Walks and Talks in the Geological Field

accumulated æon ancient animal anticlinal basin beds bones border bottom bowlders Cambrian carbon Carboniferous Cenozoic clay coal Comstock Lode continued cooling country rock crater creatures Cretaceous crust deep deposits depth Devonian Drift earth earthquake east enormous Eocene Eozoic erosion eruption escape existed feldspar fire-mist fishes fissure formation forms fossil Ganoids geological geyser glacier gneisses granitic gravel hæmatite heat hundred feet inches iron Lake land lava limestone limonite lode lower mammals mass ment Mesozoic miles mineral modern molten moun mountain ocean outcrop Paleozoic Pliocene quartz quartzites region relics remains reptiles rise River rocks rocky salt sand sandstone schists sediments shales sheets shells shore side Silurian slope solid sometimes species stone strata stratified stream structure summit surface synclinal tains teeth temperature Tertiary thick thousand feet tion Triassic Trilobites uplifted upper valley vapor vast volcanic wall wrinkles