agglomerate alabaster anthracite asbestos atoll basalt basin bauxite bed bedrock beryl bluff canyon cape carboniferous chalk chalky chasm clay cliff coal coastal coastline conglomerate continental drift continental shelf core cove crag crater creek Cretaceous crevasse crust crystal crystalline crystallize delta deposit deposition dune dust bowl earthquake elevation emery epicentre epoch era erode erosion erupt escarpment estuary extinct fault feeder feldspar fiord fjord flint flood plain fluvial fold fool's gold fossil fossilize friable geology(n) geyser glaciation glacier geology(n) Gondwanaland granite grassland groundwater gulf gully headland hinterland hot spring igneous impervious inactive inlet isthmus jasper jet kaolin knoll lagoon lake landlocked landslide landslip lava leach levee lime limestone loam lowlands magma marble marsh marshland matrix mica mineral mineralogy mining moraine morass mountain mountainside mountaintop mudslide nugget oasis oilfield ore outcrop palaeontology Pangaea peninsula permafrost petroleum pillar pinnacle plate plate tectonics porous pothole prairie precipice promontory pumice pyrites quartz ravine reservoir ridge rift rift valley river rock rock salt sand sand bar sandstone sapphire scarp schist scree seam sediment sedimentary sedimentation seismic seismograph seismology settlement shale shelf shingle silica silicate silt slate stalactite stalagmite stone strait stratified stratum subsoil substratum summit terrain thermal topaz topsoil tor tremor tributary trilobite tsunami tundra turquoise valley vein volcanic volcano watercourse waterfall water table