针对深部咸水层CO2地质封存过程中流体的运移和压力的传递现象，利用美国Frio地区的CO2咸水层封存试验实测数据，建立二维多岩相结构模型，模拟分析CO2地质封存中CO2注入阶段岩石孔渗性能的变化特征、岩层压力增加的变化特征以及CO2羽流的演化规律。结果表明，超临界CO2在驱替咸水溶液的过程中形成类似漏斗状的扩散晕，蒸发作用产生的盐沉淀主要位于井附近的单气相区，随着盐沉淀的增加，井周围的渗透率降低、压力积聚；盖层渗透性提高避免了储层内部出现过大压力，但却增加了泄漏的可能性。%The process of CO2 sequestration in deep saline aquifers involves fluid migration and pressure transmission. Based on the field data of CO2 sequestration in saline aquifers in the Frio region of the United States, a two⁃dimensional multi⁃lithofacies model was established. The variation characteristics of the rock permeability during CO2 injection, the variation characteristics of the rock pressure, and the evolution of the CO2 plume were simulated and analyzed. The results show that the formation of a funnel⁃shaped diffusion halo was observed when supercritical CO2 displaced the salt water, and salt precipitation due to evapotranspiration mainly occurred in the single gas phase region near the well. As salt precipitation increased, the permeability near the well decreased and the pressure increased. If the permeability of the cap rock is improved, the pressure in the reservoir will decrease, but the possibility of leakage will increase.
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