Related by context. Frequent words. (Click for all words.) 69 geologic formations 64 geological formations 62 CO2 sequestration 62 salt domes 58 salt caverns 58 methane hydrate 58 underground caverns 58 coal seams 58 methane hydrates 57 injection wells 57 shales 56 hydrocarbons 56 kerogen 56 carbon dioxide sequestration 56 aquifers 56 evaporation ponds 56 methane 55 gasfields 55 Arctic permafrost 55 seabeds 54 economically recoverable 54 gas hydrates 54 magma chamber 53 geologically 53 geologic formation 53 sedimentary rock 53 subsurface 53 sedimentary basins 53 alluvial deposits 53 Gippsland Basin 53 geosequestration 53 marine sediments 53 caverns 53 microfossils 53 peat bogs 53 Coal seam 52 frac sand 52 CO -2 52 reservoirs 52 shale deposits 52 gasified 52 shale formations 52 hydrothermal vent 52 depositional 52 geothermal 52 minable 52 carbon dioxide 51 permafrost 51 storage caverns 51 sediments 51 biogenic 51 basins 51 carbon sequestration 51 coalbed methane CBM 51 sequestration 51 lignite coal 51 underground aquifers 51 tailing ponds 51 CO2 51 sedimentary basin 51 carbon dioxide CO2 51 lignite 50 Surat Basin 50 Ghawar 50 peridotite 50 wellbores 50 shale 50 basalts 50 reinjection 50 coal seam 50 coalbed methane 50 overlie 50 Galilee Basin 50 porphyry deposit 50 lavas 50 carbonate rocks 50 Alberta tar sands 49 tailings 49 sandstone reservoirs 49 hydrocarbon 49 Georgina Basin 49 carbon capture 49 reservoir 49 technically recoverable 49 underground coal gasification 49 abiotic 49 contaminate groundwater 49 desalinate 48 Alaska Cook Inlet 48 CH4 48 contaminating groundwater 48 Lower Cretaceous 48 coal 48 condensates 48 hydrothermal activity 48 limestone caves 48 mineable 48 iron fertilization 48 coal seam methane 48 zeolites 48 aquifer