Clumped isotope constraints on the origins of reservoir methane from the Barents Sea

The Barents Sea basin is an oil and gas province containing more than 760 million tons of equivalents. reservoir geology the complex due to multiple episodes subsidence, uplift erosion, which opened a network extensional wrench related faults allowing for fluid migration. multifaceted geological history complicates efforts describe source characteristics natural in subsurface Sea. Here we apply stable isotopes, including methane clumped isotope measurements, thirteen gases from five (Skrugard Appraisal, Havis, Alta, Filicudi, Svanefjell) reservoirs Loppa High area southwestern estimate origins methane. We compare estimates formation temperature based on isotopes thermal evolution models region. find that has diverse microbial thermogenic sources forming equilibrating at temperatures ranging 34-238 °C. Our are consistent with area. These can be explained by generation expulsion window followed isotopic re-equilibration some methanogenesis and/or anaerobic oxidation Gases Skrugard Havis Alta have equilibration maximum burial temperatures, while Svanefjell current temperature, suggesting shallow reservoir. Filicudi other hand over points its history.