Correlation Between Poroelastic Stress Perturbation and Multidisposal Wells Induced Earthquake Sequence in Cushing, Oklahoma
Correlation Between Poroelastic Stress Perturbation and Multidisposal Wells Induced Earthquake Sequence in Cushing, Oklahoma
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俄克拉荷马州库欣多孔弹性应力扰动与多处置井诱发地震序列之间的相关性
DOI：
10.1029/2020gl089366
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发表时间：
2020-10-28
影响因子：
5.2
通讯作者：
Chen, Xiaowei
中科院分区：
文献类型：
--
作者：
Deng, Kai;Liu, Yajing;Chen, Xiaowei
2015年9月至2016年11月期间，在俄克拉荷马州的库欣镇附近检测到了100多次小型至中型地震，包括一次Mw 5.0级地震。地震序列与4 km范围内的4口污水处理威尔斯井具有时空联系。计算了多口威尔斯井注液引起的孔隙压力和应力扰动，并在库仑破裂应力框架下分析了地震危险性。尽管比孔隙压力扰动小一个数量级以上，剪切应力变化的符号，在假定的右旋断层运动的意义上，决定了地震的诱发。大多数重新定位的地震位于正剪应力变化区。我们的研究结果表明，孔隙弹性应力的变化也发挥了重要作用，在废水处理环境中，以及战略设计的井位相对于断层的方向和方向的运动，可以帮助减轻诱发的地震灾害。
Over 100 small- to moderate-sized earthquakes, including an Mw 5.0 event, were detected during September 2015 to November 2016 near the town of Cushing, Oklahoma. The seismic sequence was spatial-temporally linked to four wastewater disposal wells within 4 km. We calculate pore pressure and stress perturbations caused by fluid injection at multiple wells and analyze seismic risk in a Coulomb failure stress framework. Despite being more than an order of magnitude smaller than the pore pressure perturbation, the sign of shear stress change, in the sense of assumed right-lateral fault motion, dictates where earthquakes are induced. Most of the relocated earthquakes are located within areas of positive shear stress changes. Our results suggest that poroelastic stress changes also play an essential role in the wastewater disposal environment, and a strategic design of well locations with respect to fault orientation and direction of motion can help mitigate induced seismic hazard.