An integrated biostratigraphic and paleoecologic study of the Naples Bluff coastal section was completed utilizing diatoms, calcareous nannoplankton, and benthlc foraminifera. This section is 1800 ft. thick and represents one of the most completely exposed marine Neogene sections along the central coast of California.

This sequence contains well preserved diatom floras and benthic foraminiferal faunas that enabled the integration of diatom biochronology with the provincial Miocene benthic foraminiferal stages of Kleinpell (1938, 1980) and the construction of a sediment accumulation curve for the stratigraphic section.

Benthic foraminiferal biofacies provide a detailed analysis of the paleoenvironmental and paleobathymetric history for the sediments of the Naples Bluff section. The biofacies demonstrate that the depositional setting changed several times throughout the section, ranging from lower middle bathyal to upper bathyal. The top of the section shallowed to neritic depths.