Full Title: Evolution of Ridge Basin, Southern California: An Interplay of Sedimentation and Tectonics
Editor: John C. Crowell
Ridge Basin, a complex, pull-apart basin within the San Andreas transform belt of southern California, contains more than 14,000 m of marine and nonmarine strata in a tilted sequence. As the basin opened and enlarged during the Late Miocene, coarse sedimentary breccias and conglomerates derived from uplifted sources at basin margins were displaced dextrally by the San Gabriel and older Canton faults. Basin facies demonstrate close interplay between continuing deformation and deposition as depocenters move laterally. Major displacements on the modern San Andreas fault in the Pliocene followed and truncated Ridge Basin on the north. Concomitantly, the region was uplifted and deeply eroded so that the evolution and history of the basin and its setting is now well revealed.