Induced seismicity is strongly related to various engineering projects that cause anthropogenic in-situ stress change at a great depth. Hence, there is a need to estimate and mitigate the associated risks. In the past, various simulation methods have been developed and applied to induced seismicity analysis, but there is still a fundamental difference between simulation results and field observations in terms of the spatial distribution of seismic events and its frequency. The present study aims to develop a method to simulate spatially distributed on-fault seismicity whilst reproducing a complex stress state in the fault zone. Hence, an equivalent continuum model is constructed, based on a discrete fracture network within a fault damage zone, by employing the crack tensor theory. A fault core is simulated at the center of the model as a discontinuous plane. Using the model, a heterogeneous stress state with stress anomalies in the fault zone is first simulated by applying tractions on the model outer boundaries. Subsequently, the effective normal stress on the fault plane is decreased in a stepwise manner to induce slip. The simulation result is validated in terms of the b-value and other seismic source parameters, hence demonstrating that the model can reproduce spatially and temporally distributed on-fault seismicity. Further analysis on the parameters shows the variation of frequency-magnitude distribution before the occurrence of large seismic events. This variation is found to be consistent with field observations, thus suggesting the potential use of this simulation method in evaluating the risk for seismic hazards in various engineering projects.

诱发地震活动与引起大深度人为地应力变化的各种工程项目密切相关。因此，需要估计和减轻相关风险。过去，已经开发了多种模拟方法并将其应用于诱发地震活动性分析，但模拟结果与现场观测在地震事件的空间分布及其频率方面仍然存在根本差异。本研究旨在开发一种方法来模拟空间分布的断层地震活动，同时再现断层带中的复杂应力状态。因此，利用裂纹张量理论，基于断层破坏带内的离散裂缝网络，构建了一个等效的连续体模型。断层核心在模型的中心被模拟为一个不连续的平面。使用该模型，首先通过在模型外边界上施加牵引力来模拟断层带中具有应力异常的异质应力状态。随后，断层面上的有效法向应力逐步减小以诱发滑动。仿真结果在以下方面得到验证b值和其他震源参数，从而证明该模型可以再现时空分布的断层地震活动。进一步分析参数可知在大地震事件发生前频率-幅度分布的变化。发现这种变化与现场观察一致，因此表明这种模拟方法在评估各种工程项目中地震灾害风险方面的潜在用途。