Abstract: Magnetic Stratigraphy of the Type Zemorrian Stage (Oligocene), Lower Temblor Formation, Temblor Range, Kern County, California

RESSEGUIE, JENNIFER L., and DONALD R. PROTHERO

Kleinpell (1938) erected the Zemorrian stage based on benthic foraminifera from the lower Temblor Formation in Zemorra Creek, southern Temblor Range, Kern County, California. The correlation of the Zemorrian stage with the standard time scale has long been controversial, although most authors have considered it to represent some part of the Oligocene. Paleomagnetic samples were taken from the type Zemorrian in and near Zemorra Creek. The magnetic directions passed both a fold and reversal test, and remanence seems to be held by both magnetite and hematite. The lowest members, the Cymric Shale and the overlying Wygal Sandstone, contain early Zemorrian foraminifera and were entirely reversed in polarity. Based on the occurrence of early Zemorrian fossils associated with P19 planktonic foraminifera in the San Lorenzo Formation, we correlate the Cymric and Wygal members with Chron C12r (31.0-33.0 Ma). The late Zemorrian Saints Shale and Agua Sandstone produce a reversed-normal-reversed pattern that could correlate with four different magnetic sequences, since the age control is so poor. However, no matter how one interprets the correlation, it is clear that the type Zemorrian is very incomplete and spans at most 2-3 million years of the 10 million years of the Oligocene (which lasts from 24.0 to 33.7 Ma).

Search and Discovery Article #90945©1997 AAPG Pacific Section Meeting, Bakersfield, California