shales Definition

schists, graptolitic, clastic, ordovician, basalts, dolomites, carbonates, limestones, hydrocarbons, miocene, siltstone, sedimentary, sedimentary rock, zechstein, sands, granites, diabase, graben, depositional, coal seam, devonian, palaeozoic, stratigraphy, lavas, oligocene, hornfels, diatomite, cretaceous, mudstone, peridotite, paleozoic, carnallite, triassic, paleogene, neocomian, kerogen, sediments, brines, eocene, pegmatites, gabbro, sulphides, geological, claystone, basins, gneiss, paleocene, craton, waterflood, permeabilities, dacite, eluvial, spodumene, palaeocene, magmas, proterozoic, precambrian, diamondiferous, porphyries, halite, porosities, eudialyte, natural gas, anticlines, kaolinite, pelite, greywacke, gravels, anticline, sylvite, silurian, geology, evaporite, upper carboniferous, turonian, alluvium, mississippian, phyllosilicate, wells, hornblende, bituminous coal, drilling, gossan, archean, pyroxenite, ostracod, chalcocite, andesite, adularia, syenite, calcic, dunite, molybdenum, bornite, sandstone, sericite, stratiform, archaean, silicates, footwall,