Observations in tectonically active areas increasingly reveal sets of high-angle conjugate faults (‘cross-faults’) that apparently contradict theories of faulting based on experimental data. Possible explanations include a low in situ coefficient of friction, dominant control of ductile shear zones in the lower crust, and tectonic rotation. Discrimination between these mechanisms has been hindered by uncertainties in the state of stress, deformation history and fault geometry at seismogenic depths. Here we use a combination of seismic, geodetic and geologic data to demonstrate that ubiquitous cross-faults in the Ridgecrest (California) area, including those ruptured in the sequence of strong earthquakes in 2019, result from rotation from an initially optimal orientation consistent with experimental data. The inferred rotation pattern can be explained by the geodetically measured velocity field. Our model suggests that the observed asymmetric rotation of faults in the Eastern California Shear Zone can result from simple shear. The same mechanism can be responsible for high-angle conjugate faults observed in other tectonic settings.

在构造活动区的观察越来越多地揭示出明显与基于实验数据的断层理论相矛盾的高角度共轭断层（“交叉断层”）。可能的解释包括低原地摩擦系数、下地壳韧性剪切带的主要控制以及构造旋转。应力状态、变形历史和发震深度断层几何形状的不确定性阻碍了这些机制之间的区分。在这里，我们结合地震、大地测量和地质数据来证明，加利福尼亚州里奇克莱斯特地区普遍存在的交叉断层，包括在 2019 年强地震序列中破裂的断层，是从与实验一致的初始最佳方向旋转产生的数据。推断的旋转模式可以通过大地测量速度场来解释。我们的模型表明，观察到的东加州剪切带断层的不对称旋转可能是由简单的剪切引起的。在其他构造环境中观察到的高角度共轭断层可能是相同的机制。