Sawtooth segmentation and deformation processes on the southern San Andreas Fault, California

Abstract

Five contiguous 12‐13 km fault segments form a sawtooth geometry on the southernmost San Andreas fault. The kinematic and morphologic properties of each segment depend on fault strike, despite differences of strike between segments of as little as 3 degrees. Oblique slip (transpression) of fault segments within the Indio Hills, Mecca Hills and Durmid Hill results from an inferred 8:1 ratio of dextral slip to convergence across the fault zone. Triggered slip and creep are confined almost entirely to transpressive segments of the fault. Durmid Hill has been formed in the last 28 ± 6 ka by uplift at an average rate of 3 ± 1 mm/a.

The Burst‐Like Behavior of Aseismic Slip on a Rough Fault: The Creeping Section of the Haiyuan Fault, China

“…Such a correlation between local azimuth of the fault and average creep rate along strike over the 2003-2009 period has already been observed by Jolivet et al (2013). In addition, segments of similar length are often identified along major continental strike-slip faults in relationship with their seismic behavior (10-15 km long; e.g., Bilham and Williams, 1985;Klinger, 2010).…”

Triggered Surface Slips in the Salton Trough Associated with the 1999 Hector Mine, California, Earthquake

“…Areas where surface breaks formed lie in uplifted Pleistocene fine-grained lacustrine and fluvial deposits. See Bilham and Williams (1985) for discussion of structural relations to triggered slip occurrence and Rymer (2000) for discussion of distribution of triggered slip and local geologic materials.…”

Tectonics of strike-slip restraining and releasing bends

“…Thus, bends are characterized by oblique deformation that is ultimately controlled by larger-scale relative plate motions either acting on relatively straight, long interplate boundaries (Garfunkel 1981;Mann et al 1983;Bilham & Williams 1985;Bilham & King 1989) or acting across more complex zones of intraplate deformation where faults tend to be shorter, less continuous and more arcuate (Cunningham this volume). Within the bend, oblique deformation may be accommodated by oblique-slip faulting or partitioned into variable components of strike-slip and dip-slip fault displacements (Jones & Tanner 1995;Dewey et al 1998;Cowgill et al 2004b;Gomez et al this volume).…”