Lithology and Stratigraphy This subsection contains mainly
Tertiary sedimentary rocks and Quaternary marine sediments. The
Tertiary rocks are Eocene marine and nonmarine and Miocene and
Pliocene marine sedimentary rocks. There are many small areas of
late Quaternary fluvial deposits. This is a subsection of nearly
level to very gently sloping marine terraces that have been
eroded and dissected to expose Tertiary sedimentary rocks. The
dissected terrace edges are moderately steep to steep. There is
a narrow strip of beach and dune sand along the coast. Some
streams have deposited recent alluvium in ponds behind sand
bars. The subsection elevation range is from sea-level to about
1500 feet. Mass wasting, coastal marine, and fluvial erosion and
deposition are the main geomorphic processes. The soils are
mostly Alfic Xeropsamments, Typic Natrixeralfs, and Abruptic
Durixeralfs on the marine terraces and Lithic Xerorthents,
Lithic and Calcic Pachic Haploxerolls, Typic Argixerolls, Typic
Haploxeralfs, Typic Natrixer