New Mexico Institute of Mining and Technology, 801 Leroy Place, Socorro, NM, 87801, USA.
Petroleum Recovery Research Center, 801 Leroy Place, Socorro, NM, 87801, USA.
Sci Rep. 2022 Jul 29;12(1):13023. doi: 10.1038/s41598-022-16990-x.
This study evaluates the chemo-mechanical influence of injected CO on the Morrow B sandstone reservoir and the upper Morrow shale caprock utilizing data from the inverted 5-spot pattern centered on Well 13-10A within the Farnsworth unit (FWU). This study also seeks to evaluate the integrity of the caprock and the long-term CO storage capability of the FWU. The inverted 5-spot pattern was extracted from the field-scale model and tuned with the available field observed data before the modeling work. Two coupled numerical simulation models were utilized to continue the study. First, a coupled hydro-geochemical model was constructed to simulate the dissolution and precipitation of formation minerals by modeling three intra-aqueous and six mineral reactions. In addition, a coupled hydro-geomechanical model was constructed and employed to study the effects of stress changes on the caprock's porosity, permeability, and ground displacement. The Mohr-Coulomb circle and failure envelope were used to determine caprock failure. In this work, the CO-WAG injection is followed by the historical field-observed strategy. During the forecasting period, a Water Alternating Gas (WAG) injection ratio of 1:3 was utilized with a baseline bottom-hole pressure constraint of 5500 psi for 20 years. A post-injection period of 1000 years was simulated to monitor the CO plume and its effects on the CO storage reservoir and caprock integrity. The simulation results indicated that the impacts of the geochemical reactions on the porosity of the caprock were insignificant as it experienced a decrease of about 0.0003% at the end of the 1000-year post-injection monitoring. On the other hand, the maximum stress-induced porosity change was about a 1.4% increase, resulting in about 4% in permeability change. It was estimated that about 3.3% of the sequestered CO in the formation interacted with the caprock. Despite these petrophysical property alterations and CO interactions in the caprock, the caprock still maintained its elastic properties and was determined to be far from its failure.
本研究利用位于 Farnsworth 单元（FWU）内的 13-10A 井的五点反演井位数据，评估注入 CO 对 Morrow B 砂岩储层和上部 Morrow 页岩盖层的化学机械影响。本研究还旨在评估盖层的完整性和 FWU 的 CO 长期封存能力。五点反演井位是从现场尺度模型中提取出来的，并在建模工作之前，利用可用的现场观测数据进行了调整。利用两个耦合数值模拟模型继续进行研究。首先，构建了一个耦合水-地球化学模型，通过模拟三个水相和六个矿物反应来模拟地层矿物的溶解和沉淀。此外，还构建并采用了一个耦合水-地球力学模型，研究了应力变化对盖层孔隙度、渗透率和地面位移的影响。莫尔-库仑圆和破坏包络线用于确定盖层破坏。在这项工作中，CO-WAG 注入遵循历史上的现场观测策略。在预测期内，采用了 1:3 的水交替气（WAG）注入比，同时在 20 年内保持 5500 psi 的井底压力基线约束。模拟了 1000 年的注入后监测期，以监测 CO 羽流及其对 CO 储存储层和盖层完整性的影响。模拟结果表明，由于在 1000 年注入后监测期末，盖层的孔隙度减少了约 0.0003%，因此地球化学反应对盖层孔隙度的影响并不显著。另一方面，最大的应力诱导孔隙度变化约为 1.4%的增加，导致渗透率变化约为 4%。据估计，大约 3.3%的注入地层中的封存 CO 与盖层相互作用。尽管盖层的这些岩石物理性质发生了变化和 CO 的相互作用，但盖层仍保持其弹性性质，远未达到破坏状态。
