CAJ | 학술논문

海洋沉积物中的硫酸盐-甲烷反应界面（SMI）的深度变化能够指示下伏甲烷水合物的赋存状态。本文通过对南海北部陆坡天然气水合物潜在分布区沉积物间隙水化学和自生碳酸盐氧、碳同位素组成资料系统分析和对比，探讨了南海北部陆坡沉积物的 SMI深度空间变化对下伏甲烷水合物的赋存状态的指示意义。结果表明，南海北部陆坡沉积物的 SMI的深度呈现出从西南-东北变浅的趋势，这一趋势与自生碳酸盐的碳同位素组成揭示的甲烷释放量增大趋势有很好的对应关系，进而表明在南海北部陆坡从西南-东北甲烷水合物的埋藏深度变浅或者甲烷水合物的分解程度增大。
해양침적물중적류산염-갑완반응계면（SMI）적심도변화능구지시하복갑완수합물적부존상태。본문통과대남해북부륙파천연기수합물잠재분포구침적물간극수화학화자생탄산염양、탄동위소조성자료계통분석화대비，탐토료남해북부륙파침적물적 SMI심도공간변화대하복갑완수합물적부존상태적지시의의。결과표명，남해북부륙파침적물적 SMI적심도정현출종서남-동북변천적추세，저일추세여자생탄산염적탄동위소조성게시적갑완석방량증대추세유흔호적대응관계，진이표명재남해북부륙파종서남-동북갑완수합물적매장심도변천혹자갑완수합물적분해정도증대。
The depth of sulfate-metnane interface (SMI) in sediments could indicate occurring status of methane hy-drate .By systimatically paralell analysis of pore water geochemical data and authgenic cabonate oxygen and carbon isotopic data available from the potential gas hydrate areas of the northern slope of the South China Sea (SCS) ,the implication of spatial variation of sulfate-metnane interface in sediments for occurring status of underlying methane hydrate in the northern slope of SCS was discussed .It was illustrated that the SMI in sediments of the northern slope of SCS tends to be shallow from the southwest to the northeast .The spatial variation of SMI exactly corre-sponds to accretion of released methane which was indicated by carbon isotope of the authigenic carbonate ,implica-ting that the buried depth of underlying methane hydrate temds to be shallow ,or decomposition of underlying methane hydrate temds to be intensive from the southwest to the northeast .