Class-book of Geology

abundant abundantly accumulated acid Ammonites basin beds bones bottom Brachiopods calcareous calcite Cambrian carbonate of lime Carboniferous Chapter characteristic chiefly clay containing corals Cretaceous crinoids crystalline crystals decay deposits detritus Devonian earth earth's crust Eocene eruptive rocks Europe evidence example extinct fauna feet thick fishes fissures formations fossils genera geological history geologist glacier globe gneiss gradually granite gravel ground iron Jurassic kinds known lakes land lava layers limestone living lower marine marls mass materials Mesozoic miles Miocene molten mountains natural North occur Old Red Sandstone organic remains original Palæozoic period Permian plants and animals Pliocene present preserved probably quartz rain regions represented rivers sand schists sea-floor sediment sedimentary rocks shales sheets shells siliceous Silurian slopes soil solid sometimes species stone strata stratified stream structure substance surface terrestrial Tertiary trace Triassic Trilobites upper valley various vegetation vent volcanic