1915] 



Clark: Fauna of the San Pablo Group 



393 



GEOGRAPHIC OCCURRENCE OF THE SAN PABLO GROUP 



Beds equivalent to the San Pablo Group in California are fairly 

 widespread throughout the Coast Ranges, though they have not been 

 generally recognized under this name. Marine beds of San Pablo age 

 are, so far as known, absent on the east side of the Great Valley along 

 the base of the Sierra Nevada. Deposits of this age are known more 

 or less continuously throughout the Coast Ranges, from a little north 

 of San Francisco Bay to as far south as Santa Barbara, Santa Barbara 

 County, beyond which they have not been certainly recognized. 



From north of San Francisco Bay, C. E. Weaver 10 listed five 

 species of invertebrates from the San Pablo, and V. C. Osmont, 11 in a 

 paper entitled. "A Geological Section of the Coast Ranges North of 

 the Bay of San Francisco," also recognized the San Pablo. The 

 northern limit of the group is not known. 



On the east side of the Coast Ranges along the Mount Diablo 

 Range, the San Pablo Group is known at least as far south as Tesla 

 or Corral Hollow. The geology of the region from Corral Hollow 

 southward for a distance of over one hundred miles is not known in 

 detail. In the region of Coalinga, beds ecpiivalent to only a part of 

 the San Pablo Group have been described by Ralph Arnold, Robert 

 Anderson, Harry Johnson, F. M. Anderson 12 and others, under the 

 name "Santa Margarita." The San Pablo group is known on the 

 east side of the Coast Ranges as far south as the southern end of the 

 San Joaquin Valley. 



On the west side of the Coast Ranges, the San Pablo Group extends 

 more or less interruptedly from the Santa Cruz Mountains, 13 in Santa 

 Cruz County, southward through Monterey County to at least as far 

 south as the town of Santa Barbara. 



10 Univ. Calif. Publ. Bull. Dept. Geol., vol. 5, no. 16, pp. 243-269, 1909. 



11 Univ. Calif. Publ. Bull. Dept. Geol., vol. 4, no. 3, 1909. 



12 Arnold, Ealph, and Anderson, Robert, Geology and oil resources of 

 Coalinga, U. S. G. S. Bull. 398, 1910. 



Arnold, Ealph, and Johnson, Harry, A preliminary report on the McKittrick- 

 Sunset oil region, Kern and San Luis Obispo counties, California, U. S. G. S. 

 Bull. 406, 1910. 



Anderson, Robert, Preliminary Report on the geology and oil prospects of 

 the Cantua Panoche region, California, U. S. G. S. Bull. 431-A, pp. 54-83, 1911. 



Anderson, F. M., A stratigraphic study in the Mount Diablo Range of Cali- 

 fornia, Proc. Calif. Acad. Sci., 3d series, Geol., vol. 2, no. 2, 1905. 



Anderson, F. M., A further study in the Mount Diablo Range of California, 

 Proc. Calif. Acad. Sci., 4th series, vol. 3, pp. 1-40, 1908. 



is Santa Cruz Folio, no. 163, p. 5, 1909. 



