National Geologic Map Database
Map showing publication footprint
  • Usage in publication:
    • Kreyenhagen shale
  • Modifications:
    • Revised
  • AAPG geologic province:
    • San Joaquin basin

Jenkins, O.P., 1931, Stratigraphic significance of the Kreyenhagen shale of California: California Journal of Mines and Geology, v. 27, no. 5, p. 141-186.


Pg. 141-149. Kreyenhagen shale. A dual type locality was originally given for Kreyenhagen shale. The name was applied to shales on Reef Ridge, south of Coalinga, lying between Avenal and Temblor sandstones, whereas the originally collected Foraminfera employed to determine the age of the Kreyenhagen came from shales north of Coalinga, beneath Domengine sandstone. The Federal Survey, however, in area north of Coalinga, mapped as Kreyenhagen the series of diatomaceous strata lying above the "Tejon" (Domengine) and below the "Vaqueros" (Temblor). In this series are now found 2 unconformities which divide it into 3 distinct units and account for previous conflicts in stratigraphic correlation. The upper unconformity is at base of Leda zone (probably Oligocene), which zone, 0 to 150 feet thick, lies unconformably beneath Temblor sandstone and unconformably on shale and sandstone of Oligocene or Eocene age, which is eroded away in places. The name Kreyenhagen, as used in present discussion, represents certain organic shales (not yet definitely assigned to any one age, though probably Eocene or possibly Oligocene) lying disconformably on hilly western side of San Joaquin Valley, above known Eocene sandstones and sandy shales (variously called Domengine, Tejon, Meganos, or Martinez?). They contain white diatomite beds at top. The Kreyenhagen is not known to be Eocene, but inference is made by writer that it is probably = type Tejon, which is definitely Eocene. Writer places upper boundary of Kreyenhagen shale at first unconformity encountered, the unconformably overlying beds in Cantua-Panoche region consisting of sandstone and shale of Eocene or Oligocene age. This shale series is considered by writer to include more strata north of Coalinga than it does farther south on Reef Ridge, on Kreyenhagen Ranch, where Kreyenhagen wells are located, but it is correlated, without hesitancy, by writer with the siliceous phase of Kreyenhagen shale of Reef Ridge and Canoas Creek, regarded as first type locality of formation. On Reef Ridge writer is inclined to place lower boundary of Kreyenhagen at base of the siliceous shale and above the sandy clay zone in which diagnostic Eocene fossils (Foraminifera and Mollusca) have been found in abundance. The beds above this sandy clay zone are siliceous.

Source: US geologic names lexicon (USGS Bull. 896, p. 1121-1122).

For more information, please contact Nancy Stamm, Geologic Names Committee Secretary.

Asterisk (*) indicates published by U.S. Geological Survey authors.

"No current usage" (†) implies that a name has been abandoned or has fallen into disuse. Former usage and, if known, replacement name given in parentheses ( ).

Slash (/) indicates name does not conform with nomenclatural guidelines (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). This may be explained within brackets ([ ]).