Stable isotopes of carbon and oxygen variations in foraminiferal shells have been widely used in paleo-environment studies. However, studies about the shells of benthic foraminifera in methane-hydrate-bearing sediments as reliable geochemical proxies to reconstruct the potential methane release events in the geologic past are rare. In this study, we present the stable carbon and oxygen isotopes of fossil benthic foraminifera including one epifaunal species (Cibicidoides wuellerstorfi) and two infaunal species (Bulimina mexicana and Uvigerina peregrina) from the Site U1447 of IODP 353 Expedition to trace methane events in the Andaman Sea, where one of the thickest and deepest gas hydrate stability zones was discovered. Theδ13C values of benthic foraminifera show that there are eight distinct inter-vals with negative values in the last～10 Myr, interpreted as a record of long-term fluctuations in meth-ane emission. Six of these methane events occurred during the glacial sea-level lowstands in the last～1.1 Myr. We, therefore, infer that the trigger mechanism for these events might be the hydrate destabi-lization caused by sea level fall. The methane events that occurred at～2.11 and～5.93 Ma are more like-ly related to the sudden changes in sedimentation, either slide events or marked variations in sedimen-tation rate.

Yue Cen;Jiasheng Wang;Xuan Ding;Dorrik Stow;Zhou Wang;Can Chen;Xiaochen Ma

Hubei Key Laboratory of Marine Geological Resources,College of Marine Science and Technology,State Key Laboratory of Biogeology and Environmental Geology,China University of Geosciences,Wuhan 430074,China;School of the Marine Sciences,China University of Geosciences,Beijing 100083,China;Institute of Geo-Energy Engineering,Heriot-Watt University,Edinburgh EH144AS,UK;State Key Laboratory of Marine Geology,Tongji University,Shanghai 200092,China

地球科学学刊（英文版）

[1]Yue Cen;Jiasheng Wang;Xuan Ding;Dorrik Stow;Zhou Wang;Can Chen;Xiaochen Ma-.Tracing the Methane Events by Stable Carbon Isotopes of Benthic Foraminifera at Glacial Periods in the Andaman Sea)[J].地球科学学刊（英文版）,2022(06):1571-1582

Foraminifera,epifaunal,Cibicidoides,wuellerstorfi,infaunal,Bulimina,Uvigerina,peregrina,U1447,vals,lowstands,destabi

Tracing,Methane,Events,by,Stable,Carbon,Isotopes,Benthic,Glacial,Periods,Andaman,Sea,isotopes,carbon,oxygen,variations,foraminiferal,shells,have,been,widely,paleo,environment,studies,However,about,benthic,methane,hydrate,bearing,sediments,reliable,geochemical,proxies,reconstruct,potential,release,events,geologic,past,rare,In,this,study,present,stable,fossil,including,species,two,mexicana,from,Site,IODP,Expedition,trace,where,thickest,deepest,gas,stability,zones,was,discovered,13C,values,show,that,eight,distinct,negative,last,Myr,interpreted,record,long,term,fluctuations,emission,Six,these,occurred,during,glacial,sea,level,We,therefore,infer,trigger,mechanism,might,lization,caused,fall,Ma,more,like,related,sudden,changes,sedimentation,either,slide,marked

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