A Reprint of Annual Reports and Other Papers on the Geology of the Virginias |
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Common terms and phrases
Alumina Alumina and oxide anticlinal Appalachian argillaceous axis band basin beds belt beneath Blue Ridge bluish calcareous Carbonate of lime Carbonate of magnesia character Cheat river clay coal measures coal region coal seams coarse colour compact conglomerate containing creek deposit direction distance district east eastern Eocene Epidote exposed exposures extending feet felspathic ferruginous flexures formation fossils fracture fragments furnace geological Gneiss grains green sand grey hills Hornblende inches James river Kingwood layers limestone localities lower lying magnesia margin marl mass materials matter Mica micaceous middle secondary miles mineral Miocene mountain mouth nearly numerous observations occurs oxide of iron points portion Potomac present quarried quartz region rocks sandstone sandy seen shales shells side Silica slate slaty springs strata stratum structure surface synclinal Talcose Tertiary texture thickness thin tion trace tract upper valley variety veins vicinity Virginia western yellow
Popular passages
Page 745 - A series of sandy, argillaceous, and often calcareous strata, the predominant colour of which is brick-red, but containing portions which are of a greenish grey. These occur often in spots and stripes, so that the series has sometimes been called the variegated sandstone. The European formation so called lies in a geological position immediately above the coal-measures.
Page 744 - A provincial name, adopted in scientific language, for a particular kind of limestone, which, being characterised together with its associated beds, by peculiar fossils, forms a particular group of the secondary strata. Lignite. Wood converted into a kind of coal.
Page 284 - Mica. A simple mineral having a shining silvery surface, and capable Of being split into very thin elastic leaves or scales.
Page 747 - A rock usually containing much magnesian earth, for the most part unstratified, but sometimes appearing to be an altered or metamorphic stratified rock. Its name is derived from frequently presenting contrasts of colour, like the skin of some serpents. SHALE. A provincial term, adopted by geologists, to express an indurated slaty clay. Etym., German schalen, to peal, to split.
Page 635 - ... which will insinuate itself under them, will be raised in their turn, till it either finds some vent or is again condensed by the cold into water, and by that means prevented from proceeding any further.
Page 740 - CARBONATE of LIME. Lime combines with great avidity with carbonic acid, a gaseous acid only obtained fluid when united with water, — and all combinations of it with other substances are called Carbonates. All limestones are carbonates of lime, and quick lime is obtained by driving off the carbonic acid by heat.
Page 167 - This rock, or group of rocks, which is frequently exhibited in extensive exposures along the western side and base of the Blue Ridge, more especially in the middle counties of the valley, is usually a compact, rather fine-grained, white or yellowish gray sandstone. Where resting on the declivity of the ridge, it presents a gentle inclination to the north-west — while the subjacent and more ancient strata of the ridge, in almost every instance, dip steeply to the south-east.
Page 117 - Above and separated by other beds, are two thinner layers of this material, but of an inferior value. Associated with these seams of coal, and lying above the two lower ones, is a bed of limestone of upwards of twenty feet in thickness. At Clarksburg and northward down the valley of the Monongahela, there exists one of the richest coal deposites in the state.