Abstract

This paper organizes the member lithic unit nomenclature for the San Joaquin basin of California according to “Sequence Stratigraphy” terminology and philosophy of Vail et al (1977)(See Figure 1).

Member units are organized by sequences (See Figure 2) that contain a low-stand system and often, a transgressive/high-stand system. The systems respond to relative eustatic sea level changes. Vail et al (1977) deal with unconformities in the sense that they reflect only erosional events and emphasize the unconformity created during relative sea level drops. This paper pays equal attention to both a transgressive sea level change and a relative sea level drop.

An updated stratigraphic chart shows sand and shale units which are organized by genetic categories relative to sequences and systems tied into a chronological framework based on California benthic foram stages. Twelve complete sequences are defined. Systems are filled with their specific depositional units. The text provides references for most of the lithic units described. Rock names are identified chronologically and then spatially by working from the Stockton arch fault in the north (See Figure 3), to the south end of the San Joaquin basin. Six diagrammatic cross sections are included to aid in illustrating the geologic relationships.