Geologic formations provide potentially some of the largest volume capacities for CO₂ storage or sequestration. Potential storage sites can be deep saline aquifers, depleted oil reservoirs, and coal seams, surrounded by sealing layers to prevent CO₂ from leaking. It is therefore critical to understand mechanisms contributing to CO₂ trapping and CO₂ leaks. Both phenomena are governed by reactions at the interfaces of the reservoir and cap-rocks and are controlled by the complex chemistry and pore structures of rocks. Mechanisms at the macroscale are affected by the processes occurring at the nanoscale. This review highlights the necessity of multitechnique, multiscale characterization of rocks and points to the importance of surface analysis and surface science studies. Two shale rocks (seals) from Niobrara and Agardhfjellet formations with complex surface chemistry are used as examples throughout the paper. Typically, evaluation of rocks with x-ray diffraction, thermogravimetric analysis, Rock-Eval pyrolysis, gas adsorption, and electron microscopy combined with energy dispersive x-ray spectroscopy is conducted to provide valuable information about the bulk mineralogy, elemental composition, pore volume, and adsorbed species on the sample surface. These studies are necessary prior to designing surface sensitive experiments with x-ray photoelectron spectroscopy (XPS), guiding both sample preparation and sample analysis. XPS has been widely used to study the surface composition of rocks during the investigations of their fine-scale wettability, and the main findings are highlighted here. This paper also reviews the existing literature on ambient-pressure XPS, which provides new opportunities to study in situ chemical alteration due to interactions with CO₂ and offers recommendations for adapting this technique to study rock-fluid interactions, allowing for the identification of fundamental interactions during CO₂ sequestration and guide selection of formation sites for improved storage.

中文翻译：

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储层和盖层的表面和整体特征：过去，现在和将来

地质地层可能为CO _2的储存或封存提供了一些最大的容量。潜在的存储地点可能是深层盐水，储油层耗尽和煤层，并用密封层围起来以防止CO ₂泄漏。因此，了解导致CO ₂捕集和CO ₂捕集的机制至关重要泄漏。两种现象都受储层与盖层岩石界面反应的支配，并受岩石复杂的化学性质和孔隙结构控制。宏观上的机制受纳米级发生的过程影响。这篇评论突出了对岩石进行多技术，多尺度表征的必要性，并指出了表面分析和表面科学研究的重要性。本文以Niobrara和Agardhfjellet地层的两个页岩岩石（印章）为例，这些化学性质复杂。通常，通过X射线衍射，热重分析，Rock-Eval热解，气体吸附和电子显微镜结合能量色散X射线光谱学对岩石进行评估，以提供有关整体矿物学，元素组成，孔体积和样品表面上的吸附物质。在设计使用X射线光电子能谱（XPS）的表面敏感实验之前，必须进行这些研究，以指导样品制备和样品分析。XPS已广泛用于研究岩石的细级润湿性，并在此重点介绍了主要发现。本文还回顾了有关环境压力XPS的现有文献，这为研究提供了新的机会 XPS已被广泛用于研究岩石的细级润湿性，并在此重点介绍了主要发现。本文还回顾了有关环境压力XPS的现有文献，这为研究提供了新的机会 XPS已广泛用于研究岩石的细级润湿性，并在此重点介绍了主要发现。本文还回顾了有关环境压力XPS的现有文献，这为研究提供了新的机会由于与CO _2的相互作用而发生的化学原位变化，并提供了建议，使该技术适用于研究岩石-流体的相互作用，从而能够确定CO ₂封存过程中的基本相互作用，并指导选择形成部位以改善储存。