Bradley G. Erskine, H.-R. Wenk; Evidence for Late Cretaceous crustal thinning in the Santa Rosa mylonite zone, southern California. Geology ; 13 (4): 274–277. doi: https://doi.org/10.1130/0091-7613(1985)13<274:EFLCCT>2.0.CO;2
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The Santa Rosa mylonite zone is part of a 100-km-long belt of deformation along the eastern margin of the northern Peninsular Ranges batholith, southern California. In the northern Santa Rosa Mountains, complexly deformed mylonitic plutonic and metasedimentary tectonites are cut by a stacked sequence of five low-angle faults. Evidence from field relationships and the analysis of minor structures, microstructures, and textures (preferred orientation) suggest that the coaxial component of deformation (“pure shear”) dominated over a noncoaxial (“simple shear”) component. It is proposed that mylonitic deformation and low-angle faulting, which appear to be kinematically associated, are the result of Late Cretaceous extension and thinning of the continental margin.