NEW PAPER ON BIOSTRATIGRAPHY OF THE SAN JOAQUIN FORMATION

Sorry for the long delay. This past week I had a paper come out on biostratigraphy of the San Joaquin Formation (Pliocene) at the Kettleman City toxic waste dump, North Dome, Kettleman City, Kings County, central California - http://pubs.usgs.gov/of/2010/1140/. The paper is mainly a data dump of fossil occurrences in what was a beautifully exposed section, but which is now being filled with all sorts of nasty stuff. The highlights of the paper are presented below.

The stratigraphic occurrences and interpreted biostratigraphy of invertebrate fossil taxa in the upper San Joaquin Formation and lower-most Tulare Formation encountered at the Chemical Waste Management Kettleman Hills waste disposal facility on the North Dome of the Kettleman Hills, Kings County, California are documented. Significant new findings include (1) a detailed biostratigraphy of the upper San Joaquin Formation; (2) the first fossil occurrence of Modiolus neglectus; (3) distinguishing Ostrea sequens from Myrakeena veatchii (Ostrea vespertina of authors) in the Central Valley of California; (4) differentiating two taxa previously attributed to Pteropurpura festivus; (5) finding a stratigraphic succession between Caesia coalingensis (lower in the section) and Catilon iniquus (higher in the section); and (6) recognizing Pliocene-age fossils from around Santa Barbara. In addition, the presence of the bivalves Anodonta and Gonidea in the San Joaquin Formation, both restricted to fresh water and common in the Tulare Formation, confirm periods of fresh water or very close fresh-water environments during deposition of the San Joaquin Formation.

More to follow soon.

Charles Powell, II