Stable isotopes, sedimentology and geochemical analyses of Middle Eocene to early Miocene sediments of ODP Site 177-1090

During Leg 177 of the Ocean Drilling Program (ODP), a well-preserved middle Eocene to lower Miocene sediment record was recovered at Site 1090 on the Agulhas Ridge in the Atlantic sector of the Southern Ocean. This new sediment record shows evidence of a hitherto unknown late Eocene opal pulse. Lithological variations, compositional data, mass-accumulation rates of biogenic and lithogenic sediment constituents, grain-size distributions, geochemistry, and clay mineralogy are used to gain insights into mid-Cenozoic environmental changes and to explore the circumstances of the late Eocene opal pulse in terms of reorganizations in ocean circulation. […]

在海洋钻探计划（ODP）的第177航次中，于南大洋大西洋区域的阿古拉斯脊1090号站位，成功提取了从中新世至下中新世的保存完好的沉积记录。这一新的沉积记录揭示了之前未知的晚中新世蛋白石脉冲的迹象。通过对岩石学变化、成分数据、生物成因和岩成因沉积组分的累积速率、粒度分布、地球化学和粘土矿物学的研究，我们得以深入洞察中新世中期环境变化，并从海洋环流重组的角度探讨晚中新世蛋白石脉冲发生的条件。