The westem slope of the Okinawa trough has been considered to experience important methane seep activities. Abundant terrigenous sediments supply and widely developed normal faults make this area an ideal place for me...The westem slope of the Okinawa trough has been considered to experience important methane seep activities. Abundant terrigenous sediments supply and widely developed normal faults make this area an ideal place for methane production, methane fluids migration and associated anaerobic oxidation of methane.展开更多
Objective Authigenic pyrite often develops extensively in marine sediments,which is an important product of sulfate reduction in an anoxic environment.It has a specific appearance and complicated sulfur isotopic prope...Objective Authigenic pyrite often develops extensively in marine sediments,which is an important product of sulfate reduction in an anoxic environment.It has a specific appearance and complicated sulfur isotopic properties,and acts as important evidence of methane seep in marine sediments.Strong AOM（anaerobic oxidation of methane）activity has developed in the Okinawa Trough.展开更多
Anaerobic oxidation of methane(AOM) is an important biogeochemical process, which has important scientific significance for global climate change and atmospheric evolution. This research examined the δ^(34)S, terrige...Anaerobic oxidation of methane(AOM) is an important biogeochemical process, which has important scientific significance for global climate change and atmospheric evolution. This research examined the δ^(34)S, terrigenous clastic indices of TiO_(2) and Al_(2)O_(3), and times for formation of the Ba front at site SH1, site SH3 and site 973-4 in the South China Sea. Three different coupling mechanisms of deposition rate and methane flux were discovered. The different coupling mechanisms had different effects on the role of AOM. At site 973-4, a high deposition rate caused a rapid vertical downward migration of the sulphate–methane transition zone(SMTZ), and the higher input resulted in mineral dissolution. At site SH3, the deposition rate and methane flux were basically in balance,so the SMTZ and paleo-SMTZ were the most stable of any site, and these were in a slow process of migration. At site SH1, the methane flux dominated the coupled mode, so the movement of the SMTZ at site SH1 was consistent with the general understanding. Understanding the factors influencing the SMTZ is important for understanding the early diagenesis process.展开更多
基金supported by the National Natural Science Foundation of China(grant No.41306062)the Key Laboratory of Gas Hydrate Foundation(grant No.SHW [2014]-DX-04)
文摘The westem slope of the Okinawa trough has been considered to experience important methane seep activities. Abundant terrigenous sediments supply and widely developed normal faults make this area an ideal place for methane production, methane fluids migration and associated anaerobic oxidation of methane.
基金supported by the National Natural Science Foundation of China (grants No.41306062 and 41474119)the Key Laboratory of Gas Hydrate Foundation (grant No.SHW[2014]-DX-04)
文摘Objective Authigenic pyrite often develops extensively in marine sediments,which is an important product of sulfate reduction in an anoxic environment.It has a specific appearance and complicated sulfur isotopic properties,and acts as important evidence of methane seep in marine sediments.Strong AOM（anaerobic oxidation of methane）activity has developed in the Okinawa Trough.
基金The Guangdong Basic and Applied Basic Research Fund Project under contract No.2021A1515011509the Municipal Science and Technology Program of Guangzhou under contract No.201904010311the Special Project for Marine Economy Development of Guangdong Province under contract No.GDME-2018D002。
文摘Anaerobic oxidation of methane(AOM) is an important biogeochemical process, which has important scientific significance for global climate change and atmospheric evolution. This research examined the δ^(34)S, terrigenous clastic indices of TiO_(2) and Al_(2)O_(3), and times for formation of the Ba front at site SH1, site SH3 and site 973-4 in the South China Sea. Three different coupling mechanisms of deposition rate and methane flux were discovered. The different coupling mechanisms had different effects on the role of AOM. At site 973-4, a high deposition rate caused a rapid vertical downward migration of the sulphate–methane transition zone(SMTZ), and the higher input resulted in mineral dissolution. At site SH3, the deposition rate and methane flux were basically in balance,so the SMTZ and paleo-SMTZ were the most stable of any site, and these were in a slow process of migration. At site SH1, the methane flux dominated the coupled mode, so the movement of the SMTZ at site SH1 was consistent with the general understanding. Understanding the factors influencing the SMTZ is important for understanding the early diagenesis process.
