Related by context. Frequent words. (Click for all words.) 71 isotope ratios 66 isotopic composition 62 isotopic 60 zircons 60 marine sediments 60 abundances 60 oxygen isotopes 59 Archaean 59 elemental composition 59 radiocarbon 57 lithosphere 57 magmas 57 lavas 57 aragonite 57 lake sediments 56 otolith 56 radioactive decay 56 Cenozoic 56 osmium 56 biogeochemical 56 hydrologic cycle 55 olivine 55 igneous rocks 55 Quaternary 55 monazite 55 basaltic 54 solar nebula 54 noble gases 54 oceanic crust 54 microfossils 54 igneous 54 electron density 54 apatite 54 metamorphic rocks 53 foraminifera 53 depositional 53 faunal 53 earth crust 53 continental crust 53 mineralogy 53 basalts 52 otoliths 52 protoplanetary disk 52 sorption 52 sediments 52 igneous rock 52 clathrates 52 labile 52 fluxes 51 magmatic 51 Carboniferous 51 chemical composition 51 crustal 51 deglaciation 51 calcareous 51 morphology 51 interglacial 51 atmospheric CO 51 lunar soil 51 terrestrial ecosystems 51 morphologies 51 abiotic 50 atmospheric methane 50 adsorbed 50 perovskite 50 methanogens 50 spherules 50 meteorite impacts 50 moraines 50 diatom 50 stromatolites 50 Precambrian 50 geologic 50 interglacial period 50 surficial 50 anisotropy 49 ALH# 49 relict 49 regolith 49 silicate 49 radiocarbon dated 49 Supplementary Fig 49 Mitochondrial DNA 49 geomorphology 49 placental mammals 49 sodium potassium 49 Fig. 1A 49 carbonate rocks 49 facies 49 supergene 49 heavily cratered 49 arsenate 49 planetesimals 49 morphologically 49 Meridiani 49 gravity anomalies 49 metastable 49 stable isotope 49 lithology 49 sedimentary rock 49 clasts