A treatise on geology, the article under that head in the 7th ed. of the Encyclopædia Britannica1837 |
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عبارات ومصطلحات مألوفة
abundance accumulation agencies Alps analogy ancient animals anticlinal appears argillaceous axis basalt basin beds bones brachiopoda calcareous carboniferous chalk changes character chemical circumstances clay coal coast conglomerate considerable convulsions cretaceous crust crustacea deposits depth diluvial dislocations district disturbances earth effects elevation extinct exuviæ fact fault feet fissures formation fossils fresh-water geological geologists globe gneiss granite gravel greensand grit heat igneous rocks islands Isle Isle of Wight lacustrine laminated land lias lime limestone London clay lower Lyell magnesian marine marls mass mica-slate mineral mollusca mountain nature north of England observed occur ocean oolitic oolitic system organic remains parallel particular period phenomena plants porphyry present primary strata ranges red sandstone regions sand sandy sediments shale shells shew silurian similar slate species stone strata stratified rocks subterranean surface temperature tertiary strata thick tion tracts upper vale valley veins volcanic Wealden whole Yorkshire zoophyta
مقاطع مشهورة
الصفحة 267 - ... to act under portions of the earth's crust of considerable extent at any assignable depth, either with uniform intensity at every point, or in some cases with a somewhat greater intensity at particular points; as for instance, at points along the line of maximum elevation of an elevated range, or at other points where the actual phenomena seem to indicate a more than ordinary energy of this subterranean action. I suppose this elevatory force, whatever may be its origin, to act upon the lower...
الصفحة 72 - Phillips remarks, upon an axis of unstratified granitic masses, so as to be inclined at high angles to the horizon. " The great European basin is defined by irregular elevations of this kind from the frozen sea to the Atlantic ; by the Uralian and Caucasian chains, the ranges of Asia Minor, Greece, South Italy, and the Atlas ; the irregular western border of Spain, Ireland, the north of Scotland, and Scandinavia, is of similar structure. Within this area, the Sierras of Spain, the Pyrenees, the Alps,...
الصفحة 270 - ... to the causes to which we have been assigning such phenomena, could not be produced by successive elevations of different points, by the partial action of an elevatory force.
الصفحة 227 - Buffalos (Bison) and other modern animals, many broken, but often quite entire. Beneath this is another thinner layer of a different soil, bearing the appearance of having been formerly the bottom of a marsh. It is more gravelly, darker coloured, softer, and contains remains of reedy plants, smaller than the cane so abundant in some parts of Kentucky, with shells of freshwater Mollusca. In this layer, and sometimes partially imbedded in a stratum of blue clay, very compact and tenacious, are deposited...
الصفحة 293 - ... years : — it is evident that no greater folly can be committed, than to think to serve the cause of truth by contracting the long periods of Geology into the compass of a few thousand years...
الصفحة 12 - ... paribus, the general climate of the earth. Now it is not difficult to show, that this amount is inversely proportional to the minor axis of the ellipse described by the earth about the sun, regarded as slowly variable ; and that, therefore, the major axis remaining, as we know it to be, constant, and the orbit being actually in a state of approach to a circle, and consequently the minor axis being on the increase, the mean annual amount of solar radiation received by the whole earth must be actually...
الصفحة 60 - These escarpments commonly look toward the nearest range of mountains ; in that direction the inclination of the strata augments continually, and at length on the slopes, or in the midst of such mountain range, we find them very steeply inclined, absolutely vertical, partially retroflexed, or bent into strange contortions. " Among the Alps and Pyrenees, the strata, which, in every part of their surface, were originally very little inclined, and which, at a "distance from the mountains, retain nearly...
الصفحة 233 - The connexion of the volcano of Pasto with those of the province of Quito was shown in a striking manner in 1796.