Related by context. Frequent words. (Click for all words.) 58 snail shells 57 Fossilized 56 igneous rocks 56 seashells 56 salt crystals 56 stromatolites 55 microfossils 55 aragonite 55 lake sediments 55 middens 55 mussel shells 55 stalagmites 55 ammonites 55 sedimentary rock 55 radiocarbon dated 54 foraminifera 54 marine sediments 54 calcareous 54 carnelian 53 agates 53 Radiocarbon dating 53 isotope ratios 53 sediment cores 53 fossils 53 trilobites 53 bathymetric 53 lunar soil 52 zircons 52 fossil specimens 52 fossilized 52 lava tubes 52 elemental composition 52 undersea volcanoes 52 isotopic composition 51 Early Cretaceous 51 preserved fossils 51 Martian rocks 51 underwater volcanoes 51 pottery shards 51 hydrothermal vent 51 igneous rock 51 moraines 51 mosaic floors 51 prehistoric 51 volcanic rock 50 flint tools 50 marine invertebrates 50 nanosized 50 stalagmite 50 rocks 50 calcite 50 dinosaur fossils 50 amethysts 50 amphorae 50 bathymetry 50 limestone caves 50 tidal pools 50 cenotes 49 petrified wood 49 abundances 49 coral formations 49 spherules 49 intertidal 49 striations 49 geodes 49 sediments 49 hieroglyphs 49 stalactite 49 Palaeolithic 49 chert 48 relict 48 Sediments 48 whalebone 48 fossilized remains 48 quartz crystals 48 quartz sand 48 Ancient Roman 48 dinosaur footprints 48 arrowheads 48 fragments 48 cinnabar 48 isotopic 48 excavated 48 Carrara marble 48 Pre Columbian 48 apatite 48 lacework 48 oceanic crust 48 papyri 48 amphipods 48 landforms 48 Fossils 48 garnets 48 patinas 48 ancient mariners 48 chalky white 48 red ocher 47 radiocarbon dating 47 stalactites 47 coprolites 47 coral