Diagenesis and CaCO3 Dissolution in Sediments of the EasternEquatorial Atlantic Ocean and Continental Margin Off Cape Hatteras

小行星9617430 将在热带大西洋东部和北大西洋大陆隆起西部的海洋沉积物中测量碳酸钙的溶解。 研究区域具有扩展对CaCO 3溶解的理解的关键特征：（1）底层沃茨相对于方解石的饱和度范围，从CO 32-=28到=40，包括明显的欠饱和度-溶解模型中约束参数的理想条件-和过饱和度，这对于直接测量方解石溶跃层以上沉积物中的溶解速率是必不可少的;（2）重要的溶解控制Corg：降雨到海底的物质中的CaCO_3比例似乎相当高，在某些地区超过2.5mol/mol，与以前研究的其他上饱和层区相反;（3）该地区既包括高沉积物O2需求区（佛得角高原和北大西洋西部），大西洋边缘）和一个需求量较低，典型的非上升流远洋区（塞拉利昂海隆）;（4）塞拉利昂海隆一直是广泛的沉积学和古海洋学调查的地点，产生了大量的辅助数据，用于分析有机物氧化和CaCO 3溶解，并允许评价 饱和层以上溶解的沉积学指标;（5）研究区包括低至中等%CaCO3（W.N.）的高通量站点。大西洋边缘）和高%CaCO3（佛得角高原），允许评价这一因素，作为孔隙水和底栖室技术测量的溶解速率差异的解释。 考察海底各种条件下沉积物氧化和溶解过程的变异性，对于准确解释沉积记录和基于模型预测人为CO2的最终命运至关重要。

9617430 Martin Dissolution of CACO3 will be measured in marine sediments of the eastern tropical Atlantic Ocean and western north Atlantic continental rise. The study areas have key characteristics for extending understanding of CaCO3 dissolution: (1) the range in saturation of bottom waters with respect to calcite, from CO32-=28 to =40, includes both substantial undersaturation -- ideal for constraining parameters in dissolution models -- and supersaturation, which is essential for the direct measurement of dissolution rates in sediments above the calcite lysocline; (2) the values of the important, dissolution-controlling Corg : CACO3 ratio in the material raining to the sea floor appear to be quite high, in some areas exceeding 2.5 mol/mol, in contrast to other above- saturation horizon regions that have been studied previously; (3) the area includes both a regions of high sediment O2 demand (the Cape Verde Plateau and western N. Atlantic margin) and one of lower demand, typical of non-upwelling, pelagic areas ( the Sierra Leone Rise); (4) the Sierra Leone Rise has been the site of extensive sedimentological and paleoceanographic investigation, resulting in a substantial set of ancillary data for the analysis of organic matter oxidation and CaCO3 dissolution, and allowing evaluation of the sedimentological indicators to above-saturation horizon dissolution; and (5) the study areas include high flux sites with low to moderate %CaCO3 (W.N. Atlantic margin) and with high %CaCO3 (Cape Verde Plateau, allowing evaluation of this factor as an explanation for discrepancies in dissolution rates measured by pore water and benthic chamber techniques. The examination of the variability in sedimentary oxidation and dissolution processes over the range of conditions on the sea floor is essential to accurate interpretations of the sedimentary record and to model-based predictions of the ultimate fate of anthropogenic CO2.