Fig. 9: Strain partitioning across the San Andreas fault system.
From: Mantle flow distribution beneath the California margin
The top panel shows the plate parallel velocity from the integration of the shear component of the strain-rate tensor in the plate-perpendicular direction. The dashed lines indicate the average velocity and (1-σ) standard deviation of the Pacific plate relative to the North American plate from 18 different models, including REVEL-2000, NUVEL 1A, ITRF 2008, and MORVEL 2010 (refs. 76,77,78,79). The bottom panel shows the distribution of deep shear strain-rate in California from the Mendocino triple junction to the Salton trough, highlighting the strain partitioning primarily between the San Andreas fault and the Eastern California Shear Zone. The red stars and black circles show the hypocenter of historical earthquakes and earthquakes from moment magnitude 3 and above from 1990 to 2020 around California, respectively. The seismic catalog is obtained from the Northern California Earthquake Data Center (https://ncedc.org) and the Southern California Earthquake Data Center (https://scedc.caltech.edu). The gray dashed profiles correspond to the 5-km depth contours of the Cascadia megathrust. Red triangles indicate quaternary volcanos.
