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LIAS

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Originally appearing in Volume V16, Page 534 of the 1911 Encyclopedia Britannica.
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LIAS , in See also:

geology, the lowermost See also:group of See also:Jurassic strata. Originally the name seems to have been written " Lyas "; it is most probably a provincial See also:form of ." layers," strata, employed by quarrymen in the See also:west of See also:England; it has been suggested, however, that the Fr. liais, See also:Breton leach= a See also:stone, Gaelic leac = a See also:flat stone, may have given rise to the See also:English " Lies." Liassic strata occupy an important position in England, where they See also:crop out at Lyme Regis on the See also:Dorsetshire See also:coast and extend thence by See also:Bath, along the western flank of the Cotswold Hills, forming Edge See also:Hill and appearing at See also:Banbury, See also:Rugby, Melton, See also:Grantham, See also:Lincoln, to See also:Redcar on the coast of See also:Yorkshire. They occur also in See also:Glamorganshire, See also:Shropshire, near See also:Carlisle, in See also:Skye, Raasay (Pabba, Scalpa and Broadfoot beds), and elsewhere in the See also:north of See also:Scotland, and in the north-See also:east of See also:Ireland. East of the See also:belt of outcrop indicated, the Lias is known to occur beneath the younger rocks for some distance farther east, but it is absent from beneath See also:London, See also:Reading, See also:Ware, See also:Harwich, See also:Dover, and in the See also:southern portion of the See also:area in which these towns See also:lie; the Liassic rocks are probably thinned out against a concealed See also:ridge of more See also:ancient rocks. The table on following See also:page will serve to illustrate the See also:general characters of the English Lias and the subdivisions adopted by the See also:Geological Survey: By the See also:side are shown the See also:principal zonal See also:ammonites, and, for comparison, the subdivisions preferred by Messrs See also:Tate and See also:Blake and by A. de See also:Lapparent. The important fact is clearly demonstrated in the table, that where the Lies is seen in contact with the Trias below or the Inferior ()elite above, there is, as a See also:rule, a See also:gradual passage from the Liassic formation, both downwards and upwards; hence See also:Professor de Lapparent includes in his Liassique See also:System the See also:zone of Ammonites opalinus at the See also:top, and the See also:Rhaetic beds at the bottom (see OoLITE; RHAET1C). Owing to the transgression of the Liassic See also:sea the strata See also:rest in places upon older Palaeozoic rocks. The thickness of the Lias varies considerably; in Dorsetshire it' is 90o ft., near Bath it has thinned to 280 ft., and beneath See also:Oxford it is further reduced. In north See also:Gloucester-See also:shire it is 136o ft., See also:Northampton 76o ft., See also:Rutland 800 ft., Lincoln-shire 950 ft., and in Yorkshire about 500 ft. The Lias of England was laid down in conditions very similar to those which obtained at the same See also:time in north See also:France and north See also:Germany, that is to say, on the See also:floor of a shallow sea; but in the Alpine region limestones are See also:developed upon a much greater See also:scale. Many of the limestones are red and crystalline See also:marbles such as the " ammonitico-rosso-inferiore " of the See also:Apennines; a See also:grey, laminated See also:limestone is known as the Fleckenmergel." The whitish " Hierlatzkalke," the Adnet beds and the " Grestener beds" in the eastern See also:Alps and See also:Balkan Mountains are important phases of Alpine Lias. The Grestener.beds contain a considerable amount of See also:coal.

The Lias of See also:

Spain and the See also:Pyrenees contains much dolomitic limestone. This formation is widely spread in western See also:Europe; besides the localities already cited it occurs in See also:Swabia, the Rhenish provinces, See also:Alsace-See also:Lorraine, See also:Luxemburg, See also:Ardennes, See also:Normandy, See also:Austria-See also:Hungary, the Balkan States, See also:Greece'and Scania. It has not been found north of See also:Kharkov in See also:Russia, but it is See also:present in the See also:south and in the See also:Caucasus, in See also:Anatolia, See also:Persia and the Himalayas. It appears on the eastern side of See also:Japan, in See also:Borneo, See also:Timor, New See also:Caledonia and New See also:Zealand (See also:Bastion beds); in See also:Algeria, See also:Tunisia and elsewhere in North See also:Africa, and on the west coast of See also:Madagascar. In South See also:America it is found in the Bolivian See also:Andes, in See also:Chile and See also:Argentina; it appears also on the Pacific coast of North America. of See also:March 1J73. After his See also:death See also:Pibrac, 'assisted by De 'See also:Thou and Scevole de Sainte-Marthe, collected a See also:volume of the Poemata of L'H8pital', and in 1585 his See also:grandson published Epistolarum seu Sermonum libri See also:sex. The See also:complete IEuvres de l'Hopital were published for the first time by P. J.S. Dufey (5 vols., See also:Paris, 1824-1825), They include his " Harangues " and " Remonstrances," the Epistles, the M.emoire to See also:Charles IX., a Traiti de la See also:reformation de la See also:justice,'hnd'his'ivill. See also A. F.

See also:

Villemain, See also:Vie du Chancelier de l'llepital.(Parisi 1874) ; R. G. E. T. St-Rene See also:Taillandier, Le Channcelier de l'Hospittalf (Paris, 1861); See also:Dupre-See also:Lasalle, See also:Michel de l'See also:Hospital avant son See also:elevation an poste de chancelier de France (Paris, 1875-1899) ; Amphoux, Mickel de l'Hospital et la liberte de See also:conscience an "X VP siecle (Paris, 19oo) ; C. T. See also:Atkinson, Michel de l'Hospital (London, 1900), containing an appendix on bibliography and See also:sources; A. ,E. See also:Shaw, Michllde !'Hospital and his Policy (London, 1910,5); and See also:Eugene and Emile Haag, La Franceprotestanle (and ed., 1877 seq.). The economic products of the Lias are of considerable importance. In the See also:Lower Lias of See also:Lincolnshire and the See also:Middle Lias of See also:Oxfordshire, See also:Northamptonshire, Lincolnshire, See also:Leicestershire and Yorkshire the beds of ironstone are of See also:great value. Most of these ores are limestones that have been converted into See also:iron carbonate with some admixture of silicates; they See also:weather near the See also:surface into hydrated peroxide.

He removed his school to See also:

Nicomedia, where he remained five years. After another See also:attempt to See also:settle in See also:Constantinople, he finally retired to See also:Antioch (354)• Though a See also:pagan, he enjoyed the favour of the See also:Christian emperors. When See also:Julian, his See also:special See also:patron, restored paganism as the See also:state See also:religion, See also:Libanius showed S.W. England and Midlands. Yorkshire. Ammonite Zones.' DA. de according to A. de Lapparent.2 a Midford Sands (passage beds) See also:Alum shale Am. jurensis tT' (Including the opalinus zone ~-a See also:Clays with See also:Cement-stones See also:Jet See also:Rock „ communis of the Inferior Oolite.) Limestones and Clays Grey Shale „ serpentinus Toarcien. „ annulatus 6 Marlstone and Sands Ironstone See also:Series Am. spinatus M Charmouthien. S.a (Rock See also:Bed and Ironstones) Sandy Series „ margaritatus L Micaceous Clays and Sands 1 1. Clays with occasional bands Upper Series with Am. See also:capricornus o of Limestone Ironstone nodules „ Jamesoni Limestones and Clays Lower Series with and Sandy and Marly armatus Beds „ oxynotus „ Bucklandi „ angulatus planorbis Sinemourien. Hettangien including "See also:White Lias." Rhetien. 1 The brackets indicate the divisions made by R. Tate and J.

F. Blake. 2 Traite de geologie (5th ed., Paris, 1906). At Frodingham in Lincolnshire the oolitic iron ore reaches 30 ft. in thickness, of which 12 ft. are workable. In See also:

Gloucestershire the top beds of the Lower Lias and lower beds of the Middle See also:division are the most ferruginous; the best ores near See also:Woodstock and Banbury and between See also:Market Harborough and See also:Leicester are at the See also:summit of the Middle Lias in the Marlstone or Rock bed. The ironstone of Fawler is sometimes known as See also:Blenheim ore. The ores of the Cleve-See also:land See also:district in Yorkshire have a great reputation; the See also:main seam is I1 ft. thick at See also:Eston, where it rests directly upon the Pecten Seam, the two together aggregating 15 ft. 6 in. Similar iron ores of this See also:age are worked at Meurthe-et-Moselle, Villerupt, Marbache, Longuy, Champagneulles, &c. Some of the Liassic limestones are used as See also:building stones, the more important ones being the Lower Lias See also:Sutton stone of Glamorganshire and Middle Lias Hornton stone, the best of the Lias building stones, from Edge Hill. The limestones are often used for paving. The limestones of the Lower Lias are much used for the See also:production of See also:hydraulic cement and " See also:Blue Lias " See also:lime at Rugby, See also:Barrow-on-Soar, Barnstone, Lyme Regis, Abertham and many other places.

See also:

Roman cement has been made from the nodules in the Upper Lias of Yorkshire; alum is obtained from the same See also:horizon. A considerable See also:trade was formerly done in jet, the best quality being obtained from the " Serpentinus " beds, but " See also:bastard " or soft jet is found in many of the other strata in the Yorkshire Lias. Both Lower and Upper Lias clays have been used in making bricks and tiles. Fossils are abundant in the Lias; Lyme Regis, Shepton See also:Mallet, Rugby, See also:Robin See also:Hood's See also:Bay, Ilminster, See also:Whitby and See also:Golden Cap near Charmouth are well-known localities. The saurian See also:reptiles, See also:Ichthyosaurus and See also:Plesiosaurus, are found in excellent preservation along with the Pterodactyl. Among the fishes are Hybodus, Dapedius, Pholidophorus, Acrodus. The crinoids, Pentacrinus and Extracrinus are locally abundant. See also:Insect remains are very abundant in certain beds. Many ammonites occur in this formation in addition to the forms used as zonal indexes mentioned in the table. See also:Lima gigantea, Posidonomya Bronni, Inoceramus dubius, Gryphaea cymbium and G. arcuala are See also:common pelecypods. Amberleya capitanea, Pleurotomaria anglica are Lias gasteropods. Leptaena, Spiriferina, Terebratella and Rhynchonella tetrahedra and R. variabilis are among the brachiopods.

Certain dark limestones with See also:

regular bedding which occur in the Carboniferous System are sometimes called " See also:Black Lias " by quarrymen. See The Lias of England and See also:Wales " (Yorkshire excepted), by H. B. See also:Woodward, Geol. Survey Memoir (London, 1893); and, for Yorkshire, " The Jurassic Rocks of See also:Britain,” vol. i., " Yorkshire,” by C. See also:Fox-Strangways, Geol. Survey Memoir. See also JURASSIC. (J. A.

End of Article: LIAS

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