• 责任者：Bian Youyan (Key Laboratory of Marginal Sea Geology ; Guangzhou Institute of Geochemistry ; Chinese Academy of Sciences ; Guangzhou 510640 ; China) ; Chen Duofu
• 刊名：Geochimica
• 出版年：2013
• 卷期：42(3)
• 关键词：碳酸盐岩 ; carbonate rocks ; 岩石地球化学 ; lithogeochemistry ; 墨西哥 ; Mexico
• 页码：p.212-220
• 图表：illus., 2 tables, 49 refs.
• 分类号：0600
• issnNo：ISSN0379-1726
• isbnNo：CN44-1398/P

Seep carbonates collected from Green Canyon block 140, Gulf of Mexico, could be divided into three types： nodule-rich carbonates, bioclast-rich carbonates and massive carbonates. XRD investigation shows that high Mg-calcite and aragonite are the dominate minerals. Additionally, nodule-rich carbonates contain minor amounts of dolomite and bioclast-rich carbonates include some low Mg-calcite. Peloids, clotted microfabric and pyrite framboids are developed in carbonates and suggest a genesis linked with bacterial activities. The carbonates exhibit a large variation in ^δ13 values （-36.1‰ to 5.1‰）, suggesting multiple carbon sources that include thermogenic methane, seawater and residual CO2 from methanogenesis. Shells cemented in nodule-rich carbonates show ^14C ages between 46.5 ka and 25.8 ka BR bioclast-rich carbonates formed from 17.6 ka to 11.7 ka BE and massive carbonates have ^14C ages of 1.2 ka BR suggesting that seep activity was discontinuous.