Related by context. Frequent words. (Click for all words.) 71 marine sediments 63 microfossils 62 sediment cores 61 lavas 61 sediments 60 hydrothermal vent 60 Arctic permafrost 59 geological formations 59 lake sediments 59 sedimentary rock 58 basalts 58 atmospheric methane 57 oceanic crust 57 foraminifera 57 Weddell Sea 57 isotopic composition 57 Valles Marineris 56 Burgess Shale 56 Sediments 56 geologic formations 56 lithosphere 56 stromatolites 56 hydrothermal activity 56 earth crust 56 seabeds 56 continental crust 56 permafrost 55 geologic 55 ocean ridges 55 biota 55 oxygen isotopes 55 sediment 55 zircons 55 Saturn moon Enceladus 55 methane hydrates 55 methane hydrate 55 terrestrial ecosystems 55 magma chamber 55 lava tubes 54 solar nebula 54 lunar soil 54 subsurface 54 crustal 54 biogeochemical 54 retreating glaciers 54 hydrothermal vents 54 Tibetan Plateau 54 aerosol particles 54 volcanism 54 sedimentary basins 54 sediment samples 53 coprolites 53 temperate forests 53 seafloor 53 landforms 53 diatoms 53 depositional 53 geologically active 53 icy crust 53 stalagmite 53 Earth crust 53 deplete oxygen 53 Ordovician 53 gas hydrates 53 bathymetry 53 carbonate rocks 53 mid latitudes 53 osmium 52 microscopic organisms 52 geomorphology 52 Cyanobacteria 52 Martian rocks 52 headwater streams 52 sedimentary 52 Late Cretaceous 52 mudstone 52 biodiversity hotspot 52 seabed 52 radioactive decay 52 journal Geology 52 sedimentary rocks 52 geologic formation 52 geologically 52 supercontinent 52 Paleocene 52 planktonic 52 peridotite 52 igneous rock 52 intertidal 52 glacial melt 52 subduction zones 52 abundances 52 fossils 51 Antarctic ice 51 Antarctic ozone 51 ejecta 51 Chicxulub 51 polar caps 51 marine invertebrates 51 methane 51 volcanically active