Related by context. Frequent words. (Click for all words.) 70 Late Cretaceous 68 Mesozoic 66 Quaternary 65 Pleistocene 63 Pliocene 62 Carboniferous 62 Eocene 61 Cretaceous 61 Cretaceous Period 61 Paleozoic 61 Proterozoic 60 Ordovician 58 Precambrian 56 interglacial 56 megafauna 56 Oligocene 56 glaciation 55 Holocene 55 volcanism 55 taxa 54 Triassic 54 Jurassic 54 crustal 54 lithosphere 53 hominins 53 magmatic 53 Miocene 53 sediment cores 53 basalts 53 Mammals 52 terrestrial ecosystems 52 fossils 52 landforms 52 theropods 52 lake sediments 51 geologic 51 paleo 51 morphology 51 prehistory 51 sediments 51 morphological 51 Geochemistry 51 diatoms 51 vertebrate 50 hominids 50 fossil 50 sedimentary rocks 50 hominid 50 equatorial 50 Tibetan Plateau 50 speciation 50 Archean 50 Australopithecus 50 igneous 50 tuffs 50 sedimentary rock 50 journal Geology 50 basal 50 Archaea 49 sauropod 49 mass extinctions 49 sedimentary 49 tectonics 49 facies 49 Homo erectus 49 diatom 49 morphologies 49 multicellular 49 seamount 49 Neandertals 49 tectonic 49 Silurian 49 caldera 48 isotopic 48 Little Ice Age 48 Medieval Warm Period 48 hydrothermal 48 hydrothermal alteration 48 Tiktaalik 48 vertebrates 48 Fossils 48 Paleolithic 48 mid latitudes 48 tropics 48 Devonian 48 abundances 48 plate tectonics 48 phylogeny 48 continental drift 47 stratigraphy 47 sauropods 47 intrusive rocks 47 Homo sapiens 47 geologically 47 eukaryotic 47 volcanic rocks 47 biome 47 anomalously 47 Geologically 47 granitic 47 mineralogy