Abstract The advection of seawater into the sediments deposited on the margins of Great Bahama Bank has been demonstrated to play in important role in ventilating the uppermost sediments, as well as supplying elements for diagenetic reactions deeper within the platform. Here, we implement a numerical model to calculate the rate of fluid advection at ODP Site 1003, using calcium isotopes as a tracer for fluid advection. A key parameter for this model, the rate of recrystallization of sediments, was constrained using the clumped isotope proxy. The model was tuned to existing datasets of clumped and carbonate calcium isotope measurements for this site. Results of this modeling effort indicate that, prior to ∼15 Ma, fluids were advected into the platform at a rate substantially lower than the present day. The rate of advection abruptly increased ∼13 Ma to a value greater than the present day. The increase in advective flux during the mid-Miocene coincides with a major reorganization of the platform from a ramp-like geometry to a steeper carbonate platform, indicating a change in the relative contributions of different mechanisms governing fluid flow on the platform margin and interior. This paper aims to explore the utility of using clumped and calcium isotopes to quantitatively reconstruct past fluid advection rates using this novel technique.

中文翻译：

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中中新世流体流入背风边缘大巴哈马银行的突然增加，受到 δ44Ca 和 Δ47 值的限制

摘要 海水平流进入沉积在大巴哈马海岸边缘的沉积物已被证明在为最上层沉积物通风以及为平台内更深处的成岩反应提供元素方面发挥着重要作用。在这里，我们实施了一个数值模型来计算 ODP 站点 1003 处的流体平流速率，使用钙同位素作为流体平流的示踪剂。该模型的一个关键参数是沉积物的再结晶速率，它使用成簇同位素代理进行约束。该模型已调整到该站点现有的聚集和碳酸盐钙同位素测量数据集。这种建模工作的结果表明，在~15 Ma 之前，流体以比现在低得多的速率平流进入平台。平流率突然增加~13 Ma 到比现在更大的值。中中新世期间平流通量的增加与平台从斜坡状几何形状到更陡峭的碳酸盐平台的重大重组相吻合，表明控制平台边缘和内部流体流动的不同机制的相对贡献发生了变化。本文旨在探索使用团块和钙同位素使用这种新技术定量重建过去的流体平流率的效用。表明控制平台边缘和内部流体流动的不同机制的相对贡献发生了变化。本文旨在探索使用团块和钙同位素使用这种新技术定量重建过去的流体平流率的效用。表明控制平台边缘和内部流体流动的不同机制的相对贡献发生了变化。本文旨在探索使用团块和钙同位素使用这种新技术定量重建过去的流体平流率的效用。