GEOLEX

Summary of Citation: Pismo

Publication:
Fairbanks, H.W., 1904, Description of the San Luis quadrangle
   [California]: U.S. Geological Survey Geologic Atlas of the
   United States, San Luis folio, no. 101, 14 p., scale
   1:125,000

Usage in Publication:
Pismo formation*

Modifications:	Geologic Province:	Dominant Lithology:
Named	California Coast Ranges province	Shale Diatomite Sandstone Conglomerate

Summary:
Named for exposures at town of Pismo, San Luis Obispo Co, CA. Consists of siliceous shale, diatomaceous earth, and thick beds of soft sandstone with a member of sandstone and conglomerate in lower part. Thickness is about 3,000 ft. Occurs in southern part of San Luis quad. Is considered to be contemporaneous with Santa Margarita formation in northern part of area, though the two formations are not known to have been connected. Unconformably underlies Paso Robles formation; unconformably overlies Monterey shale. Is late Miocene age.

Summary of Citation: Pismo

Publication:
Page, B.M., Williams, M.D., Henrickson, E.L., Holmes, C.W. and
   Mapel, W.J., 1944, Geology of the bituminous sandstone deposits
   near Edna, San Luis Obispo County, California: U.S. Geological
   Survey Oil and Gas Investigations Map, OM-16, 1 sheet, scale
   1:24,000

Usage in Publication:
Pismo formation*

Modifications:	Geologic Province:	Dominant Lithology:
Age modified Biostratigraphic dating	California Coast Ranges province

Summary:
Scarcely contains any well-preserved megafossils. Is mainly Pliocene and partly late Miocene in age based on microfossils.

Summary of Citation: Pismo

Publication:
Hall, C.A., Jr., 1973, Geologic map of the Morro Bay South and
   Port San Luis quadrangles, San Luis Obispo County, California:
   U.S. Geological Survey Miscellaneous Field Studies Map,
   MF-511, 1 sheet, scale 1:24,000

Usage in Publication:
Pismo Formation*

Modifications:	Geologic Province:	Dominant Lithology:
Revised	California Coast Ranges province

Summary:
Members named by Hall (1973a) are adopted (ascending): Edna and Miguelito (Miocene and Pliocene age), Gragg, Belleview, and Squire (Pliocene age) as shown on geologic map of Morro Bay South and Port San Luis 7.5' quads, San Luis Obispo Co, CA.

Summary of Citation: Pismo

Publication:
Hall, C.A., Jr., 1973, Geology of the Arroyo Grande 15' quadrangle,
   San Luis Obispo County, California: California Division of
   Mines and Geology Map Sheet, 24, 8 p., 1 sheet, scale
   1:48,000

Usage in Publication:
Pismo Formation

Modifications:	Geologic Province:	Dominant Lithology:
Revised	California Coast Ranges province

Summary:
Divided into (ascending): Edna Member (late Miocene and early Pliocene age), Miguelito Member (late Miocene and early Pliocene age), Gragg Member (late Pliocene age), Belleview Member (late Pliocene age), and Squire Member (late Pliocene age) (all new). Names were tentatively proposed in field guidebook (Hall and Surdan, 1967). Ages are based on included fossils and stratigraphic relations.