SEA BEAI,I SURVEY OF AN ACTIVE STRIKE-SLIP FAULT: THE SAN CLEMENTE FAULT IN THE CALIFORNIA CONTINENTAL BORDERIAND

Abstract. The San Clemente fau1t, located in the Cal i fornia Cont inental Border land, is an act ive, northwest t rending, r i8ht- latera1, wrench faul t, Sea Beam data are used co map the najor tectonic landforms associated wi th act ive submarine faul t ing in detai l unavai lable using convent ional echo-sounding or seismic ref lect ion data. In the area between North San Clemente Basin and Fortymi le Bank, the major late Cenozoic faul ts are del ineated by al ignments of nunerous tectonic landforms, i nc l ud ing sca rps, l i nea r t r enches, benches, and sags. Character and spat ia l pat terns of these landforms are consistent r, r i th dextra l wrench faul t ing, a l though vert ical of fsets rnay be substan-t ia l local ly. The main t race of the San Clemente faul t cuts a stra ight path di rect ly across the rugged topography of the region, evidence of a s teep l y d i pp ing f au l t su r f ace. Bas ins o r sags located at each r ight step in the en echelo