PLEISTOCENE HISTORY OF THE NEWPORT BAY AREA, SOUTHERN CALIFORNIA
BY STEPHEN C. BRUFF*
The only Pleistocene beds exposed in this area are equivalent in age and lithology to those of the Palos Verdes sands of the San Pedro area. They are largely undeformed and lie unconformably as a capping bed over the folded Tertiary rocks that make up the Costa Mesa.
The water temperature of Palos Verdes time in this area, as indicated by a fauna of 169 species of marine mollusks, was approximately 3.4°F. warmer than the present littoral temperatures. A fauna of similar species might be found living today along the coast off Cape Colnett, Lower California.
Two types of beaches occurred in this area: protected shores, primarily rocky, along the sea cliff that existed at the base of the San Joaquin Hills; and the bays and estuaries that appeared from time to time in conjunction with the . . .