Estimation of faults leakage potential is an essential component of CO₂ storage integrity analysis. The selection of deep saline aquifers for CO₂ storage in these settings mandates the modeling of fault-related fluid flow to estimate the most probable leakage rates. Faults usually have complex structures with heterogeneities and anisotropies over a range of scales because of which local capillary trapping becomes significantly important. We quantitatively investigate the implications of local capillary trapping for storage integrity and monitoring. Reservoir simulation results for a representative normal fault in a potential storage site in southern Louisiana with three possible damage zone configurations of homogenous, heterogeneous with fragmented core, and heterogeneous with intact core are presented. For each configuration, three cases are modeled to study the sensitivity of dissolution and local capillary trapping. Our results show that dissolution and local capillary trapping impede the upward migration of CO₂, and may reduce leaked volume by more than 19% in some of the cases. It is also noted that presence of high permeability connected streaks may lessen the positive contributions of dissolution and local capillary trapping in reducing CO₂ leakage. Moreover, capillary trapping significantly alters the pressure and saturation gradients locally and it may complicate monitoring strategies if extrapolation is required over larger length scales.

故障泄漏可能性的估计是CO ₂储存完整性分析的重要组成部分。CO ₂深层盐水层的选择这些设置中的存储要求对与故障相关的流体流进行建模，以估计最可能的泄漏率。断层通常具有在一定范围内具有异质性和各向异性的复杂结构，因此，局部毛细管捕集变得尤为重要。我们定量研究了局部毛细管捕集对存储完整性和监控的影响。给出了路易斯安那州南部潜在储层中具有代表性的正常断层的储层模拟结果，该储层具有三种可能的破坏带构造，即均质，不均质的碎裂岩心和不均质的完整岩心。对于每种配置，对三种情况进行建模，以研究溶出度和局部毛细管捕集的敏感性。₂，在某些情况下可能会使泄漏量减少19％以上。还应注意的是，高渗透性连接条纹的存在可能会减少溶解和局部毛细管捕集对减少CO ₂泄漏的积极贡献。此外，毛细管捕获会显着改变局部压力和饱和度梯度，如果需要在更大的长度范围内进行外推，可能会使监测策略复杂化。