Abstract:
The Yulin-Shenmu region, located in the northeastern Ordos Basin, boasts abundant carbon sources and a stable geological structure, making it an advantageous site for CO
2 sequestration in saline aquifers. This study focuses on the Zhi 3 Member of the Zhifang Formation and the Shiqianfeng Formation, conducting CO
2-water-rock interaction experiments and CO2 displacement tests to analyze the CO
2 injectivity potential of saline aquifers. The CO
2-water-rock interaction experiments reveal that upon CO
2 injection, silicate minerals such as clay minerals and feldspars undergo varying degrees of dissolution, accompanied by the precipitation of new minerals like calcite and halite. The CO
2 displacement tests indicate an increase in sandstone porosity after CO
2 injection, suggesting that the initial mineral dissolution effects outweigh those of mineral precipitation, effectively enhancing the injectivity of the reservoir. Based on CO
2 saturation calculations, the Shiqianfeng Formation exhibits good sequestration potential and is identified as the optimal target formation for subsequent CO
2 sequestration projects in saline aquifers.