WESTSIDE - SOUTH
Published:January 01, 1990
During the upper Miocene the southern San Joaquin Valley underwent rapid structural changes. Localized uplift shed coarse-grained quartz-rich sands into the subsiding Maricopa depocenter, in the form of deep marine turbidites. These upper Miocene turbidites in the southern portion of the San Joaquin basin are collectively referred to as the “Stevens” sands.
First encountered in a well drilled in 1936, the Stevens turbidite sands have become a major oil exploration target. A schematic model for the sand-rich Stevens turbidite deposition is used to examine four producing fields within the Maricopa depocenter. Examples of sand-rich turbidite morphology, seismic signatures, depositional styles, and lateral migration of channel-lobe systems will be presented to demonstrate the effect of upper Miocene structural growth upon Stevens deposition within the Maricopa depocenter.