Abstract This study uses work optimization to predict the spatial and temporal development of faults. We focus on the growth of small fractures that develop into thrust faults at the toe of accretionary prisms because observations from physical laboratory accretion experiments provide rich data with which to validate the models, and the processes of accretionary thrust fault initiation remain unclear. In order to model these systems, we apply new implementations to the fault growth code GROW that improve its prediction of fault interaction using work optimization, including: 1) CPU parallelization, 2) a new growth algorithm that propagates only the most efficient fault in each growth increment, the single run mode, and 3) a new growth algorithm that only considers fault propagation from fault tips that host high sums of modes I and II stress intensity factors, KG, the limiting mode. The new single and limiting mode produce the geometries that best match the observed geometries, rather than the algorithm that allows all the faults to propagate simultaneously, regardless of KG, the multiple and non-limiting mode. The single limiting models predict that frontal accretionary thrusts initiate at the midpack or shallower depths, consistent with findings of previous studies. The thrusts propagate upward, link with the surface, and then propagate downward and link with the detachment. The backthrust tends to propagate before the forethrust, and then influences the forethrust propagation. This temporal and spatial sequence of faulting arises from the lower compression, higher shear strain, higher Coulomb stress and higher strain energy density that develop near the wedge surface and the inflection of the wedge slope. The models reveal that the final slip distributions do not reliably indicate the initiation location of the faults, in contrast to widespread assumptions.

中文翻译：

---

通过工作优化预测正面增生逆冲断层的传播和相互作用

摘要 本研究使用工作优化来预测断层的时空发展。我们专注于在增生棱柱的趾部发展成逆冲断层的小裂缝的生长，因为物理实验室增生实验的观察提供了丰富的数据来验证模型，并且增生逆冲断层的萌生过程尚不清楚。为了对这些系统进行建模，我们对故障增长代码 GROW 应用了新的实现，使用工作优化来改进其对故障交互的预测，包括：1) CPU 并行化，2) 一种新的增长算法，该算法仅传播每个中最有效的故障增长增量，单次运行模式，和 3) 一种新的增长算法，它只考虑来自故障尖端的故障传播，这些故障尖端承载着大量的模式 I 和 II 应力强度因子 KG，即限制模式。新的单一和限制模式产生与观察到的几何最匹配的几何，而不是允许所有故障同时传播的算法，无论 KG，多重和非限制模式。单一限制模型预测正面增生推力在中层或更浅的深度开始，与先前研究的结果一致。推力向上传播，与地表相连，然后向下传播，与脱离相连。后推力往往先于前推力传播，进而影响前推力传播。这种断层作用的时间和空间序列是由楔形表面附近和楔形斜坡的拐点产生的较低的压缩、较高的剪切应变、较高的库仑应力和较高的应变能量密度引起的。模型表明，与普遍的假设相反，最终的滑动分布不能可靠地表明断层的起始位置。