The Quarterly Journal of the Geological Society of London, Volumen2Longman, Green, Longman, Roberts, & Green, 1846 |
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Términos y frases comunes
Alum Bay angle animals appears argillaceous basin beds belong bones boulders calcareous carboniferous chalk character cleavage coal coal-field coal-measures colour conglomerate Coniston Coniston limestone containing Cyrena deposits described Devonian east elevation Eocene exhibited existing fault fauna feet thick formation fossils freshwater genera genus geologists granite gravel greensand greenstone grey grits humerus igneous rocks inches island Isle of Wight limestone Littry London clay Lower Silurian Lyell marine marls mass memoir miles mountain Murchison nearly north-east northern nummulitic observed occur Old red old red sandstone organic remains palæozoic Pecopteris period phænomena plants plates porphyry portion present quarry red sandstone remarkable resembling ridge river Russia sand schists seams shale shells side Sigillaria Silurian rocks slate slaty species specimens Stigmariæ strata striæ surface tertiary tion traced valley vertical volcanic Wales Wealden Wenlock White Cliff Bay whole
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Página 220 - A work of immense labour and research Nothing has ever appeared in lithography in this country at all comparable to these plates : and as regards the representations of minute osseous texture, by Mr. Ford, they are perhaps the most perfect that have yet been produced in any country. . . . The work has commenced with the Elephant group, in which the authors say ' is most signally displayed the numerical richness of forms which characterises the Fossil Fauna of India ;' and the first chapter relates...
Página 101 - England of his day, whatever its limitations, was seething with important movements as interesting, in slightly different applications, on this side of the Atlantic as well as on the other...
Página 284 - ... shale that, in the neighbouring districts of mountain limestone, is found in the lower part of that formation.
Página 170 - That coal-field, comprehending parts of Illinois, Indiana, and Kentucky, is not much inferior in dimensions to the whole of England, and consists of horizontal strata, with numerous rich seams of bituminous coal.
Página 194 - The old and weathered shells left on the surface of the upraised plain still partially retain their colours. The uprising movement has been interrupted by at least eight long periods of rest, during which the sea ate deeply back into the land, forming at successive levels the long lines of cliffs or escarpments, which separate the different plains as they rise like steps one behind the other. The...
Página 160 - Murchison from this chair four years ago*, where he states, that the conventional line that had been drawn between the Lower Silurian and the Cambrian rocks beneath them had no longer any reference to strata identified by distinguishing organic remains, for the same fossils are found in strata on each side of that demarcation. He also stated on the same occasion, that "the zone of fossiliferous strata characterized by the Lower Silurian Orthidae are the oldest beds in which organic life has been...
Página 198 - that in order to depress or elevate the absolute level of the sea, by a given quantity, in any one place, we must depress or elevate it by the same quantity over the whole surface of the earth ; whereas no such necessity exists with respect to the elevation or depression of the land...
Página 130 - A Report to the Navy Department of the United States on American Coals, Applicable to Steam Navigation, and to other purposes.
Página 51 - Downs' (p. 76). The specimens collected from these localities consist of waterworn fragments of stems and branches, which are generally more or less perforated by boring mollusca. The structure of the wood is decidedly coniferous ; transverse sections present concentric circles and medullary rays, and a reticulated surface composed of distinct cellules, varying in form from the circular to the elliptical. In a longitudinal division the tubes or woody fibres are seen to be uniform, and to have their...
Página 19 - Middle coal-measures. miuates in two singular rounded projections, which have evidently been pushed up by the underlying strata. It is succeeded by about one yard of red clays, which bear evidence of considerable pressure having been exerted upon them. Then come regular coal-measures, dipping SSW at angles varying from 80° to 70°. These last-named strata are in the lower part of the middle coal-field ; the whole of the thick beds of this valuable deposit being here covered up by the upper new red...