Optimal Selection of Favorable Areas for CO2 Geological Storage in the Majiagou Formation in the Ordos Basin

<p>CO<sub>2</sub> geological storage (CGS) technology is currently one of the best choices for large-scale low-cost CO<sub>2</sub> emission reduction in the world, and the primary issue of CO<sub>2</sub> geological storage is the optimization of the selection of favorable areas for CO<sub>2</sub> storage. In view of the insufficient research on the optimization of favorable areas for CO<sub>2</sub> geological storage in the Majiagou Formation in the Ordos Basin, this study aims to determine the boundaries of the CO<sub>2</sub> geological storage area in the Ordos Basin by studying the temperature and pressure conditions, reservoir conditions, structural conditions, caprock conditions , and the salinity conditions of the formation water using a large amount of geological, drilling, geophysical and experimental laboratory data. After the regional boundary of the CO<sub>2</sub> geological sequestration is determined, it can be optimized and CO<sub>2</sub> geological sequestration can be conducted in the areas that have favorable reservoir conditions, are relatively close to CO<sub>2</sub> emission sources, have a high degree of exploration, have an appropriate formation depth and have a small impact on the development of other mineral resources. The results show that (1) the areas suitable for the geological storage of CO<sub>2</sub> in the Ordos Basin are located in the distribution area of the Majiagou Formation in the Tianhuan Depression, except for the missing areas in the central paleo-uplift. The ares to the east of the Baiyanjing-Shajingzi fault, to the north of the northern margin of the Weibei uplift, to the west of the Yellow River fault, and to the south of the Yimeng uplift are suitable for CO<sub>2</sub> geological storage. (2) Based on the three aspects of technology, safety, and economic feasibility, it was determined that the Wushenqi-Jingbian-Yan'an karst slope area (I<sub>1</sub>) is the best CO<sub>2</sub> geological storage area, and the Yulin-Mizhi karst basin area (I<sub>2</sub>) is a favorable area for the geological storage of CO<sub>2</sub> in the Ordos Basin.</p><p> </p>