Department of Geophysics, Stanford University, Stanford, CA, 94305, USA.
Department of Geological Sciences, San Diego State University, San Diego, CA, 92182, USA.
Nat Commun. 2018 Sep 26;9(1):3946. doi: 10.1038/s41467-018-06167-4.
Reinjection of saltwater, co-produced with oil, triggered thousands of widely felt and several damaging earthquakes in Oklahoma and Kansas. The future seismic hazard remains uncertain. Here, we present a new methodology to forecast the probability of damaging induced earthquakes in space and time. In our hybrid physical-statistical model, seismicity is driven by the rate of injection-induced pressure increases at any given location and spatial variations in the number and stress state of preexisting basement faults affected by the pressure increase. If current injection practices continue, earthquake hazards are expected to decrease slowly. Approximately 190, 130 and 100 widely felt M ≥ 3 earthquakes are anticipated in 2018, 2019 and 2020, respectively, with corresponding probabilities of potentially damaging M ≥ 5 earthquakes of 32, 24 and 19%. We identify areas where produced-water injection is more likely to cause seismicity. Our methodology can be used to evaluate future injection scenarios intended to mitigate seismic hazards.
与油共生的盐水再注入引发了俄克拉荷马州和堪萨斯州数千次广泛感觉到的和几次破坏性的地震。未来的地震危险仍然不确定。在这里，我们提出了一种新的方法来预测在空间和时间上诱发地震的破坏性概率。在我们的混合物理-统计模型中，地震活动是由任何给定位置的注入引起的压力增加率以及受压力增加影响的预先存在的基底断层的数量和应力状态的空间变化驱动的。如果继续目前的注入实践，地震危险预计将缓慢降低。预计 2018 年、2019 年和 2020 年将分别发生约 190 次、130 次和 100 次广泛感觉到的 M≥3 级地震，相应的潜在破坏性 M≥5 级地震的概率为 32%、24%和 19%。我们确定了可能更容易引发地震的生产水注入区。我们的方法可用于评估旨在减轻地震危险的未来注入方案。
