Related by context. Frequent words. (Click for all words.) 55 Younger Dryas 54 Late Cretaceous 54 marine sediments 53 foraminifera 53 Cambrian explosion 53 Quaternary 53 Pliocene 52 Paleocene 52 solar nebula 52 Precambrian 52 stromatolites 51 lithosphere 51 Carboniferous 51 basaltic 50 interglacial 50 Ordovician 50 lavas 49 spherules 49 supercontinent 49 sedimentary rock 49 oceanic crust 49 Eocene 49 diatom 49 interglacial period 49 igneous 48 morphologically 48 zircons 48 microfossils 48 Cretaceous 48 ejecta 48 mudstone 48 volcanism 48 Paleozoic 48 mid latitudes 47 calcite 47 glaciation 47 magmatic 47 Antarctic ozone 47 Proterozoic 47 multicellular 46 Mesozoic 46 Supplementary Fig 46 abiotic 46 Pleistocene 46 basalts 46 regolith 46 trilobites 46 geologic 46 lake sediments 45 continental crust 45 Cretaceous Period 45 terrestrial ecosystems 45 isotopic 45 tuffs 45 lava flows 45 Triassic 45 Burgess Shale 45 ocean ridges 45 Oligocene 45 radioactive decay 45 abundances 45 oxygen isotopes 45 crustal 44 diatoms 44 landforms 44 Lower Cretaceous 44 marine invertebrates 44 olivine 44 geologically 44 Meridiani 44 sediments 44 sedimentary rocks 44 stalagmite 44 depositional 43 thermosphere 43 volcanic 43 morphologies 43 surficial 43 magnetar 43 atmospheric methane 43 Miocene 43 journal Geology 43 apatite 43 calcareous 43 graben 43 Iapetus 43 prokaryotes 43 silicates 43 permafrost 43 Silurian 43 isoprene 43 earth crust 43 Medieval Warm Period 42 lithology 42 methane hydrates 42 H. erectus 42 volcanically active 42 subduction zones 42 plate tectonics 42 Weddell Sea 42 mass extinction