European carbonate margins as recorders of past global change: Cretaceous `greenhouse` versus Carboniferous `coldhouse` examples

化石大陆-海洋边界代表了区域和全球变化的独特档案。化石碳酸盐边缘记录了气候、排水模式、沉积物产生和迁移、古海面温度和海水地球化学的变化。我们提出了一个深入的研究和比较两个选定的利润率（北方西班牙和希腊），这代表了显着不同的情节地球历史的全球气候，大气pCO 2，海水成分和碳酸盐生产生物群。中石炭纪边缘（西班牙）代表了一个“冷室”的例子，晚白垩世边缘（希腊）提供了地球系统的“温室”模式的例子。首先，我们打算集中在两个边缘的沉积和层序地层格架。一个特别的重点将是对碳酸盐生产潜力的定量测定，以及无机与生物诱导和生物控制生产的作用。沉积学研究将半定量重建中石炭世和晚白垩世海平面变化。跨台地-盆地断面的同时期剖面可以确定相对海平面波动的幅度。与晚白垩世相比，预计这些在中石炭纪是不同的，当时冰川作用是重要的。其次，我们将适用于d13 C，d18 O，Sr同位素和微量元素的比例，以不同的碳酸盐材料，以揭示空间和时间的变化，海面温度，特别是古温跃层记录在地球化学的化石碳酸盐边缘在西班牙。化学地层学（d13 C，87 Sr/86 Sr）对上白垩统碳酸盐岩边缘对比具有重要意义。本研究的一个特别新颖的方面将是测试和应用钙同位素（d44 Ca）的沉积地球化学的石炭纪和白垩纪碳酸盐岩以及限制沉积环境。这些结果将与现代热带碳酸盐岩的岩心物质进行比较，以期获得外源钙循环的新见解。

Fossil continent - ocean boundaries represent unique archives of regional and global change. Changes in climate, drainage patterns, sediment production and transport, palaeo-sea surface temperatures and seawater geochemistry are recorded in fossil carbonate margins. We propose an in-depth study and comparison of two selected margins (Northern Spain and Greece), which represent significantly different episodes of Earth history in terms of global climate, atmospheric pCO2, seawater composition and carbonate producing biota. The mid-Carboniferous margin (Spain) represents a "coldhouse" example and the Late Cretaceous margin (Greece) provides an example of the "greenhouse" mode of Earth´s system. Firstly, we intend to concentrate on the sedimentologic and sequence stratigraphic framework of both margins. A special focus will be on the quantitative determination of the carbonate production potential, and the role of inorganic versus biologically induced and biologically controlled production. Sedimentological studies will lead to a semi-quantitative reconstruction of middle Carboniferous and Late Cretaceous sea-level changes. Coeval sections across platform-to-basin transects allow for a determination of amplitudes of relative sea-level fluctuations. Compared to the Late Cretaceous these are expected to be different during the middle Carboniferous when glacial eustasy was important. Secondly, we will apply d13C, d18O, Sr-isotopes and trace element ratios to different carbonate materials in order to reveal spatial and temporal variability of sea-surface temperatures and specifically of the palaeo-thermocline recorded in the geochemistry of fossil carbonate margins in Spain. Chemostratigraphy (d13C, 87Sr/86Sr) will be important for the correlation of Upper Cretaceous carbonate margins. A particular novel aspect of this study will be the testing and application of Ca isotopes (d44Ca) to the sedimentary geochemistry of Carboniferous and Cretaceous carbonates from well constrained depositional settings. These results will be compared to core material from modern tropical carbonates with the expectation to gain new insight in the exogenic calcium cycle.