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GREENSAND , in See also:geology, the name that has been applied to no fewer than three distinct members of the Cretaceous See also:System, viz. the Upper Greensand (see See also:GAULT), the See also:Lower Greensand and the so-called See also:Cambridge Greensand, a See also:local phase of the See also:base of the See also:Chalk (q.v.). The See also:term was introduced by the See also:early See also:English geologists for certain sandy rocks which frequentlyexhibited a greenish See also:colour on See also:account of the presence of See also:minute grains of the See also:green See also:mineral See also:glauconite. Until the fossils of these rocks came to be carefully studied there was much confusion between what is now known as the Upper Greensand (Selbornian) and the Lower Greensand. Here we shall confine our See also:attention to the latter.
The Lower Greensand was first examined in detail by W. H. See also:Fitton (Q.J.G.S. iii., 1847), who, in 1845, had proposed the name " Vectine " for the formation. The name was revived under the See also:form " Vectian " in 1885 by A. J. See also:Jukes-See also:- BROWNE
- BROWNE, EDWARD HAROLD (18,1–1891)
- BROWNE, ISAAC HAWKINS (1705-1760)
- BROWNE, JAMES (1793–1841)
- BROWNE, MAXIMILIAN ULYSSES, COUNT VON, BARON DE CAMUS AND MOUNTANY (1705-1757)
- BROWNE, PETER (?1665-1735)
- BROWNE, ROBERT (1550-1633)
- BROWNE, SIR JAMES (1839–1896)
- BROWNE, SIR THOMAS (1605-1682)
- BROWNE, WILLIAM (1591–1643)
- BROWNE, WILLIAM GEORGE (1768-1813)
Browne, because, although sands and sandstones prevail, the green colour has often changed by oxidation of the See also:iron to various shades of red and See also:- BROWN
- BROWN, CHARLES BROCKDEN (1771-181o)
- BROWN, FORD MADOX (1821-1893)
- BROWN, FRANCIS (1849- )
- BROWN, GEORGE (1818-188o)
- BROWN, HENRY KIRKE (1814-1886)
- BROWN, JACOB (1775–1828)
- BROWN, JOHN (1715–1766)
- BROWN, JOHN (1722-1787)
- BROWN, JOHN (1735–1788)
- BROWN, JOHN (1784–1858)
- BROWN, JOHN (1800-1859)
- BROWN, JOHN (1810—1882)
- BROWN, JOHN GEORGE (1831— )
- BROWN, ROBERT (1773-1858)
- BROWN, SAMUEL MORISON (1817—1856)
- BROWN, SIR GEORGE (1790-1865)
- BROWN, SIR JOHN (1816-1896)
- BROWN, SIR WILLIAM, BART
- BROWN, THOMAS (1663-1704)
- BROWN, THOMAS (1778-1820)
- BROWN, THOMAS EDWARD (1830-1897)
- BROWN, WILLIAM LAURENCE (1755–1830)
brown, and other lithological types, See also:clays and limestones represent this See also:horizon in certain areas. The Lower Greensand is typically See also:developed in the See also:Wealden See also:district, in the Isle of See also:Wight, in See also:Dorsetshire about See also:Swanage, and it appears again beneath the See also:northern outcrop of the Chalk in See also:Berkshire, See also:- OXFORD
- OXFORD, EARLS OF
- OXFORD, EDWARD DE VERE, 17TH EARL
- OXFORD, JOHN DE VERE, 13TH EARL OF (1443-1513)
- OXFORD, PROVISIONS OF
- OXFORD, ROBERT DE VERE, 9TH EARL OF (1362-1392)
- OXFORD, ROBERT HARLEY, 1ST
Oxford-See also:shire and See also:Bedfordshire, and thence it is traceable through See also:Norfolk and See also:Lincolnshire into See also:east See also:Yorkshire. It rests conform-ably upon the Wealden formation in the See also:south of See also:England, but it is clearly separable from the beds beneath by the occurrence of marine fossils, and by the fact that there is a marked overlap of the Lower Greensand on the See also:Weald in See also:Wiltshire, and derived pebbles are found in the basal beds. The whole See also:series is 800 ft. thick at Atherfield in the Isle of Wight, but it thins rapidly westward. It is usually clearly marked off from the overlying Gault.
In the Wealden See also:area the Lower Greensand has been sub-divided as follows, although the several members are not every-where recognizable:
Isle of Wight.
See also:Folkestone Beds (7o-too ft.) . Carstone and See also:Sand See also:rock series. See also:Sandgate Beds (75-too ft.) . Ferruginous Sands (See also:Shanklin sands). See also:Hythe Beds (80-30o ft.) . Ferruginous Sands (Walpen sands). Atherfield See also:Clay (2o-90 ft.). . Atherfield Clay.
The Atherfield Clay is usually a sandy clay, fossiliferous. The basal portion, 5-6 ft., is known as the " Perna See also:bed " from the abundance of Perna Mulleti; other fossils are Hoplites Deshayesii, Exogyra sinuata, Ancyloceras Mathesonianum. The Hythe beds are interstratified thin limestones and sandstones; the former are bluish-See also:grey in colour, compact and hard, with a certain amount of See also:quartz and glauconite. The See also:limestone is known locally as " rag "; the Kentish Rag has been largely employed as a See also:building See also:- STONE
- STONE (0. Eng. shin; the word is common to Teutonic languages, cf. Ger. Stein, Du. steen, Dan. and Swed. sten; the root is also seen in Gr. aria, pebble)
- STONE, CHARLES POMEROY (1824-1887)
- STONE, EDWARD JAMES (1831-1897)
- STONE, FRANK (1800-1859)
- STONE, GEORGE (1708—1764)
- STONE, LUCY [BLACKWELL] (1818-1893)
- STONE, MARCUS (184o— )
- STONE, NICHOLAS (1586-1647)
stone and roadstone; it frequently contains layers of chert (known as See also:Sevenoaks stone near that See also:town). The sandy portions are very variable; the stone is often clayey and calcareous and rarely hard enough to make a See also:good building stone; locally it is called " hassock " (or Calkstone). The two stones are well exposed in the See also:Iguanodon See also:Quarry near See also:Maidstone (so called from the See also:discovery of the bones of that reptile). South-See also:west of See also:Dorking See also:sandstone and grit become more prevalent, and it is known there as " Bargate stone," much used around See also:Godalming. Pulborough stone is another local sandstone of the Hythe beds. See also:Fuller's See also:earth occurs in parts of this formation in See also:Surrey. The Sandgate beds, mainly dark, argillaceous sand and clay, are well developed in east See also:Kent, and about See also:Midhurst, Pulborough and Petworth. At Nutfield the celebrated fuller's earth deposits occur on this horizon; it is also found near Maidstone, at Bletchingley and Red See also:- HILL
- HILL (0. Eng. hyll; cf. Low Ger. hull, Mid. Dutch hul, allied to Lat. celsus, high, collis, hill, &c.)
- HILL, A
- HILL, AARON (1685-175o)
- HILL, AMBROSE POWELL
- HILL, DANIEL HARVEY (1821-1889)
- HILL, DAVID BENNETT (1843–1910)
- HILL, GEORGE BIRKBECK NORMAN (1835-1903)
- HILL, JAMES J
- HILL, JOHN (c. 1716-1775)
- HILL, MATTHEW DAVENPORT (1792-1872)
- HILL, OCTAVIA (1838– )
- HILL, ROWLAND (1744–1833)
- HILL, SIR ROWLAND (1795-1879)
Hill. The Folkestone beds are See also:light-coloured, rather coarse sands, enclosing layers of siliceous limestone (Folkestone stone) and See also:chest; a phosphatic bed is found near the See also:top. These beds are well seen in the cliffs at Folkestone and near See also:Reigate. At Ightham there is a See also:fine, hard, See also:- WHITE
- WHITE, ANDREW DICKSON (1832– )
- WHITE, GILBERT (1720–1793)
- WHITE, HENRY KIRKE (1785-1806)
- WHITE, HUGH LAWSON (1773-1840)
- WHITE, JOSEPH BLANCO (1775-1841)
- WHITE, RICHARD GRANT (1822-1885)
- WHITE, ROBERT (1645-1704)
- WHITE, SIR GEORGE STUART (1835– )
- WHITE, SIR THOMAS (1492-1567)
- WHITE, SIR WILLIAM ARTHUR (1824--1891)
- WHITE, SIR WILLIAM HENRY (1845– )
- WHITE, THOMAS (1628-1698)
- WHITE, THOMAS (c. 1550-1624)
white sand-stone along with a green, quartzitic variety (Ightham stone). In See also:Sussex the limestone and chert are usually lacking, but a ferruginous grit, " carstone," occurs in lenticular masses and layers, which is used for road See also:- METAL
- METAL (through Fr. from Lat. metallum, mine, quarry, adapted from Gr. µATaXAov, in the same sense, probably connected with ,ueraAAdv, to search after, explore, µeTa, after, aAAos, other)
metal at Pulborough, Fittleworth, &c.
The Lower Greensand usually forms picturesque, healthy See also:country, as about See also:Leith Hill, Hindhead, Midhurst, Petworth, at See also:Woburn, or at Shanklin and See also:Sandown in the Isle of Wight. Outside the See also:southern area the Lower Greensand is represented by the See also:Faringdon sponge-bearing beds in Berkshire, the Sandy and
Potton beds in Bedfordshire, the Shotover iron sands of Oxford-shire, the sands and fuller's earth of Woburn, the See also:Leighton See also:Buzzard sands, the See also:brick clays of Snettisham, and perhaps the See also:Sandringham sands of Norfolk, and the carstone of that See also:county and Lincolnshire. The upper ironstone, limestone and clay of the Lincolnshire Tealby beds appear to belong to this horizon along with the upper See also:part of the Speeton beds of Yorkshire. The sands of the Lower Greensand are largely employed for the manufacture of See also:glass, for which purpose they are dug at See also:Aylesford, Godstone, neat Reigate, Hartshill, near See also:Aylesbury and other places; the ferruginous sand is worked as an iron ore at Seend.
This formation is continuous across the channel into See also:France, where it is well developed in Boulonnais. According to the See also:continental See also:classification the Atherfield Clay is See also:equivalent to the Urgonian or Barremian; the Sandgate and Hythe beds belong to the See also:Aptian (q.v.); while the upper part of the Folkestone beds would fall within the lower See also:Albian (q.v.).
See the See also:Memoirs of the See also:Geological Survey, " Geology of the Weald " (1875), " Geology of the Isle of Wight " (2nd ed., 1889), " Geology of the Isle of Purbeck " (1898); and the See also:Record of Excursions, Geologists' Association (See also:London, 1891). (J. A.
End of Article: GREENSAND
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