Evolution of the central Garlock fault zone

The slip rate of the Garlock fault in southeastern California has accelerated through time to the modern rate of 9 mm per year.

Left-lateral strike-slip displacement of 64 km on the Garlock fault began 11 million years ago as an accommodation structure to Basin and Range extension. The Garlock fault subsequently changed geometry and rates when dextral shear initiated inboard of the San Andreas plate boundary.

The Garlock fault evolved to a structurally more complex fault zone to accommodate the transversely oriented dextral shear. Dextral shear across the Garlock fault is accommodated by internal deformation within the Garlock fault zone via lateral extrusion, uplift, folding, internal block rotation, and counterclockwise rotation of its trace.

Evolution of the central Garlock fault zone, California: A major sinistral fault embedded in a dextral plate margin Joseph E. Andrew et al., Dept. of Geology, University of Kansas, Lawrence, Kansas 66045, USA. Published online 26 Aug. 2014; http://dx.doi.org/10.1130/B31027.1.