During late Cenozoic Era , because of sustained transpression of the Pacific Plate onto the American Plate along the nearby San Andreas Fault Zone , there was continued uplift of the entire coastline of California , so that erosive action of marine waves cut these terraces in the Monterey Bay area . Those Pleistocene marine terraces are composed of clay , silt , sand and gravel with a basal unconformity of gravel on top of rock . The creation of uplifted marine terraces that started to appear during the Pleistocene Epoch continues throughout the ( present ) Holocene Epoch of the Quaternary Period due to transpression of the Pacific Plate onto the American Plate . During the October 1989 Loma Prieta earthquake , the marine terraces of the Monterey Bay were further uplifted . Both Monterey and Santa Cruz have classical uplifted wave-cut shorelines with multiple sets of uplifted and exposed marine terraces
1989 Loma Prieta earthquake
1989 Loma Prieta earthquake
Geological history of Point Lobos