The TMSA hypothesis: Do clay-mineral interlayer surfaces provide an unrecognized sink for organic carbon in the geological record?

本研究将验证一种假设，即有机碳在黏土矿物层间表面的吸附是地质记录中碳封存和保存的重要模式。该模型为有机碳埋藏和某些黑色页岩矿床的形成提供了统一的理论，其中存在于天然水体和孔隙流体中的溶解有机碳被碎屑粘土矿物的带电矿物表面所吸引，并通过物理遮蔽而不被微生物降解。埋藏后，矿物表面可能会协调复杂有机物质（如干酪根）的聚合，并在变质过程中催化裂解。拟议的研究将：1)确定一系列黑色页岩矿床、具有重要经济意义的烃源岩和现代沉积物中层间矿物表面积与总有机碳之间关系的地质范围；2)利用x射线衍射（XRD）技术和晶体边缘的高分辨率透射电子显微镜（HRTEM）成像，确定或排除这些矿床的蒙脱石层间部位存在有机物，并确定是否存在与矿物相关的无定形干酪根；3)测量与矿物表面相关的OM与使用密度和离心技术分离的总体积TOC和颗粒分数的组成差异。

This research will test the hypothesis that the adsorption of organic carbon onto the interlayer surfaces of smectitic clay minerals comprises a significant mode of carbon sequestration and preservation in the geologic record. This model provides a unifying theory for organic carbon burial and the formation of some black shale deposits in which dissolved organic carbon present in natural waters and pore fluids is attracted to charged mineral surfaces of detrital clay minerals, and preserved from microbial degradation by physical sheltering. Upon burial, mineral surfaces may act to coordinate polymerization of complex organic substances such as kerogen and catalyze cracking during catagenesis. The proposed research will: 1) determine the geological extent of the relationship between interlayer mineral surface area and total organic carbon in a range of black shale deposits, economically important source rocks, and modern sediments, 2) establish or dismiss the presence of organic matter within the smectite interlayer sites of these deposits using X-ray diffraction (XRD) techniques and high resolution transmission electron microscopy (HRTEM) imaging of crystal edges and determine whether there is amorphous kerogen that is mineral associated, and 3) measure the compositional differences of OM associated with mineral surfaces versus the total bulk TOC and particulate fraction separated using density and centrifugation techniques.