Raised bogs are the key source of methane in West Siberia terrestrial seeps

The expansive plains of western Siberia contain globally significant carbon stocks, with the largest peatland complex in the world overlying the planet’s largest known hydrocarbon basin. Numerous terrestrial methane seeps have been recently discovered on this landscape, located along the Ob and Irtysh River floodplains in hotspots covering more than 2,500 km2. The origin of methane from these seeps is a matter of both practical and academic interest. The release of even negligible portions of western Siberia’s vast carbon pool will have global climate implications. We articulated three hypotheses to explain the origin and migration pathways of methane within these seeps: (H1) uplift of Cretaceous-aged methane from deep petroleum reservoirs along faults and fractures, (H2) release of Oligocene-aged methane capped or trapped by degrading permafrost, and (H3) horizontal migration of Holocene-aged methane from surrounding peatlands. We tested these hypotheses using a range of geochemical to..., , Files could be opened using simple \"office\" software. Data format is .xlsx. Column names are explained in README.txt,