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墨西哥湾北部大陆坡下部深水区Alaminos Canyon冷泉碳酸盐岩结壳含有以双壳类和有孔虫为主的生物碎片,孔洞发育且常被针状文石充填.XRD分析显示结壳主要由文石组成(达98%).结壳中发育团粒、凝块和葡萄状文石等与渗漏系统微生物活动有关的沉积组构.结壳中生物碎屑的δ13C值为-4.9‰~-0.6‰,碳源主要来自海水.泥晶和亮晶文石的δ13C值为-31.3‰~-23.4‰,碳源主要来自生物降解的石油.对冷泉碳酸盐岩中生物壳体的14C测定表明冷泉活动至少持续了约10ka.碳酸盐岩结壳的酸可溶部分稀土元素总量很低(0.75~12.73μg/g),稀土元素页岩标准化配分模式具有明显的Ce负异常,表明结壳形成于氧化环境.
Deepwater in the lower continental slope of the northern Gulf of Mexico Alaminos Canyon Cold Spring Carbonate crusts contain biochar mainly dominated by bivalves and foraminifera, and are often filled with acicular aragonite. XRD analysis shows that crusts consist mainly of The composition of aragonite (up to 98%) is related to sedimentary structures such as aggregates, clots and grape-like aragonites in the crust, and the δ13C value of bioclastic in the crust is -4.9 ‰ ~ 0.6 ‰, and the carbon source is mainly from seawater.The δ13C values of clay and brilliant aragonite are from -31.3 ‰ to -23.4 ‰, and the source of carbon is mainly from biodegraded petroleum.The determination of 14C in biological shells in cold spring carbonate shows The activity of the cold spring lasted for at least about 10ka. The total amount of rare earth elements in the acid soluble fraction of carbonate crusts was very low (0.75-12.73μg / g), and the normalized RE pattern of REE shale had obvious negative Ce anomalies, The shell is formed in an oxidizing environment.