Earthquake moment tensors can be decomposed into double‐couple components describing slip on planar faults and non‐double‐couple (NDC) components. NDC components can arise in three ways. Some appear to be intrinsic, indicating complex source processes differing from slip on a fault for earthquakes in specific geologic environments, notably volcanic areas. Others are additive, reflecting the combined effect of double‐couple sources on multiple faults with different geometries. Alternatively, they may be artifactual, results of the inversion without geologic meaning. Combining moment tensors from three global and four regional catalogs for 2016–2020 provides a dataset of NDC components of 12,856 earthquakes with 2.9展开▼
