Deep CO₂ storage reservoirs show a wide range of heterogeneous structures across different scales. Here, we show how high-resolution heterogeneity in both permeability and capillary entry pressure control dissolution and local capillary trapping of supercritical CO₂ (ScCO₂). Prior works mainly considered homogeneous reservoirs or simplified heterogeneity with horizontal and fixed capillary transition zones. Most of those studies ignored simultaneous free-phase ScCO₂ spreading and solutal fingering. To advance understanding of heterogeneity effects, we have performed two-dimensional numerical simulations for ScCO₂ injection into the middle of a storage reservoir. We have computed metrics including the spatial plume moments to compare the dissolution trapping and spreading of ScCO₂ during the injection and post-injection period for different variances and correlation lengths of log-normal permeability and capillary entry pressure fields. The results show that the second-order spatial moment of the ScCO₂ saturation field in the horizontal direction decreases by 10% as the permeability variance increases from 0.1 to 3.0. But it decreases by 50% as the capillary entry pressure variance becomes 1.1. For higher capillary entry pressure variance, the ratio of dissolved CO₂ mass to free-phase ScCO₂ mass decreases, showing higher local capillary trapping. The vertical distance between the centers of mass of the ScCO₂ and dissolved CO₂ plumes (representing the downward flow of dissolved CO₂ through solutal fingering) is greater for heterogeneous reservoirs.

深层的CO ₂储集层在不同规模上显示出广泛的非均质结构。在这里，我们显示了渗透率和毛细管入口压力中的高分辨率异质性如何控制超临界CO ₂（ScCO ₂）的溶解和局部毛细管捕集。先前的工作主要考虑均质油藏或具有水平和固定毛细管过渡带的简化非均质性。这些研究大多数都忽略了同时的自由相ScCO ₂扩散和手指指法。为了进一步了解异质性效应，我们对ScCO ₂进行了二维数值模拟注入储层中部。我们已经计算了包括空间羽流矩在内的度量标准，以比较对数正态渗透率和毛细管进入压力场的不同方差和相关长度，在注入和注入后时间段内，ScCO ₂的溶出陷获和散布。结果表明，随着渗透率方差从0.1增大到3.0 ，ScCO ₂饱和场在水平方向上的二阶空间矩减小了10％。但是，随着毛细管入口压力方差变为1.1，它降低了50％。对于更高的毛细管入口压力变化，溶解的CO ₂质量与自由相ScCO ₂的比率质量下降，显示出更高的局部毛细管捕集。对于非均质储层，ScCO ₂质心和溶解的CO ₂羽流的质心之间的垂直距离（代表溶解的CO ₂通过稀疏指状流向下流动）更大。