands, unless buried under younger clays are weathered to white or yellow and have lost their fossils. Shells have been dissolved away, leaving only indistinct impressions in iron oxides.

On the Bournemouth, western, side of the New Forest, there have been some exposures of Barton Sand. Near the New Forest boundary but not within the forest were the following: On the western side of Poors Common near Bransgore; beneath the Plateau Gravel on either side of the road from that village to Thorney Hill; and north-east of Charles Farm near Crow. Within the limits of the forest there was an exposure in the old railway cuttings of the former Brockenhurst-Ringwood railway line through Cranes Moor (White, 1917)..

Bolton's Bench Lyndhurst is Barton Sand. So too is The Ridge and the Park Pale, the ancient limits of a deer park. The higher ground around Beaulieu Road Station is on Plateau Gravel and Becton Sand (Barton Sand) and gives good riding.

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STRATIGRAPHY:

Barton Clay at Burley

Turritella in Barton Clay from Burley New Inclosure, New Forest, Hampshire

Fragment of Athleta in Barton Clay from Burley New Inclosure, New Forest, Hampshire

The Barton Clay occupies much of the Burley area, as does Barton Sand. It is not often exposed in good unweathered condition. At depth it is blue grey with some white aragonitic shell fossils but at the surface becomes a yellow sticky clay with no fossil shells remaining.

When riding in Burley New Inclosure on Sunday 24 July, 2005, I noticed a heap of fossiliferous blue-grey clay. This looked like typical Middle Barton Clay from the Barton coast section (from superficial appearance it reminded me of bed E). I have not made any detailed study of the mollusc content but it seems to contains the following. This is only a rough list for guidance and it is hoped that a more accurate and more extensive list will become available later.
Turritella imbricateria (common)
Athleta (one broken specimen seen, probably Athleta luctator)
Cardita sulcata
Crassatella sulcata (small)
Natica
Ostrea
(a small smooth form)
Sycostoma pyrus
and various small Pleurotoma - type gastropods

Scaphopod - "Dentalium" - Anatalis striata? (small form)

In other words this is, at first sight, a fairly standard Barton Clay assemblage. The shells are as abundant as in the Barton coast section, but are mostly small specimens (although larger ones may have been broken up in the excavation procedure). A Barton Clay specialist would be certain to find more and to identify the difficult small species and then could probably relate this bed to a numbered bed in the Barton coast section. There are some accumulations of small shells of the "shell bed" or "stone bed" type, although the material is not lithified. If more information becomes available it will be added here.

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STRATIGRAPHY:

Brockenhurst Bed

(Initial notes for additions)

Coral-bearing marls occur in the New Forest in the Headon Hill Formation ( the Middle Headon Beds in old nomenclature). These were once well-exposed in the railway cuttings between Brockenhurst and Sway, and a famous feature of New Forest geology. Martini (1970) has demonstrated on the basis of fossil microplankton (coccoliths) that the Brockenhurst Bed does not correlate with the type Lattorfian (the Lower Oligocene, Latdorf Beds of Germany), as was once supposed (Koenen, 1864), but is somewhat older.

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STRATIGRAPHY:

Pleistocene Gravel Terraces

The New Forest is characterised by Pleistocene gravel terraces descending from higher levels in the northern New Forest to lower levels near Southampton Water, the River Avon and the coast. [details will be added]

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TOPIC:

Burley Rock - Introduction

There are two main categories of hard ferruginous rock cropping out in the New Forest. One is "heathstone" as at Hasley Hill, and this is discussed further below. The other is "Burley Rock". This, which can examined in detail in a wall in Burley Village, is discussed first.

A wall of Burley Rock at the corner of Garden Road, Burley, New Forest National Park

A wall of Burley Rock, Burley Village, New Forest National Park

A close-up view of Burley Rock in a wall at Burley Village, New Forest National Park

A very close view of Burley Rock, in a wall at Burley Village, New Forest National Park

Burley Rock of sandstone type, wall at Burley Village, New Forest National Park

In the New Forest most of the sediments are either Tertiary sands and clays or Pleistocene gravel. Thus the occurrence of a hard rock, the Burley Rock, at Burley is unusual. It consists irregular blocks of brown, limonite or goethite-cemented Pleistocene sandy gravel or sandstone.

No proper study of the rock or its pebbles has yet been made. From superficial examination it is obvious that the flint pebbles within it are very poorly sorted. The details of them are less known. The pebbles seem to be predominantly subangular, but vary from subrounded to angular. Some rounded pebbles of Tertiary type seem to be present, but they are not dominant. The pebbles appear to have been whitened internally and then stained brownish by iron hydroxides at the surface. Some of them show small pits. This type of gravel is common in the Pleistocene river terrace gravels. There it is fluvial in origin and probably transported fairly rapidly at times of melting snow. The region in the Pleistocene was periglacial and not glacial. Exotic pebbles are not normally present and the material is debris from the Chalk with Flint uplands of the Salisbury Plain area. It is normal for the Pleistocene gravels to contain scattered rounded flints derived from local Tertiary pebble beds.

There is very little hard rock in the New Forest area so that in the past, before modern transport, the Burley Rock was important as a source of rock for walls and foundations of churches etc. It superficially resembles the "heathstone" of Studland, Dorset (see the Church), although that is cemented Tertiary sandstone. There are the remains of old quarries for the Burley Rock in the Burley area, but there is very little to be seen as natural exposures now. However, the rock can be seen quite easily in walls at Burley and Lyndhurst and probably elsewhere. Photographs above show a good wall of this rock at the junction of Garden Road and the main road to Bransgore from Burley. Elsewhere in the New Forest, as at Woodlands, isolated pieces of similar rock may be encountered. These may not necessarily, though, have come from Burley.

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Burley Rock

Use of the Stone for Building

There has probably been much use in New Forest buildings in the past, although it may be covered by plaster or whitewash. According to Hampshire Treasures, Volume 5, there is a report of use of Burley Rock at Mill Lane, Burley.
"The Grist House, Mill Cottage, Mill Lane. Timber- framed. Built of brick and Burley rock. Mill as such ceased to work circa. 1820. Ref: Records of Burley, p. 152."

Also:
"Little Pound Farm. Thatched roof. Whitewashed walls built of Burley rock, cob and bricks. Ref: Records of Burley, p. 157."

Burley Rock is also reported to have been used in the walls of Queen,s House, Lyndhurst. See: New Forest Notes September 2005.

See also:

Burley and Fritham with Eyeworth: Conservation Area Character Appeal. New Forest National Park. The following paragraphs are from this substantial pdf report.

"Of a similar size and status is Beacon Cottage, part of which dates back to the middle of the 18th century and was constructed of Burley Rock. It was much extended in the late 19th and early 20th century."

"5.2.4. A material known locally as Burley rock, a locally occurring iron stone, was often used for the footings of cob buildings and also as a walling material with brick dressings to window and door openings, or quoins and in the case of Little Pound Farm, the ground floor is built of Burley rock and the first floor of brick. The late 19th and early 20th century fashion of stucco or rendering the exterior of cottages may well be disguising many other buildings constructed of cob or Burley rock."

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TOPIC:

Burley Rock - Problem of Origin

The location of Burley Rock named sites as shown on the Ordnance Survey map, Burley, New Forest National Park

Part of the geological map, Sheet 329, showing the relationship of the Burley rock to the geology of the Burley area

There are the following three points of evidence regarding the Burley Rock:

1. It contains leached, subangular flint pebbles. Thus it is not a Tertiary deposit, but must be of Quaternary origin. The subangular flints are typical of Pleistocene gravels and unlike the beach-battered, rounded pebbles of Tertiary pebble beds. The leaching is a podzol soil process and not usually seen in Tertiary pebble beds.

2. There is a large proportion of sandstone. However, this often contains scattered flints of Pleistocene type and therefore does not seem to be Tertiary sand in place. However, there is too much sandstone for typical Pleistocene gravel deposits. Hillwash from sand and gravel sediments best explains the lithology.

3. It occurs at a scarp of gently south-dipping Chama Member and Becton Sand, over Barton Clay in the valley of the Mill Lawn Brook. See the geological map above. The localities are marked on the topographical map as Burley Rocks and Rock Hills. These places seem to be on the middle to upper slopes, probably about 50 metres above sea-level, and not on the valley floor.

4. Head Gravel is present in some of the area where the Burley Rocks have been found. There may be some association with this gravelly head or colluvium. Pleistocene terraces 13 to 14 on the plateau to the south provide the gravel.

Thus there a few relevant points but the specific origin of the Burley Rock is not known in detail. It is possible that it is of iron-pan origin at the base of a podzol profile. However, it is relatively thick-bedded and iron-pans are usually thin. If it is of podzol, horizon B (illuvial) then the cementation has to involve both gravel and a greater proportion of sand.

An origin from iron springs is quite likely. There are existing iron springs at Red Rise in the Mill Lawn Brook east of Burley. These are about only a kilometre to the northeast of the main Burley Rock area. The origin of chalybeate springs in this region is easily explained. The brook is on Barton Clay. However, about 200 metres south of the brook is the outcrop of the Barton Sands (Chama Bed and Becton Sands). Much of the Barton Sands, is pyritic and ferruginous, so this is a reasonable source of iron.

Chalybeate or iron spring at Red Rise, near Burley, New Forest, in 2003

It is of interest that at Red Rise, about 2 and a half kilometres to the east of Burley and quite near Burley Rocks location, there is a iron spring or chalybeate spring into the stream. This is shown in a photograph here. Because of the proximity of this directly east of the site of the Burley Rocks, it seems unlikely to be a coincidence. Iron springs, once present on a larger scale seem, at present, the most likely explanation of the origin of the cementation of the Burley Rock.

Iron springs flowing out over the Becton Bunny Bed (clay), Barton Sands, at Beacon Cliff, near Milford-on-Sea, Hampshire

Iron springs, or chalybeate springs also emerge from the Barton Sands (Becton Sands), the same beds present in the area east of Burley, at Hordle Cliff on the coast.

Iron-cemented beachrock associated with ferruginous waters from oxidising iron pyrites and the formation of jarosite, south coast of Brownsea Island, Poole Harbour, Dorset,UK

Ferruginous springs from pyritic Eocene strata cement the beach sand and gravel on Brownsea Island in Poole Harbour. These springs emerge from an older part of the Eocene, but show that this process can take place in the region.

Thus it seems very probable that the Burley has by iron springs from the Barton Sands cementing sand and gravel hill wash containing flint pebbles. The details at Burley are not yet fully understood, though. Further study is needed.

(Additional note. Barton Sand is also present at Iron's Hill, another locality with something of a mystery regarding iron. See the Iron's Hill section in this webpage.)

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TOPIC - HEATHSTONE:

Hasley Hill - Heathstone

A podzol soil profile has produced iron-cemented sandstone or

Following discussion of Burley Rock, a different iron-cemented sandstone at Hasley Hill, known as "Heathstone", needs to be considered. More information on Hasley Hill is given below. See the section:

LOCATIONS - Hasley Hill.

Iron-cemented sandstone can sometimes be found on the heaths of Hampshire and Dorset and has been know as heathstone. It is very common in the Studland area and has been used for building Studland Church. That particular iron-cemented sandstone is Eocene sandstone which has been cemented under some burial. It resembles the sandstone of the Agglestone, and is often very coarse and cross-bedded. It is not usually composed of Quaternary sediments (easily recognised by the presence of bleached, subangular flint pebbles).

The Burley Rock, iron-cemented Quaternary sand and gravel in the Burley area is a special type of iron-cemented sandstone and conglomerate and is discussed separately above.

The possibility must be considered of a hard, iron-cemented sandstone occurring deep underground in the Tertiary strata. However, in the Eocene sediments beneath the New Forest hard, iron-cemented sandstones have not been commonly reported, and they are not normally found in the cliffs of these strata in Christchurch Bay (except for siderite nodules). There are many Eocene sand beds beneath the New Forest, particularly in the Bracklesham and Barton strata, but they are either argillaceous, uncemented or locally cemented by carbonate (which does not usually survive the acid soil conditions of the New Forest). Thus it seems unlikely, but certainly not impossible, that any ferruginous sandstone outcrop is that of an old cemented sandstone within the Tertiary strata.

With regard to Hasley Hill, iron-cementation of sand beds within the soil profile seems more likely. In the New Forest podzols have often been formed by acid soil-forming processes. Usually these are seen as gravel sections with white bleached (A - eluvial zone) pebbles at the top and iron-cemented gravel or iron-pan (B - illuvial zone) lower down. Podzols could be developed in Tertiary sand deposits where they crop out. At Hasley Hill there is Bracklesham sand. In the upper part of the hill the sands are almost white in colour and seem leached. This upper part of the hill slope may be revealing the upper part of the soil profile (the A2 horizon). The iron-cemented sandstone occurs lower, and thus could be in the B2 horizon.

The podzol origin cannot be claimed as proven because a good vertical section showing both in appropriate sequence has not been seen. However, supporting the podzol theory there is the occurrence of red, iron precipitation in weathered Tertiary clays on the lower slopes. This seems to be in the lower part of a podsol profile in which the iron-cemented sandstone is an iron-pan. Obviously, further study of New Forest ferruginous soil profiles is needed.

The heathstone is of interest because there are few hard rocks in the New Forest, other than the Burley Rock. It probably was, therefore, of importance for local construction in ancient or historic times. The heathstone of Hasley Hill has been discussed by Sumner (1931, A Winter Walk in the New Forest, p. 192):

"On, beyond, on the Northern side of Hasley lnclosure, there is another sandy knoll of which the sand is bright orange in colour, containing fragments of ironstone limonite, a concretionary natural product of sand indurated with iron, which sometimes forms around roots in the subsoil, and when in time such roots have decayed and wasted away, ironstone tubes remain to provoke question.

Near here, outside the Eastern end of Hasley Inclosure, there are extensive remains of rambling pits and hollows with up-turned mounds adjoining that may have been made for obtaining ironstone, or heathstone as it is locally called; a stone that was evidently valued by the Romans, for it is constantly found on Roman sites throughout this part of Britain. They used it for the cheeks of hypocaust and kiln furnaces, and for the lining of flues exposed to great heat, because it does not splinter under such conditions; it burns from orange-brown to wine-red under the action of continuous fire. Similar, though lesser, pit diggings may be found on other hilltops near here; notably on the summit of a sugar-loaf hill that rises above Purlieu Pound bog in Ogden's Purlieu, and at "Pits" on Ibsley Common, where we know that these diggings date back, at least, to Medieval times by the name given to this place in New Forest Perambulations of Edward I, "Putts in Merkynggeslade", and of Charles II, "The Pits," and infer that heathstone was the material sought for, by present-day experience that this stone may still be found here."

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LOCATIONS


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LOCATIONS:

Marchwood, Dibden, Applemore - General

The Horse-Swimming Lake at Applemore, Marchwood, New Forest, Hampshire, was excavated in the Chama Bed, which hold water at this locality because of high clay content

An old, 1893, revision of the topographic 1 inch map of Hythe, Dibden and Marchwood, eastern border of the New Forest National Park, with part of Southampton Water shown, Hampshire

Old geological map of the eastern part of the New Forest, including Hythe, Dibden and Beaulieu Road Station, annotated, and after part of the 1899 edition of Sheet 315, Southampton

The Becton Sand of the Barton Group (Eocene), exposed in a ditch at Applemore, near Marchwooe, New Forest National Park

Details of the Barton Group at Langley Lodge, near Marchwood, New Forest, Hampshire, modified after Edwards and Freshney (1987)

Parts of both topographic and geological 1 inch maps of the Hythe, Marchwood and Dibden area are shown above. This is initial background information for local detail of the geology which is to be added later. See particularly the important memoir by Edwards and Freshney (1987), which provides much detail about the Barton Group (Barton Clay, Chama Member, Becton Member) in this Waterside Area and eastern New Forest area.

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LOCATION:

Fawley Oil Refinery

An old aerial photograph of the southwestern side of Southampton Water, with Fawley Oil Refinery, probably from about the 1970s</A>

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LOCATIONS:

Hunter's Hill, Colbury, Part of Langley Manor

Well affected by Portsmouth Earthquake of May 31st 1889.

The details of a borehole at Colbury are given below. Most of the information is from Whitaker (1910) but I have added a few additional notes and interpretation. The borehole mostly in Barton Clay, although in places of very sandy facies, with Selsey Sand, Bracklesham Group, at the base of the well.

"Well bored and communcated by Messrs. Isler. Notes from specimens and Mr. T. Lloyd of Winchester. Details from Whitaker (1910).

Water level about 80 feet down. After pumping for 9 hours could not be lowered below 100, quickly returning to the natural level. Yield 300 gallons an hour.

[figures are in feet, depths are bed bases]

Well Record

Old dug well(cylinders since carried down to 96 feet by Mr. James Grace. To depth 28ft.

Clay [probably Barton Clay] - thickness 7ft, depth 35ft.

Blue sandy marl (specimen of grey clay with greenish [glauconitic] sand) - thickness 39ft, depth 74ft.

Stiff blue clay [Barton Clay], thickness 8ft., depth 82ft.

Sandy blue clay [Barton Clay], thickness 4ft., depth 86ft.

Stiff clay [Barton Clay], thickness 12ft., depth 98ft.

Sandy marl (specimens of green-grey [glauconitic] clayey sand or sandy clay), thickness 27ft., depth 125ft.

Stone (specimen of hard calcareous clay)[probably a septarian nodule of argillaceous limestone, but possibly, an argillaceous limestone bed], thickness 1 foot, depth 126ft.

Sand (specimens of green-grey [glauconitic?] clayey sand or sandy clay, with bits of shell at 136 and 148ft.; then specimen of greenish grey clay, thickness 31ft., depth 157ft.

Sandy clay, thickness 1 foot, depth 158ft.

Sand, thickness 7 ft., depth 165ft.

Stiff sandy clay (specimen of find greenish-grey clayey sand at 178ft.; of greenish sandy clay at 200ft.; of brown grey clay at 204; of dull brownish clay with a little greenish sand, at 205ft.) thickness 40ft., depth 205ft.

Stiff clay, thickness 6 ft, depth 211ft.

Stiff sandy clay (specimens of brown-grey clay, with shells, at 213ft. and 218ft.; of greenish-grey sand with shells at 223ft., and of brown clay, with shells, at 226 and 231, the latter tough), thickness 23ft., depth 234ft.

Stiff green sand [probably Selsey Sand, Bracklesham Group, but not proven] (specimens of brownish and greenish sandy clay, clayey sand and sand, often with shells down to 300ft [91.4 metres]. A four inch bed of sandstone at 285 ft. [a 3 inch bed of sandstone was encountered at Fawley Power Station in the upper part of the Selsey Sand Formation] [87metres]). Thickness 76 ft., depth 310ft." [94.5m. TD]

[End of well record]

.

Note: By comparison with the Ramnor Inclosure Borehole (near Brockenhurst), Fawley boreholes etc Edwards and Freshney (1987) and by reference to the geological map, sheet 315, it would be reasonable to expect the base of the Barton at round about 60m depth (about 200feet). The lowest unit of "stiff green sand" is almost certain part of the Selsey Sand (Bracklesham Group).

Comment received by Mr. William Whitaker:
"Mr. T. Lloyd told me that after the slight earthquake-shock felt here on May 31st, 1889, large quantities of sand came up with the water, so as to cut out the leathers, which had to be replaced, and then to stop the supply. Before this the water had been free from clay for months."

Stephen Pomeroy records in a pdf file - Weather [and earthquake records regarding the Portsmouth area] that "Earthquake tremors [were] felt in Portsmouth" in May 1889. Although Chichester is most well-known place for earthquakes in the Hampshire-Sussex region, Portsmouth seems to have had a fairly regular history of minor earthquakes, occasionally causing damage. I assume that this event of May 1889 was the same earthquake that affected the well at Hunter's Hill, Colbury. This New Forest location is quite close to an east-west basement fault, downthrowing north, according to Melville and Freshney (1982), Fig. 31 (although I have not checked recent data from seismic). This fault is not visible at the surface (it would presumably be sub-Albian).

The sand problem in the well at Hunter's Hill, Colbury was almost certainly the result of liquifaction of sand. This was probably in the Bracklesham strata, known for problems of "running sand" (or "quicksand"). Such sand has been reported in boreholes in the Earnley Group at Southampton. Earthquakes involve extensional and compressional movements. Seismic shear waves pass through the sediments and this can result in liquifaction (liquefaction) in certain strata. Water-saturated, well-sorted, fine grain sands and silts can temporarily behave as viscous fluids rather than solids. The seismic shear waves distort the granular structure of a sand bed, and cause some of its pore spaces to collapse. The collapse of pore spaces increases the water pressure, and decreases the shear strength. The brief phase of compaction can force ground water and sand upwards where it can escape. (See: McGee - Detection of Bhuj Earthquake Liquifaction). When there is a major earthquake then liquifaction can cause subsidence in certain places and certain circumstances. This has not been reported in the Hampshire region because, fortunately, earthquakes here are usually very small events. The effect in a well at Colbury was trivial. However, it is of interest because it seems unusual in the area and it shows that Eocene sand beds can be affected, at least to some extent, by earthquakes.

Dewatering structures in the Boscombe Sands of Friars Cliff, Highcliffe, Dorset

In the geological past, back in the Eocene, liquifaction and dewatering of Bracklesham sand has taken place on a significant scale. The effects can be seen in the Boscombe Sands at Friars Cliff, Highcliffe and these probably resulted from disturbance of the sands by the violent earthquakes to which this region was subjected during the earliest stages of the Alpine Orogeny (the folding of the Purbeck monocline commenced in the Bartonian).

Incidently, there were reports of water level changes in Wiltshire during the Kent earthquake of 28th April 2007.

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LOCATIONS:

Ironshill, near Ironshill Lodge, between Lyndhurst and Ashurst (MR - SU316099)

Ironshill as shown in Norden's Survey of Medieval Coppices in the New Forest, 1609

Becton Sand or Barton Sand exposed in a blown-over tree, summit of Irons Hill, New Forest, Hampshire, 19th November 2008

Barton Clay exposed in a track-side ditch, northwest of Ironshill, New Forest, Hampshire, 19th November 2008

Ironshill, is a small hill, 41 metres high, and just to the west of Ironshill Lodge (between Lyndhurst and Ashurst). It should not be confused with another Irons Hill at Perrywood Inclosure 2km. east of Brockenhurst. The hill was a Medieval Coppice (Sumner, 1931), and, as shown above, was mapped and described by John Norden in 1609 in a document held at the Record Office, Chancery Lane, London:

"To the consideration of the Righte Honerable the Lorde high Treasurer of Englande and Sir Julius Knighte Chancellor of his Majesties Exchequers.
Forasmuche as his Majesty (at my being convented before the same) seemed to have a princlie desire to have manie New Copices raysed in the New foreste I thoughte fitt to make his Majesty sayde desire knowne to some of the keepers there whome I finde nether willinge to admitt the raysinge of new nor the demisinge or fellinge of the olde under couller of rastrayninge the raunge of the game by the one and abridginge them of covert by the other - which reasons, if they hold forceible, theis certificats are litle avaylable.
Some of the copices also menconed in this booke are by his Majesty express pleasure (as is sayde) absolutelie inhibited to be felled.
The felling therfore of any of the fellable copices may be offensive unto his Majesty and therfore daungerous to the instrument unles his Majesty wilbe pleased to manifest his princelie consent by some warrantable declaration of the same, that the demisinge, takinge, fellinge and dsposing of suche as his Majesty pleasure appeareth to allowe may be freelie and without future question be justified and approved... [continues]
your honors,
J. Norden"

Thus, the hill seems to have been a place where study oaks flourished and mast (acorns) were plentiful for seeding new saplings. It thus become one of the first parts of the

In geological terms, Ironshill is a small eastern outlier of the Becton Sand (Barton Sand in part) which has been quarried in the past at Bolton Bench, Lyndhurst. Chama Sand is mapped on the slopes (unproven boundaries), on the 1987 edition of Sheet 315. Note, however, there are some problems with the Chama Sand Member, since it is transitional to clay both vertically and to some extent laterally. In contrast the 1899 edition of Sheet 315 show Ironshill Lodge and Irons Hill as Barton Clay with Barton Sand further west; in other words the sand outlier was not recognised as such. Because of the fallen trees the Becton Sand on the hill top now, the sand is obvious. The Barton Clay - Chama Sand boundaries in this area are more difficult to prove on vegetated slopes, so some uncertainty should be accepted.

Because of the name and because of some comments in the literature there is an interesting question as to whether ironstone quarrying once took place at Irons Hill or whether there was once a small iron foundry here.

Beddington and Christy (1977) commented that the Irons Hill at Brockenhurst might have been a former foundry or smelting works. They also mentioned that Roman iron furnaces were built on hills, and the ore packed between layers of charcoal, was smelted in tall, cylindrical furnaces placed in an exposed position, so that a draught was caused when the wind happened to blow in the right direction. They were, however, discussing Bramshott, near Liphook, on the western fringe of the Weald iron district, not the New Forest.

Small (1975) was quite specific and stated: (page 74) - "Ironshill, where it is believed ironstone was worked." I do not know the exact location of the old quarry. Remains of a pit should be visible. With regard to strata involved in ironstone quarrying, siderite is present as Bed G, the Stone Band or Shell Band, just below the Chama Bed in the Barton cliff section, although it is not likely that the stratigraphical details will be exactly the same at this distant locality. It should also be noted that the ironstone at Hengistbury Head is generally regarded as in a laterally equivalent facies to the Barton Clay. See the Hengistbury Head webpage for details and discussion.

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LOCATIONS:

Cadnam to Lyndhurst
(including Brockis Hill and Bartley)

Brockis Hill area, near Cadnam, eastern New Forest, Hampshire, shown in aerial view

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LOCATIONS:

Lyndhurst

The Ridge, from Matley to Lyndhurst, New Forest National Park, is formed by an outcrop of Barton Sand (Becton Sand)

Here is the log as given by Whitaker (1910) for a well boring at Lyndhurst. The details were communicated by Messrs. A. Williams & Co. The water level was 6 feet down. The yield was 900 gallons per hour. It provided soft water, with a hardness of 9.5. Sodium chloride was 7.25 parts per 100,000. The amount of free ammonia was found to be high and it was advised to filter the water through sand (see analytical data by Mr. E.C. Berry, October, 1889).

The well seems to have provided a good section from Barton Sand (Becton Sand) down into the Barton Clay. The Chama Member seems recognisable, but the stratal interpretations given here are mine, not the original. The sandstone may have been a septarian nodule, although the possible occurrence of a thin bed of sandstone in the Barton Clay cannot be ruled out.

Stratal Units

.
.
BECTON SAND
(Barton Sand in part)
.
.
---------------
CHAMA MEMBER
---------------
BARTON CLAY FM.
.
.

Sequence

Live yellow sand (i.e. clean sand)
Dead Sand (argillaceous sand)
Live sand (clean sand)
Blue dead sand (argillaceous sand)
Dead sand & shells (shelly argillaceous sand)
Dead sand (argillaceous sand)
-------
Sandy blue clay
-------
Brown clay and shells
Blue clay and shells
Blue clay and sandstone

Thickness

21ft
4ft
4ft
22ft
38ft
7ft
.
5ft
.
4ft
14ft
6ft

Depth

21ft
25ft
29ft
51ft
89ft
96ft
.
101ft
.
105ft
119ft
125ft

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LOCATIONS:

Hasley Hill - Introduction

A map of the Latchmore Brook, Hasley Hill, Sloden, Eyeworth and Ironswell area of the northwestern New Forest National Park, drawn by Heywood Sumner

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LOCATIONS:

Hasley Hill, New Forest - Fordingbridge No.1 Petroleum Exploration Borehole

A two-horse carriage passes by the site of Fordingbridge No. 1 exploratory oil well, Hasley Hill, New Forest National Park

A concrete slab probably capping the Fordingbridge No. 1 exploratory well at Hasley Hill, New Forest National Park

The location of the 1959, Fordingbridge No. 1, Petroleum Exploration Well in relation to some other boreholes of the New Forest and adjacent region

An exploratory borehole for oil, Fordingbridge No.1, was put down by BP (The British Petroleum Company Limiited) at the western end of Hasley Hill (map reference near SU192118), near Ogdens, in 1959. The location is at 229 feet or 69.7 metres above OD. It was a major borehole, especially for that time, extending down to 1368 metres, and penetrating the Mercia Mudstone. There must have been a large drilling rig on Hasley Hill.

Fordingbridge No.1 is the only borehole for petroleum exploration within the New Forest and was drilled at a time when planning and environmental regulations were less strict. However, there was an application for a borehole at Denny Lodge by Shell in 1982. That application was rejected. An important deep borehole for geothermal exploration at Marchwood was drilled at the former Marchwood Power Station. This also provided useful information to the oil industry.

There follows an extract from Falcon and Kent (1960), pp. 48-49, giving summary information on the well at Hasley Hill. Norman Leslie Falcon was the Chief Geologist of BP. and Dr. Percy Edward Kent (well-known as Peter Kent, F.R.S.), Geological Advisor of BP Exploration (Canada).

"MORE RECENT BORINGS IN SOUTHERN ENGLAND
...

(c) Fordingbridge, Hampshire
Lat. 500 54' 17.7"; long. 010 43' 59.6"; elevation 229 feet O.D. [69.8m.] [Mr A.P. Terris was Resident Geologist at the borehole]
The section of Fordingbridge No 1, drilled on a gravity and seismic high at Ogdens (Hasley Hill), near Fordingbridge, is still being worked out, but the following brief account may be given.

Drilling began in the Tertiary beds of the Hampshire basin; the Chalk was reached at 678 feet and. the Upper Greensand and Gault penetrated from 1997 to 2251 feet. Beneath the Gault the well passed directly into Kimmeridge Clay, shown by a core 20 feet below the top to be Lower Kimmeridge (with Aulacostephanus, etc.). Only 210 feet of Kimmeridge Clay remained beneath the Gault. The unconformity eliminates the Lower Greensand, Wealden, Purbeck, Portland and Upper Kimmeridge, measuring approximately 4000 feet in eastern Dorset (the nearest outcrops) and some 2700 feet at Portsdown on the other side of the same Tertiary basin. This represents a very considerable pre-Albian uplift.

Beneath the Kimmeridge the boring proved a normal sequence of Corallian (about 170 feet), Oxford Clay (about 430 feet), Cornbrash (35 feet) and Great Oolite Series (404 feet). The last-named was mainly limestone, with only a minor development of argillaceous beds which could be ascribed to the Fuller's Earth, in marked contrast to recent borings nearer the Dorset coast (see the account of the Radipole borings). Below, 118 feet of sandy and ferruginous limestones and ironstones are ascribed to the Inferior Oolite, and beneath this the well proved an Upper Lias development of Bridport Sands type, 250 feet thick. The remainder of the Lias was normal, except that the Middle and Lower subdivisions totalled only about 450 feet and rested upon 60 feet of beds ascribed on fossil evidence to the Rhaetic. The well was completed at 4487 feet, 106 feet into the Keuper [Mercia Mudstone]."

Borehole Succession in Listed Format:

Rotary Table (?) - 229ft. - 69.8m. ht. above O.D.
Tertiary - middle of Bracklesham Group downwards
(678ft - 206.7m. thickness)
Base of Tertiary and top of Chalk - 678ft. - 206.7m. depth.
Chalk (1319ft. - 402m. thickness)
Base of Chalk and top of UGS - 1997ft. - 608.6m. depth.
Upper Greensand & Gault
Unconformity - 2251ft. - 686m. depth.
Lower Kimmeridge Clay (210ft. - 64m. thickness)
Base of KC and top of Corallian - 2461ft. - 750m depth. depth.
Corallian (about 170ft. - 51.8m. thickness)
Base of Corallian and top of Oxford Clay - 2631ft. - 801.9m. depth.
Oxford Clay - (about 430ft. - 131m. thickness)
Base of Oxford Clay and top of Cornbrash - 3061ft. - -932.9m. depth.
Cornbrash - (35ft. - 10.7m. thickness)
Base of Cornbrash and top of Great Oolite - 3096ft. - 943.7m. depth.
Great Oolite - (mostly lst. but with some Fullers Earth) (404ft. - 123.1m. thickness)
Base of Great Oolite and top of Inferior Oolite - 3500ft. - 1066.8m. depth.
Inferior Oolite - sandy and ferruginous limestones and ironstones - (118ft. - 36m. thickness)
Base of Inferior Oolite and top of Bridport Sands 3618ft - 1102m. depth.
Upper Lias - Bridport Sands - (250ft. - 76.2m. thickness)
Base of Bridport Sands and top of Liassic Clays - 3868ft. - 1179m. depth.
Middle & Lower Liassic Clays - (450ft. - 137m. thickness)
Base of Middle & Lower Liassic Clays and top of Penarth Group (Rhaetic) - 4318ft. - 1316m. depth.
Penarth Group (Rhaetic) - (60ft. - 18.3m. thickness)
Base of Penarth Group and top of Mercia Mudstone (Keuper) - 4378ft. - 1334.4m. depth.
Mercia Mudstone (Keuper) penetrated - (60 feet - 18.3m.)
TD = actual - 4487ft - 1367.6m. (4438ft. - 1352.7m. - calculated on above figures).

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LOCATIONS:

The Marchwood Geothermal Borehole, 1979-1980

- Down to the Budleigh Salterton Pebble Bed!

The 1979 Marchwood Geothermal Borehole, on the eastern shore of Southampton Water, Hampshire

The Marchwood Geothermal Borehole, seen with drilling in progress on a winter's evening, probably in December 1979

Drilling work at the  Marchwood Geothermal Borehole in 1979 continues into the night

Marchwood No.1 and Southampton No.1 borehole logs

A simplified, summary log, with notes, of the 1979, Marchwood Geothermal Borehole No. 1, at the former Marchwood Power Station, Hampshire, near Southampton Water and the New Forest

The uppermost part of the succession in the Composite Log of the 1979-1980, Marchwood Geothermal Borehole No. 1, redrawn by Ian West with some additional notes

The Middle Jurassic part of the succession in the Composite Log of the 1979-1980, Marchwood Geothermal Borehole No. 1, redrawn by Ian West with some additional notes

The Sherwood Sandstone and part of the Mercia Mudstone sequence of the 1979-1980, Marchwood Geothermal Borehole No. 1, redrawn by Ian West with mofications and additions notes

The top of the Budleigh Salterton Pebble Bed is marked by reg or hammada surface with dreikanter or ventifacts, and then the Yellow Bed, west of Budleigh Salterton, Devon, UK

The Marchwood No. 1 Geothermal Borehole was commenced on the 8th November 1979 and completed on the 27th February 1980. It preceded the other geothermal well of the area, which was Southampton No.1 Borehole. That was started on the 26th September 1981, and the well head is located in central Southampton north of the West Quay centre and is in now in the car park of the children toy store - Toys-R-Us.

Thus the Marchwood well was the first geothermal experiment in the region and a drilling rig was put in place so as to be capable of drilling to the Total Depth (T.D.) of 8580 feet (2615m.). The Marchwood and Southampton area is part of a region of high heat flow through the underlying strata. At Southampton the rate is 59 milliwatts per square metre compared to 40mW/m 2 for more northerly parts of Hampshire (Edwards and Freshney (1987). This is almost a 50% increase, and seemed worth exploiting. I was at the Geology Department of Southampton University at the time and followed, to some extent, the progress of both wells. The initial hope was that the Sherwood Sandstone reservoir, a porous red, Triassic sandstone exposed in the Sidmouth to Budleigh Salterton area, would contain hot water at about 100 degrees Centigrade. The usual geothermal gradient is about 30 degrees per kilometre, so that without considering the details, a temperature like this would be expected at round about 3 kilometres. Thus, if the Sherwood Sandstone had been near the total depth of the well, about 2600m, water with a temperature near that of boiling water might have been obtained, and this could have been useful. It was intended to use the heat produced to supplement the energy supply for the Marchwood, coal-fired Power Station, to which the well was adjacent.

However, the Marchwood Borehole, did not produce hot water at this temperature. We shall consider, below, why the temperature was lower than expected. A further complication was that a year or so after the drilling, and for other reasons, the Marchwood Power Station was demolished. Thus, there was no real use nearby for the warm water. However, in spite of the lack of commercial success with regard to geothermal energy, the borehole was certainly a successful research venture. It provided much information on potential oil reservoirs in the area, and particularly helped the understanding of the Bridport Sands, the Upper Reservoir of the Wytch Farm Oil Field.

The Sherwood Sandstone of the Trias was the selected target for hot water. This is because it was the deepest formation in the area that was expected to be sufficiently porous and permeable. This was proved to be the case. An older sandstone, the Devonian Old Red Sandstone lies lower in the borehole sequence, but it is tight, that is, non-porous and non-permeable from a practical point of view. The Sherwood Sandstone can transmit water from a considerable distance and is recharged up-dip in Devon. It should be appreciated, though, that the water is saturated brine. This is because the Trias contains substantial salt deposits in places and some evaporites were proven in the Marchwood Borehole. Even if hot water is pumped from a well it cannot be used directly but has to be directed through stainless steel heat exchangers with the aid of downhole, stainless steel pumps. The brine may also contain heavy metals in solution, and has to be discharged somewhere. The ideal is to have two adjacent boreholes, a production borehole for producing hot water and an injection borehole for disposing of used brine. There was no second borehole at Marchwood. At Southampton Geothermal Well there is only one borehole but the used brine and any associated trace element content is discharged into Southampton Water (already a polluted estuary). Thus the matter is not necessarily simple.

The British Government department, BERR, have commented that the geothermal aquifer resource within the Wessex Basin, under the Bournemouth area, appears to be the most attractive for possible future exploitation, but the commercial risks of speculative drilling remain high. At 3.5p/kWh or more, the cost of heat from the aquifer resource is still significantly higher than that from conventional industrial boilers (approximately 1.44p/kWh). See also Rollin, for more information on low temperature geothermal energy in the UK, including the Wessex Basin.

Returning to specific matters regarding the Marchwood No. 1 borehole, there was, as mentioned above, a problem regarding depth of the geothermal aquifer. The part of interest is the succession from the Lower Greensand downward. It is well-known that there is usually, in this region, a Pre-Albian unconformity at the base of the Gault, and the Basal Gault Pebble Bed is an indication of this. At the base of the Gault in the Marchwood Borehole (depth - 2240ft. - 682.8m.) , the pebble bed does not seem to have been identified (there was coring in the Gault but without recovery). Under the Gault is a very thin sequence of Lower Greensand. It is from 2240ft. to 2267ft.,only 27ft. or 8.2m (compare to the southwestern Isle of Wight where it is, at Atherfield, about 800ft. or 243m.). There is an unconformity, as is common, at the base of the Lower Greensand. It is lying directly on top of Kimmeridge Clay. The Wealden, which can reach more than 600m in the subsurface, is missing. So too is the Purbeck Formation which reaches about 120m. in Durlston Bay. The Portland Stone and Portland Sand is missing. These units can reach about 70m in total thickness. Thus if about the greatest thicknesses could have present, then the Sherwood Sandstone would have been about 790m. lower, although this would have been the extreme. If you add this to the base of the Sherwood Sandstone in Marchwood No. 1 then you obtain 2515m, just a little less than the total depth of the well. Of course the unconformity present means that some of the Kimmeridge Clay is probably missing, and in any case, the Lower Greensand is abnormally thin. A large drilling rig, shown above, was chosen and the plan for drilling the Marchwood Geothermal Borehole was appropriate to deal, if necessary, with a thick Jurassic-Cretaceous sequence including Wealden, Purbeck and Portland. This was a sensible plan, and a reasonably thick sequence was expected so that the Sherwood Sandstone would prove to be deep and hot. It was therefore a disappointment when the unconformity at the base of the LGS was discovered. It was thus possible to use the spare capacity of the drilling rig to penetrate the Devonian and to gain an understanding of the strata below the economic basement (i.e. below the base of the Permo-Trias). So that is why so much Devonian has been drilled. A follow-up to this matter was a similar problem at Southampton No.1 Geothermal Borehole. A fault between the two sites might have led to a deeper succession and higher temperatures, but, in fact, the situation proved to be similar to that at Marchwood. However, at Southampton the geothermal energy could, and is, being put to use (for central heating at Southampton Civic Centre and the South Hants Hospital).

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LOCATIONS:

Lyndhurst - A, Formerly-Proposed, Petroleum Exploration Borehole, Denny Inclosure

Old structure contour map of the White Lias, Penarth Group (Rhaetic) showing a possible oil trap at Denny Inclosure, New Forest, Hampshire

A modified cross-section through the once-proposed (1982) Lyndhurst-A Borehole of Shell UK Ltd at Denny Inclosure, New Forest National Park, Hampshire

Oil exploration has taken place in the New Forest and, as noted above, BP has drilled a well at Hasley Hill in 1959 (Fordingbridge No. 1). It proved to be dry, however, and the interest in oil exploration moved to Dorset, particularly Wytch Farm in the 1970s. Shell UK Ltd. acquired the licence blocks for much of the New Forest. Block PL.181 from Lyndhurst eastward was surveyed seismically using the White Lias, the top of the Penarth Group (Rhaetic) as a good reflector. Look at the map above and you will see that the best high area that seems to have closure (no lateral escape) is where the 4400 and 4300ft contours loop round adjacent to south of a fault. This type of half-dome is very promising for trapping upward-moving oil and gas. It is situated exactly where it would not be welcomed - under the Denny Wood Nature Reserve!

Of course, there was controversy regarding an application to drill in Denny Inclosure, even though the Hasley Hill well seems to have gone through without much argument. There was a Public Inquiry and no permission for drilling was granted. A result of the Public Inquiry is that some interesting information of the subsurface became available at the meeting (see above).

Shown above are maps and a cross-section through the strata beneath Denny Inclosure. The proposed trajectory of the Lyndhurst - A Borehole is shown, on the basis of a diagram on a handout sheet provided by Shell UK Ltd at the time of the Public Inquiry. The diagram has been redrawn in colour and labelled with the probable stratal units that are present. The drawing shows the possibility of oil (and gas?) in all the three main reservoirs of the area. However, it is not know whether anything worthwhile is actually present in any or all of the reservoirs, and the matter remains an interesting open question.

Of the reservoirs, the Sherwood Sandstone Reservoir (Trias) is the important reservoir at Wytch Farm and it the reason that the field is one of the largest onshore oil fields in NW Europe (with nearly 500 million barrels reserves). The Sherwood Reservoir, however, requires that special migrations conditions have enabled hydrocarbons to reach the sandstone, and this may or may not have happened in the New Forest area. The Bridport Sands reservoir is the original reservoir of Wytch Farm and is largely operated by water injection to increase the reservoir pressure. The Great Oolite and possibly adjacent Cornbrash reservoirs are those that have proved successful in the eastern Weald area, as at Humbley Grove, Horndean, Singleton etc. It is not known, of course, whether there is any oil or gas in these potential reservoirs at Denny Inclosure. Conditions might have been unfavourable for migration into the area in Cretaceous time (the general migration date for the region was Cretaceous). The extensional fault which provides closure on the north side might not necessarily be sealing (i.e. oil could have escaped upwards in the Cretaceous). The oil industry probably knows much more now about the likelyhood of oil reserves in this New Forest area, although different companies and different geologists may have varying views. Porosity and permeablility of the reservoirs are interesting aspects that students might wish to consider. Fortunately there is much detailed information on Marchwood No.1, the important borehole at Marchwood Power Station. The log of this should be examined in detail, and any information of Fordingbridge No. 1 and Lockerly No. 1 would be useful. Particular aspects to consider would be the marginal facies changes in the Trias towards the southeast, where it thins out, and the improvement in the reservoir characteristics of the Great Oolite in the same direction.

At the time when Lyndhurst - A was planned deviated wells could be drilled but not laterally from any great distance. Now the new Extended Reach Technology, used so successfully at Wytch Farm to obtain oil at the Goathorn Well from the vicinity of Bournemouth Pier means that most of the New Forest can now be drilled from drilling rigs situated beyond its official limits, or from urban areas within the forest region. If it was thought worth-while and cost-effective the Denny Inclosure prospect could now be drilled by extended reach (i.e. obliquely) from a large rig at Lyndhurst, Ashurst or Marchwood.

(This might be a good topic for student discussion and projects on the future of the New Forest National Park in terms of petroleum geology and petroleum industry. The New Forest has been greatly affected by the petroleum industry in various ways, and even the oil from Wytch Farm passes through it by buried pipeline.)

The diagram that follows shows the locations of the proven oil fields of the central southern England. It also indicates a particular view of Northern Petroleum that there was a migration shadow in the New Forest area. This is a good discussion point - was there as migration shadow in the Cretaceous Period in this area preventing migration of hydrocarbons into the New Forest area? Whether this is right or wrong may affect the New Forest in the future. Should the Denny Inclosure prospect be drilled so at to find out? (Incidently, try to obtain information on the Lymington-Sandhills Fault which is crucial regarding the New Forest).

A map showing th oilfields, gas fields and oil kitchens of the Wessex Basin and the western part to the Weald Basin, southern England, Dorset

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LOCATIONS:

Lymington and New Milton - Petroleum Exploration License - PDL089

Part of the New Forest region near Lymington has been under investigation for petroleum resources by Wessex Exploration Ltd. Details will be found by going to their website at:

Wessex Exploration Limited.

Here is a small extract from the start of the webpage to draw attention to their work. Particularly see the good maps. Note the information on the Hurst Castle Prospect.

"Wessex Exploration Limited, bidding on its own in the 9th Landward Bid Round was awarded Petroleum Exploration and Development License (PEDL) 089 on 4 September, 2000. PEDL 089 is located in southern Hampshire near the towns of Lymington and New Milton, on the mainland opposite the western end of the Isle of Wight. The work obligation for the initial term of the PEDL was met when Northern Petroleum drilled the Bouldnor Copse 1 well, and fifty percent of the PEDL was relinquished in September, 2006. The PEDL is now in its second exploration period.

Wessex on 11 September, 2002 made an "Out of Round" application for a Petroleum Production License over the area immediately offshore from and adjacent to PEDL 089. Wessex was awarded License P1153 over this offshore area, effective 3 October, 2003. The primary term of this license expired in October, 2007, but was renewed by DBERR into a second exploration period.

A preliminary structural map of the Hurst Castle Prospect at the Sherwood Sandstone level is shown on the next page. Estimated P10 oil-in-place is of the order of 190 million barrels for the Sherwood reservoir alone, with possible recoverable reserve of 36 million barrels. A separate structural map shows four-way dip closure offshore, with possible P50 recoverable reserves in the 16 million barrel range." ... [continues]

Hurst Castle Prospect

See the details of the Hurst Castle Prospect.

They report that the Hurst Castle Prospect has potential recoverable reserves of the order of 36 million barrels from the Sherwood reservoir, in a Wytch Farm type fault-block feature. The primary reservoir is the Triassic Sherwood Sandstone. The Bridport Sands is a secondary objective as is the Frome Limestone (Great Oolite). In the same region an exploratory well was drilled at Boulder Copse across the West Solent on the Isle of Wight. The results were negative but Wessex Petroleum did not consider that this impacts on the prospectivity of the Hurst Castle objective.

Note that it is of interest regarding the New Forest National Park that the reservoir objectives are the same as those of Shell at Denny Inclosure (Lyndhurst - A).

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LOCATIONS:

Beaulieu River in the Eastern New Forest
- Ipley Ford

The Beaulieu River at Ipley, a narrow New Forest stream that flows into the much wider estuary of the Beaulieu River, at Beaulieu, Hampshire, seen in normal conditions

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

Evolution of the Beaulieu River System of the southeastern New Forest in the Pleistocene according to Tremlett (1962) - modified diagrams

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LOCATIONS:

Beaulieu River Estuary, south of the New Forest

The head of the Beaulieu River estuary near the sluice at Beaulieu Village, with Fucus on the mudflats and Ian West on the bank, low tide, 12th June 2008

Dieback of Spartina saltmarsh near the main channel, west bank of the Beaulieu River estuary, Hampshire, opposite Exbury, 22nd July 2008

For more information on the Beaulieu Estuary please go to the separate Beaulieu River Estuary webpage.

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LOCATIONS:

Lepe Beach, at the southern end of the New Forest

Rock Armour of Carboniferous Limestone near the Watch House, Lepe Beach, Hampshire

Marls of the Headon Hill Formation on the shore at Lepe Beach, Hampshire

For more information on Lepe Beach geology please go to the separate Lepe Beach and Stone Point webpage.

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LOCATIONS:

Studley Wood, Northern New Forest
with Eocene Exposures

Claypits Bottom north of Studley Wood, New Forest The Latchmoor Brook enters Studley Wood with the Eocene exposures

Studley Wood in the northern part of the New Forest is south of Bramshaw Telegraph, a high point on the B3078 from Cadnam to Fordingbridge. It is one of the few places in the New Forest where fossiliferous deposits can be seen. They are the uppermost Bracklesham Group sediments and the lowermost Barton Clay and are in the banks of the Latchmoor Brook. The exposures are small and in the banks near the stream bed. Fallen trees and slippery, sticky mud are obstacles and Wellington boots are needed. The trees reduce the light for clear visibility, and in winter there may be high water-levels and high flow rates which make access impossible. Nevertheless, in good conditions and with knowledge of the correct locations, three fossiliferous beds can be found. The fossils are only present near stream level because of the decalcification during weathering which has occurred above. It is quite easy to see cream or white shelly material. The aragonitic shells though are crumbly and friable and it is not easy to obtain unbroken specimens. The good collections that have been made have probably been obtained with much care. Without doubt the shells will be in better condition at greater depth.

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LOCATIONS:

Studley Wood
- The Coral Bed of Studley Wood

The Eocene coral bed of Studley Wood, New Forest Glauconitic sediment of the Studley Wood Coral Bed, New Forest

More corals and calcareous worm tubes from the Studley Wood Coral Bed, New Forest A coral from the Studley Wood coral bed, Eocene, New Forest Eocene coral - Paracyathus

The highest of three exposed fossiliferous beds at Studley Wood is the Coral Bed, placed by Todd (1990) in the Elmore Member of the Barton Clay Formation. This bed, as shown above, consists of very sandy clay or argillaceous sand with much glauconite in the sand fraction. The colour varies according to the wetness or dryness of the sediment, the light conditions, the extent of weathering. In the field it seems to be bluish, as shown in the picture, but drying material from the bed seems quite green. A distinctive feature are the large calcareous worm tubes, usually crushed. The corals are surprisingly abundant and may be seen in the field, but the dim light and muddy conditions of the stream bed may not necessarily make this easy. Other shell material, such as remains of bivalves, are present but not conspicuous. This shell debris, as in the associated beds, is still aragonitic. Nearer to the surface the bed is weathered and shell material disappears. The best samples are from about or just above water level of the stream in dry weather when the stream flow is low.

This bed has been briefly described by Stinton (1969) as follows:

"[Unit] C. Coral Bed. Blue, sandy clay with many specimens of an eupsammid coral and large calcareous annelid tubes. 0.45m."

Todd (1990) seems not have seen a good exposure of the Coral Bed. He commented:

"Units SW 2 and 3 [of the Elmore Member of the Barton Clay Formation] represent the 'Huntingbridge Shell Bed', Unit B of Stinton (1970). His 'Coral Bed', unit C was not confidently identified. Notes on the specimen labels from this locality in the British Museum (Natural History) show that at one time he considered it to be merely the upper part of the 'Huntingbridge Bed'. From this and details of the location (Hooker, 1988 pers. comm.) it is probable that the Unit C lies within SW 3B."

Exposures in the stream bed obviously vary from time to time, and back in Victorian times it seems not to have been seen here. It was visible to Stinton in 1970, but may have been obscured when Todd did detailed work there in about 1990. It was easily found at the time of writing (summer 2003), but this is after a prolonged phase of dry weather. In wet weather it may be under water, and almost certainly of difficult access. To see it closely it is in any case necessary to stand in water and soft mud, looking at the east bank, and you are warned of the risk of becoming stuck. You can, however, observe the location of the bed in safety from the top of the west bank of the stream where this brook first enters the wood (adjacent to an old woodbank).

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LOCATIONS:

Studley Wood
- Huntingbridge Shell Bed

The Huntingbridge Shell Bed at Studley Wood

A fault is present, running almost along the direction of the stream, according to Todd (1990) . This fault is not visible but has been detected by augering and detailed studies of the stream. It results in the apparently anomalous occurrence of the Nummulite Bed, discussed below, just downstream of the Coral Bed. In fact the Huntingbridge Shell Bed ought to occur next but part of it is seen a little further south on the east bank. It occurs at the bottom of a little meander cliff. As in the case of the other beds it is decalcified in the bank except at the bottom near stream level. Fragments of common Eocene mollusc shells such as Turritella can soon be recognised. The little exposure resembles a rather weathered bank of the familiar shelly Barton Clay at Highcliffe. It is obvious that a good range of fossil material is present, but good specimens are not immediately found and those seen are fragments in rather crumbly, clayey sand. The present writer has not sytematically collected from here, and thus refers below to the literature regarding species found in this bed. What is shown in the photograph may not necessarily be the best part for shells and better material may be present elsewhere in the stream bed. Note that when the stream level is high access to the bed might be impossible. Like the other exposures, this is a rather dark locality within the wood.

Stinton (1970) described this bed as follows:
"B. Huntingbridge Bed. Dark green, glauconitic, very sandy clay, unfossiliferous above but becoming very fossiliferous below with an abundance of large specimens of Turritella sulcifera Deshayes, Thylacodes ornatus J. de C. Sowerby, Dentalium grande Deshayes and numerous other molluscan species including Bicorbula gallica Lamarck and Spondylus rarispina Deshayes. Thickness - 2 metres. "

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LOCATIONS:

Studley Wood continued
- Nummulite Bed

The Studley Wood Nummulite Bed, New Forest Nummulites and minute bivalves, Eocene, Studley Wood, New Forest

The grey sandy clay of this bed contains many small nummulites, resembling Nummulites variolarius . With these microfossils are minute bivalves, even smaller than the tests of the protozoans. These bivalves are probably a species of Corbula.

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LOCATION:

Eyeworth - Borehole at Captain Schultze's Gunpowder Works

Eyeworth Pond, near Fritham, Hampshire, New Forest National Park, on the Eocene Selsey Formation, photograph 2007

Details are given of a well put down in 1888 on Bracklesham Group at Schultze Gunpowder Co. Works, about 6 miles NW of Lyndhurst, and southwest of Eyeworth Pond. The Gunpowder Factory is shown near the eastern margin of the Geological Survey Sheet, 314, Ringwood, 1902 Edition. There was originally a black powder works established about 1860 and using New Forest charcoal. They were superseded in about 1877 by smokeless powder works, managed by Mr. R.W.S. Griffiths, who was well-known at Fritham (Sumner, 1931 - Latchmore Brook, New Forest). The works were owned by Captain Edward Schultze, an artillary captain in the Prussian Army ( Bramshaw Parish Council - History of the Area). From 1870 it made gunpowder for the Franco-Prussian war. Afterwards its specialised in smokeless powder for sporting guns, until in 1914 and the outbreak of the First World War it was taken over by the British Government. The factory then became a major source of supply of gunpowder to the British troops against the Germans at Flanders. A hundred and forty men were employed in day and night shifts, and they were paid above the average manual worker's wage because of the dangerous work which caused casualties. Fifty horses were used to pull wagons of gunpowder up the specially constructed track, Powder Mill Road, alongside Eyeworth pond and on to Redlynch railway station. Subsequent to the death of Mr. Griffiths the works were closed down in 1919 (information from Mr. R. Bellamy who lived in Fritham for 50 years - from Sumner, 1931)

Most of the building have gone but the manager's house is still there and now called Eyeworth Lodge ( Sibley and Fletcher, 1986). For more information see: New Forest Explorers Guide and Pasmore - New Forest Explosives.

The chemical processing in the factory obviously required a good supply of water. The well described below was an early attempt to solve the water supply problem, but it was not successful. Eyeworth Pond has been made by damming the southwestern end of the Howen Bottom valley, after a successful application to the Deputy Surveyor of the New Forest in 1883 (there had already been a smaller pond for the Black Powder rks). The reservoir supplied water to the factory. However, the outflow from the powder mills polluted the stream water, which flows ultimately to the Latchmore Brook. It killed fish and was said to have prevented salmon coming up New Forest rivers. Cattle apparently refused to drink the water ( Sibley and Fletcher, 1986).

The well refers only to samples at 10 feet intervals but nevertheless gives quite a good record of the Bracklesham Group strata including much of the Selsey Sand Formation and the Earnley, both of which contain glauconitic sands. The pipeclay at the base may be part of the Poole Formation. The record that follows is from Whitaker (1910).

Borehole Record

"From specimens taken at every 10 feet of depth and from information from Mr. R.W.S. Griffiths, Manager.

Shallow pit and then a boring to 200 feet. Very small supply of water, which rose some 60 feet (?more) but was pumped down in a few hours. A little later about 6 feet was silted up.

1. Blackish-brown loamy earth (alluvial wash) (Depth -10ft)
2. Pale brownish or buff clay, slightly sandy. (Depth 20ft.)
3. Dull brown (greyish) clay, or sandy clay. (Depth 30ft)
4. Fine clayey green sand [glauconitic, marine, Bracklesham].(Depth 40ft)
5. Brownish grey sandy clay.(Depth 50ft)
6. Greenish-grey [partly glauconitic] sandy clay or clayey sand.(Depth 60ft)
7. Calcareous stone [probably one of the large round septarian nodule that occur in the Selsey Formation] (2-3 feet) and impure pyrites (?in sand or clay).(Depth 70ft)
8. Fine green [glauconitic] sandy clay or clayey sand. (Depth 80ft)
9. Light grey sandy clay. (Depth 90ft)
10. Light grey sandy clay, more sandy. (Depth 100ft)
11. Pale brownish grey clay. (Depth 110ft)
12. Light-grey clean sand, blowing; gave water at first [running sands occur in the Bracklesham Group in places in the Southampton area]. (Depth 120ft)
13. Dark grey sand, drying compact. (Depth 130ft)
14. Pale brownish-grey sandy clay, with vegetable matter [lignite]. (Depth 140ft)
15. Sand, like 13, but of a lighter colour. (Depth 150ft)
16. Sandy clay, like 14. (Depth 160ft)
17. Sand, like 15. (Depth 170ft)
18. Pale clay, almost a pipe clay [unusual!] (Depth 180ft)
19. Light-brownish grey sand, with pieces of vegetable matter (lignite).(Depth 190ft)
20. Said to be like 19. A heap by the boring, full of pieces of lignite. (Depth 200ft = 61 metres)

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LOCATIONS:

Iron's Well, near Fritham

The chalybeate spring or ochre spring at Iron's Well, Fritham, New Forest, Hampshire, 5th August 2007

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LOCATIONS:

Burley Region

Plateau of Pleistocene river gravel, east of Burley

(text to be added - at present, please go to the section above on Burley Rock)

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BIBLIOGRAPHY AND REFERENCES

Please go to the New Forest Geology Bibliography .

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|Home and Contents |New Forest Geology Bibliography |Solent Bibliograpy - undivided list |Solent Bibliograpy - Topics |Lepe and Stone Point |Beaulieu River Estuary |Calshot Spit and Stanswood Bay

Copyright © 2013 Ian West, Catherine West, Tonya Loades and Joanna West. All rights reserved. This is a purely academic website and images and text may not be copied for publication or for use on other webpages or for any commercial activity. A reasonable number of images and some text may be used for non-commercial academic purposes, including field trip handouts, lectures, student projects, dissertations etc, providing source is acknowledged.

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

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Dr Ian West, author of these webpages

Webpage - written and produced by:


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

.

at his private address, Romsey, Hampshire, kindly supported by Southampton University, and web-hosted by courtesy of iSolutions of Southampton University. The website is an unfunded, private activity, and does not necessarily represent the views of 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.


Ian West rides in the New Forest in winter
.