Chapter 4: Neotectonics of Santa Cruz Island, California

Jacob A. Selander & Alisha N. Clark

Active tectonics in the Northern Channel Islands typifies the styles of modern deformation taking place in the Western Transverse Ranges. North-south shortening and east-west extension of the Transverse Ranges is a result of transpression south of the Big Bend of the San Andreas Fault. North-south shortening is accommodated via slip along the Channel Islands Thrust, and westward-directed extension through slip along en echelon sinistral faults bisecting the islands. In this paper, the tectonics of the Northern Channel Islands is discussed, focusing on Santa Cruz Island. Structures, styles, and rates of modern deformation are presented and discussed in the context of growth of positive relief on Santa Cruz Island.