2005-01-012024-05-17https://scholars.lib.ntu.edu.tw/handle/123456789/671566摘要：本研究已大致建立台灣西南海域Active margin硫酸鹽還原與甲烷之相關性，94年度將研究調查台灣西南海域passive margin之硫酸鹽還原與甲烷之關係。台灣西南海域active margin硫酸鹽還原與甲烷高區有非常顯著之相關性，高甲烷區有快速硫酸鹽還原，反之，沒有甲烷或低甲烷濃度地區之硫酸鹽還原速率則依循水深有定比關係。台灣西南海域Active margin鄰近台灣有大量的陸源物質沉降於此，大量的沉降通量加速此區域之硫酸鹽還原與甲烷之生成。而Passive margin雖無大量陸源物質輸送至此區域，然而此區域之湧升流亦可能造成基礎生產力的增加導致海源有機碳的沉降，而導致快速硫酸鹽還原及甲烷的生成。Passive margin 與Active margin環境下, 甲烷的生成及保存應有差異，然目前對此並無足夠研究，究竟硫酸鹽與甲烷的生成與Active margin之差異為何，何者適宜甲烷之生成與保存，目前之研究均無法充分之解釋。 本年度之研究乃針對Passive margin之硫酸鹽還原與甲烷之生成加以探討，期望能尋找了解甲烷水合物在何種環境下有最佳的生成與保存。研究調查<br> Abstract: Sulfate reduction and methane formation are two closely link geochemical processes occurring sequentially in marine sediments. This research intends to use this relationship in investigating sulfate reduction, hydrate formation and related diagenetic processes in continental margin sediments southwest of Taiwan in order to exploit the potential use of using sulfate reduction as a proxy for gas hydrate exploration. A positive correlation was established in the active margin sediments based on previous year’s data. In active margin sediments, faster sulfate reduction occurred in regions with higher methane contents while slower sulfate reduction occurred in sediments with lower or no methane. This proposal intend to study sulfate reduction and its relationship with gas hydrate in the passive margin sediments southwest of Taiwan. We intend to understand the degree of sulfate reduction variation in the passive margin sediments, its relationships with methane migration, the differences between active and passive margin and the mechanisms controlling the variations. This research will conduct a detail sampling plan and a reconnaissance survey. We will use OR-1 piston core, both short piston and long piston, for detail study and OR-1 and II for reconnaissance survey using gravity core. Our analytical works include pore water sulfate, sulfide, chloride, and sediment AVS, pyrite-S, organic carbon, carbonate carbon, water content. The result should help to establish basic information for gas hydrate and sulfate reduction in the study environments.甲烷硫酸鹽passive margin有機碳methanesulfatepassive marginorganic carbon