Elements of GeologyJohn Murray, 1838 - 543 Seiten |
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Häufige Begriffe und Wortgruppen
Alps altered ancient aqueous argillaceous augite basalt beds bottom calcareous called carbonate of lime Carboniferous clay coal colour composed composition conglomerate consist containing crag cretaceous crystalline crystals denudation deposits dikes earth earth's crust England Eocene eruptions feet felspar fissures Fitton flint formations fossiliferous strata fossils fragments freshwater genera genus Geol geological geologists gneiss granite green-sand greenstone horizontal hornblende hypogene igneous Inferior Oolite land lava layers Lias limestone lower Magnesian Limestone marine marl mass metamorphic rocks mica mica-schist mineral character mollusca mountain Newer Pliocene observed occur Old Red sandstone organic remains origin pebbles period plants Pliocene plutonic rocks porphyry position quartz resembling rivers sand schist secondary sediment sedimentary seen shale siliceous Silurian slate slaty sometimes species stone strata stratified structure supposed surface syenitic tertiary texture thickness trachyte Trans trap rocks tuff upper veins volcanic rocks Wealden white chalk zoophytes
Beliebte Passagen
Seite 260 - Poets that lasting marble seek Must carve in Latin or in Greek; We write in sand, our language grows, And, like the tide, our work o'erflows.
Seite 73 - Skye, which may be moulded like dough when first found; and some simple minerals, which are rigid and as hard as glass in our cabinets, are often flexible and soft in their native beds ; this is the case with asbestos, sahlite, tremolite, and chalcedony, and it is reported also to happen in the case of the beryl.* The marl recently deposited at the bottom of Lake Superior...
Seite i - For it is a philosophy which never rests, which has never attained, which is never perfect. Its law is progress. A point which yesterday was invisible is its goal to-day, and will be its starting-post to-morrow.
Seite 369 - If it be asked where the continent was placed from the ruins of which the Wealden strata were derived, and by the drainage of which a great river was fed, we are half tempted to speculate on the former existence of the Atlantis of Plato. The story of the submergence of an ancient continent, however fabulous in history, may be true as a geological event.
Seite 104 - The strike, or line of bearing, is the prolongation or extension of the strata in a direction at right angles to the dip ; and hence it is sometimes called the direction of the strata. Thus, in the above instance of strata dipping to the north, their strike must necessarily be east and west. We have borrowed the word from the German geologists, streichen signifying to extend, to have a certain direction. Dip and strike may be aptly illustrated by a row of houses running east and west, the long ridge...
Seite 363 - The regular and uniform preservation of this thin bed of black earth over a distance of many miles, shows that the change from dry land to the state of a freshwater lake or estuary, was not accompanied by any violent denudation, or rush of water, since the loose black earth, together with the trees which lay prostrate on its surface, must inevitably have been swept away had any such violent catastrophe then taken place.
Seite 235 - Herschel, in allusion to slaty cleavage, has suggested, " that if rocks have been so heated as to allow a commencement of crystallization; that is to say, if they have been heated to a point at which the particles can begin to move amongst themselves, or at least on their own axes, some general law must then determine the position in which these particles will rest on cooling. Probably that position will have some relation to the direction in which the beat escapes. Now, when all, or a majority of...
Seite 328 - Kotzebue, stating that the inhabitants of the Radack Archipelago, a group of lagoon islands in the midst of the Pacific, obtained stones for sharpening their instruments by searching the roots of trees which are cast upon the beach. It will be evident that this must have happened several times, since laws have been established that such stones belong to the chief, and a punishment is inflicted on any one who attempts to steal them.
Seite 47 - ... wanting, though occasionally found in a perfect state of preservation in the white chalk at some distance. In this case, we see clearly that the sea-urchin first lived from youth to age, then died and lost its spines, which were carried away. Then the young Crania adhered to the bared shell, grew and perished in its turn ; after which, the upper valve was separated from the lower, before the Echinus became enveloped in chalky mud.
Seite 390 - ... was quite active. Their limbs and strong claws are admirably adapted for crawling over the rugged and fissured masses of lava, which everywhere form the coast. In such situations, a group of six or seven of these hideous reptiles may oftentimes be seen on the black rocks, a few feet above the surf, basking in the sun with outstretched legs.
Verweise auf dieses Buch
Glossary of Geology Klaus K. E. Neuendorf,American Geological Institute Eingeschränkte Leseprobe - 2005 |