Shear stress levels on reverse faults are anticipated to be several times higher than on normal faults with the same pore pressure ratio. In addition, ruptures on normal faults release gravitational potential energy, whereas earthquakes on reverse faults expend work in uplifting rocks. In this study, I investigate the significance of these differences for earthquake cycles and I question whether the source of energy driving earthquakes is the same on reverse and normal faults. Based on the assumption that normal and reverse faults have the same background frictional properties and pore pressure states, I use numerical simulations with a two-dimensional dynamic elastic-plastic model to show that due to stress differences, earthquakes on reverse faults tend to occur less frequently, produce more coseismic slip and stress drop and involve higher slip rates than ruptures on normal faults with equivalent dimensions. The analysis also shows differences in the energy changes associated with earthquake cycles on reverse and normal faults. However, the earthquakes on both fault types result from abrupt release of elastic strain energy, which proceed and essentially drive variations in gravitational potential energy. Thus, ruptures on both normal and reverse faults are consistent with elastic rebound theory.

中文翻译：

---

基于动态弹塑性模型模拟比较正断层和逆断层的地震周期


预计反向断层上的剪切应力水平比具有相同孔隙压力比的正断层高几倍。此外，正断层上的破裂会释放重力势能，而逆断层上的地震会消耗抬升岩石的功。在这项研究中，我研究了这些差异对地震周期的重要性，并质疑驱动地震的能量来源在逆断层和正断层上是否相同。基于正断层和逆断层具有相同的背景摩擦特性和孔隙压力状态的假设，我利用二维动态弹塑性模型进行数值模拟，结果表明，由于应力差异，逆断层上的地震往往较少发生。通常，与同等尺寸的正常断层破裂相比，会产生更多的同震滑动和应力降，并且涉及更高的滑动速率。分析还显示了逆断层和正断层上与地震周期相关的能量变化的差异。然而，这两种断层类型上的地震都是由弹性应变能的突然释放引起的，弹性应变能的继续发生并本质上驱动了重力势能的变化。因此，正断层和逆断层上的破裂都符合弹性回弹理论。