We performed a numerical modeling study focused on the relationship between post-injection plume migration and leakage risks at geologic CO₂ storage sites. We use the model for Rock Springs Uplift in southwestern Wyoming as our hypothetical case study. We performed multiple sets of reservoir simulations, each with 29 equi-probable realizations of reservoir permeability heterogeneity, simulating different injection scenarios. Three different CO₂ injection rates and an open and compartmentalized reservoir are evaluated. We applied newly developed moment-based plume mobility metrics to characterize migration and evolution of injected CO₂ plume. We applied the integrated assessment model developed by the National Risk Assessment Partnership (NRAP-IAM-CS) using the results of reservoir simulations of CO₂ and overpressure to quantify potential CO₂ and brine leakage through wells and resulting groundwater aquifer impacts. The plume mobility metrics provide detailed analyses of the effect of reservoir permeability heterogeneity, CO₂ injection rate, and compartmentalization on CO₂ plume and overpressure areas, velocities, and spreading. Based on leakage risk assessment our results indicate that lack of injected CO₂ plume stability (or non-zero plume mobility) may not directly imply groundwater aquifer endangerment and the leakage risks are dependent on multiple factors beyond CO₂ plume stability including presence of wells and their locations and types.

我们进行了数值建模研究，重点研究了注入后羽流迁移与地质CO ₂储存地点泄漏风险之间的关系。我们将怀俄明州西南部的岩泉抬升模型用作假设案例研究。我们进行了多组油藏模拟，每组都有29个等概率的油藏渗透率非均质性实现，模拟了不同的注入情景。评估了三种不同的CO ₂注入速率以及一个开放的分隔储层。我们应用了新开发的基于矩的羽流迁移率指标来表征注入的CO _2的迁移和演化羽。我们使用由国家风险评估合作伙伴关系（NRAP-IAM-CS）开发的综合评估模型，利用CO ₂和超压的油藏模拟结果量化了潜在的CO ₂和盐水通过井的渗漏以及对地下水含水层的影响。羽状流度指标提供了储层渗透率非均质性，CO ₂注入速率和分隔对CO ₂羽状流和超压面积，速度和扩散的影响的详细分析。根据泄漏风险评估，我们的结果表明缺少注入的CO ₂羽状流稳定性（或非零羽状流淌性）可能并不直接暗示地下水蓄水层的危害，泄漏风险取决于除CO ₂羽状流稳定性以外的多种因素，包括井的存在及其位置和类型。