In geology

Geology

Geology is the science comprising the study of solid Earth, the rocks of which it is composed, and the processes by which it evolves. Geology gives insight into the history of the Earth, as it provides the primary evidence for plate tectonics, the evolutionary history of life, and past climates...

, the Bagshot Beds are a series of sand

Sand

Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal...

s and clay

Clay

Clay is a general term including many combinations of one or more clay minerals with traces of metal oxides and organic matter. Geologic clay deposits are mostly composed of phyllosilicate minerals containing variable amounts of water trapped in the mineral structure.- Formation :Clay minerals...

s of shallow-water origin, some being fresh-water, some marine. They belong to the upper Eocene

Eocene

The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...

 formation of the London

London Basin

The London Basin is an elongated, roughly triangular sedimentary basin approximately long which underlies London and a large area of south east England, south eastern East Anglia and the adjacent North Sea...

 and Hampshire basins

Hampshire Basin

The Hampshire Basin is a geological basin of Paleogene age in southern England, underlying parts of Hampshire, the Isle of Wight, Dorset, and Sussex...

, in England

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

 and derive their name from Bagshot Heath in Surrey

Bagshot, Surrey

Bagshot is a small town in southeastern England. It is situated in the northwest corner of Surrey within the county's Surrey Heath council district, close to the border with Berkshire, and is also in the diocese of Guildford. In the past Bagshot served as an important staging post between London,...

. They are also well developed in Hampshire

Hampshire

Hampshire is a county on the southern coast of England in the United Kingdom. The county town of Hampshire is Winchester, a historic cathedral city that was once the capital of England. Hampshire is notable for housing the original birthplaces of the Royal Navy, British Army, and Royal Air Force...

, Berkshire

Berkshire

Berkshire is a historic county in the South of England. It is also often referred to as the Royal County of Berkshire because of the presence of the royal residence of Windsor Castle in the county; this usage, which dates to the 19th century at least, was recognised by the Queen in 1957, and...

 and the Isle of Wight

Isle of Wight

The Isle of Wight is a county and the largest island of England, located in the English Channel, on average about 2–4 miles off the south coast of the county of Hampshire, separated from the mainland by a strait called the Solent...

. The following divisions are generally accepted:

• Upper Bagshot Beds — Barton sand and Barton clay
  Barton Beds
  Barton Beds is the name given to a series of grey and brown clays, with layers of sand, of Upper Eocene age , which are found in the Hampshire Basin of southern England. They are particularly well exposed in the cliffs at Barton-on-Sea, which is the world type locality for the Barton Beds, and...
  
  .
• Middle Bagshot Beds — Bracklesham Beds
  Bracklesham Beds
  Bracklesham Beds, in geology, are a series of clays and marls, with sandy and lignitic beds, in the Middle Eocene of the Hampshire Basin, England....
  
  .
• Lower Bagshot Beds — Bournemouth Beds and Alum Bay Beds.

The lower division consists of pale-yellow, current-bedded sand and loam

Loam

Loam is soil composed of sand, silt, and clay in relatively even concentration . Loam soils generally contain more nutrients and humus than sandy soils, have better infiltration and drainage than silty soils, and are easier to till than clay soils...

, with layers of pipeclay and occasional beds of flint

Flint

Flint is a hard, sedimentary cryptocrystalline form of the mineral quartz, categorized as a variety of chert. It occurs chiefly as nodules and masses in sedimentary rocks, such as chalks and limestones. Inside the nodule, flint is usually dark grey, black, green, white, or brown in colour, and...

 pebbles. In the London basin, wherever the junction of the Bagshot beds with the London clay is exposed, it is clear that no sharp line can be drawn between these formations. The Lower Bagshot Beds may be observed at Brentwood

Brentwood, Essex

Brentwood is a town and the principal settlement of the Borough of Brentwood, in the county of Essex in the east of England. It is located in the London commuter belt, 20 miles east north-east of Charing Cross in London, and near the M25 motorway....

, Billericay

Billericay

Billericay is a town and civil parish in the Basildon borough of Essex, England. It lies within the London Basin, has a population of 40,000, and constitutes a commuter town east of central London. The town has three secondary schools and a variety of open spaces...

 and High Beach

High Beach

High Beach also known as High Beech is a hamlet located within Epping Forest. Epping is located to the north east and Central London at Charing Cross lies approximately to the south west.-Description:...

 in Essex

Essex

Essex is a ceremonial and non-metropolitan county in the East region of England, and one of the home counties. It is located to the northeast of Greater London. It borders with Cambridgeshire and Suffolk to the north, Hertfordshire to the west, Kent to the South and London to the south west...

; outliers, capping hills of London clay

London Clay

The London Clay Formation is a marine geological formation of Ypresian age which crops out in the southeast of England. The London Clay is well known for the fossils it contains. The fossils from the Lower Eocene indicate a moderately warm climate, the flora being tropical or subtropical...

, occur at Hampstead

Hampstead

Hampstead is an area of London, England, north-west of Charing Cross. Part of the London Borough of Camden in Inner London, it is known for its intellectual, liberal, artistic, musical and literary associations and for Hampstead Heath, a large, hilly expanse of parkland...

, Highgate

Highgate

Highgate is an area of North London on the north-eastern corner of Hampstead Heath.Highgate is one of the most expensive London suburbs in which to live. It has an active conservation body, the Highgate Society, to protect its character....

 and Harrow

Harrow, London

Harrow is an area in the London Borough of Harrow, northwest London, United Kingdom. It is a suburban area and is situated 12.2 miles northwest of Charing Cross...

. In Surrey, considerable tracts of London clay are covered by heath-bearing Lower Bagshot Beds, as at Weybridge

Weybridge

Weybridge is a town in the Elmbridge district of Surrey in South East England. It is bounded to the north by the River Thames at the mouth of the River Wey, from which it gets its name...

, Aldershot

Aldershot

Aldershot is a town in the English county of Hampshire, located on heathland about southwest of London. The town is administered by Rushmoor Borough Council...

, Woking

Woking

Woking is a large town and civil parish that shares its name with the surrounding local government district, located in the west of Surrey, UK. It is part of the Greater London Urban Area and the London commuter belt, with frequent trains and a journey time of 24 minutes to Waterloo station....

 etc. The Ramsdell

Ramsdell

Ramsdell is a small village in the English county of Hampshire. Ramsdell neighbours with Charter Alley only 1/2 mile up the road. The town of Tadley is away with the nearest shops. Ramsdell lies near other towns the largest being Basingstoke with Newbury only in the other direction...

 clay, N.W. of Basingstoke

Basingstoke

Basingstoke is a town in northeast Hampshire, in south central England. It lies across a valley at the source of the River Loddon. It is southwest of London, northeast of Southampton, southwest of Reading and northeast of the county town, Winchester. In 2008 it had an estimated population of...

, belongs to this formation. In the Isle of Wight, the lower division is well exposed at Alum Bay (660 ft.) and White Cliff Bay (140 ft.). Here it consists of unfossiliferous sands (white, yellow, brown, crimson and every intermediate shade) and clays with layers of lignite

Lignite

Lignite, often referred to as brown coal, or Rosebud coal by Northern Pacific Railroad,is a soft brown fuel with characteristics that put it somewhere between coal and peat...

 and ferruginous sandstone

Sandstone

Sandstone is a sedimentary rock composed mainly of sand-sized minerals or rock grains.Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any colour, but the most common colours are tan, brown, yellow,...

. Similar beds are visible at Bournemouth

Bournemouth

Bournemouth is a large coastal resort town in the ceremonial county of Dorset, England. According to the 2001 Census the town has a population of 163,444, making it the largest settlement in Dorset. It is also the largest settlement between Southampton and Plymouth...

 and in the neighborhood of Poole

Poole

Poole is a large coastal town and seaport in the county of Dorset, on the south coast of England. The town is east of Dorchester, and Bournemouth adjoins Poole to the east. The Borough of Poole was made a unitary authority in 1997, gaining administrative independence from Dorset County Council...

, Wareham

Wareham, Dorset

Wareham is an historic market town and, under the name Wareham Town, a civil parish, in the English county of Dorset. The town is situated on the River Frome eight miles southwest of Poole.-Situation and geography:...

, Corfe Castle and Studland

Studland

Studland is a small village on the Isle of Purbeck in the English county of Dorset. It is famous for its beaches and nature reserve. In 2001 Studland had a population of 480, the lowest in 50 years...

.

The leaf-bearing clays of Alum Bay and Bournemouth are well known and have yielded a large and interesting series of plant remains, including Eucalyptus

Eucalyptus

Eucalyptus is a diverse genus of flowering trees in the myrtle family, Myrtaceae. Members of the genus dominate the tree flora of Australia...

, Caesalpinia

Caesalpinia

Caesalpinia is a genus of flowering plants in the legume family, Fabaceae. Membership within the genus is controversial, with different publications including anywhere from 70 to 165 species, depending largely on the inclusion or exclusion of species alternately listed under genera such as...

, Populus

Poplar

Populus is a genus of 25–35 species of deciduous flowering plants in the family Salicaceae, native to most of the Northern Hemisphere. English names variously applied to different species include poplar , aspen, and cottonwood....

, Platanus

Platanus

Platanus is a small genus of trees native to the Northern Hemisphere. They are the sole living members of the family Platanaceae....

, Sequoia

Sequoioideae

Sequoioideae is a subfamily in the Cupressaceae family, with three genera.-Genera:The three redwood subfamily genera are: Sequoia and Sequoiadendron of California and Oregon, USA; and Metasequoia in China. The redwood species contains the largest and tallest trees in the world. These trees can live...

, Aralia

Aralia

Aralia , or Spikenard, is a genus of the plant family Araliaceae, consisting of 68 accepted species of deciduous or evergreen trees, shrubs, and rhizomatous herbaceous perennials. The genus is native to Asia and the Americas, with most species occurring in mountain woodlands...

, Polypodium

Polypodium

Polypodium is a genus of 75–100 species of true ferns, widely distributed throughout the world, with the highest species diversity in the tropics. The name is derived from Ancient Greek poly "many" + podion "little foot", on account of the foot-like appearance of the rhizome and its branches...

, Osmunda

Osmunda

Osmunda is a genus of primarily temperate-zone ferns of family Osmundaceae. Five to ten species have been listed for this genus.The species have completely dimorphic fronds or pinnae , green photosynthetic sterile fronds, and non-photosynthetic spore-bearing fertile pinnae, with large, naked...

, Nipadites and many others. The clays of this formation are of great value for pottery manufacture; they are extensively mined near Wareham and Corfe, whence they are shipped from Poole and are consequently known as 'Poole clays'. Alum was formerly obtained from the clays of Alum Bay; and the lignite

Lignite

Lignite, often referred to as brown coal, or Rosebud coal by Northern Pacific Railroad,is a soft brown fuel with characteristics that put it somewhere between coal and peat...

s have been used as fuel near Corfe and at Bovey. The Bracklesham Beds

Bracklesham Beds

Bracklesham Beds, in geology, are a series of clays and marls, with sandy and lignitic beds, in the Middle Eocene of the Hampshire Basin, England....

 are sometimes classed with the overlying Barton clay as Middle Bagshot. In the London basin the Barton Beds

Barton Beds

Barton Beds is the name given to a series of grey and brown clays, with layers of sand, of Upper Eocene age , which are found in the Hampshire Basin of southern England. They are particularly well exposed in the cliffs at Barton-on-Sea, which is the world type locality for the Barton Beds, and...

 are unknown. In Surrey and Berkshire, the Bracklesham Beds are from 20 to 50 ft. thick; in Alum Bay they are 100 ft., with beds of lignite in the lower portion; and about here they are sharply marked off from the Barton clay by a bed of conglomerate formed of flint pebbles. The Upper Bagshot Beds, Barton sand and Barton clay, are from 140 to 200 ft. thick in the Isle of Wight. The Agglestone

Agglestone Rock

Agglestone Rock is a sandstone block of about 400 tonnes weight, perched on a conical hill, approximately 1 mile from the village of Studland, south Dorset Legend has it that the devil threw the rock from the Isle of Wight with the intention of hitting Corfe Castle.-Geology:The rock is an "eroded...

 (or Haggerstone) rock and Puckstone rock, near Studland in Dorset

Dorset

Dorset , is a county in South West England on the English Channel coast. The county town is Dorchester which is situated in the south. The Hampshire towns of Bournemouth and Christchurch joined the county with the reorganisation of local government in 1974...

 are formed of large indurated masses of the Lower Bagshot beds that have resisted the weather; Creechbarrow near Corfe is another striking feature due to the same beds. Many of the sarsen

Sarsen

Sarsen stones are sandstone blocks found in quantity in the United Kingdom on Salisbury Plain, the Marlborough Downs, in Kent, and in smaller quantities in Berkshire, Essex, Oxfordshire, Dorset and Hampshire...

 stones or greywethers of S.E. England have been derived from Bagshot strata.