Li Ziyan, Eaton David W, Davidsen Jörn
Department of Geoscience, University of Calgary, Calgary, AB T2N 1N4 Canada.
Department of Physics and Astronomy, University of Calgary, Calgary, AB T2N 1N4 Canada.
Sci Rep. 2023 Aug 12;13(1):13133. doi: 10.1038/s41598-023-40403-2.
Short-term forecasting of estimated maximum magnitude ([Formula: see text]) is crucial to mitigate risks of induced seismicity during fluid stimulation. Most previous methods require real-time injection data, which are not always available. This study proposes two deep learning (DL) approaches, along with two data-partitioning methods, that rely solely on preceding patterns of seismicity. The first approach forecasts [Formula: see text] directly using DL; the second incorporates physical constraints by using DL to forecast seismicity rate, which is then used to estimate [Formula: see text]. These approaches are tested using a hydraulic-fracture monitoring dataset from western Canada. We find that direct DL learns from previous seismicity patterns to provide an accurate forecast, albeit with a time lag that limits its practical utility. The physics-informed approach accurately forecasts changes in seismicity rate, but sometimes under- (or over-) estimates [Formula: see text]. We propose that significant exceedance of [Formula: see text] may herald the onset of runaway fault rupture.
估计最大震级([公式:见正文])的短期预测对于减轻流体激发期间诱发地震活动的风险至关重要。以前的大多数方法都需要实时注入数据,但这些数据并非总是可用。本研究提出了两种深度学习(DL)方法以及两种数据划分方法,它们仅依赖于先前的地震活动模式。第一种方法直接使用深度学习预测[公式:见正文];第二种方法通过使用深度学习预测地震活动率来纳入物理约束,然后用该地震活动率来估计[公式:见正文]。使用来自加拿大西部的水力压裂监测数据集对这些方法进行了测试。我们发现,直接深度学习方法从先前的地震活动模式中学习以提供准确的预测,尽管存在时间滞后,这限制了其实际效用。基于物理原理的方法准确地预测了地震活动率的变化,但有时会低估(或高估)[公式:见正文]。我们提出,[公式:见正文]的显著超过可能预示着失控断层破裂的开始。