Exploring Spatial Coherence between Earthquake Source Parameters

We explore the spatial coherence between earthquake source parameters by analyzing kinematic rupture models of two large strike-slip events, that is, the 1999 Izmit, Turkey, and the 1992 Landers, California, earthquakes. We investigate the coherence not only at zero offset but also at nonzero offset distances on the fault. The analysis shows that earthquake slip has a significant level of correlation with temporal source parameters such as rupture velocity, peak slip rate, and slip duration (rise time). We also show that many interesting features of earthquake source characteristics, such as directional effects of earthquake rupture, can be captured by this type of spatial coherence analysis. A coherence analysis therefore may have potential for understanding earthquake source characteristics and for generating realistic kinematic rupture models that capture the essential physics of the rupture process for strong ground motion prediction.