18 TERTIARY AND QUATERNARY PECTENS OF CALIB'ORNIA. 



VAQUEROS SANDSTONE. 

 TYPE LOCALITY. 



The type localitj' i.s Los Vaqueros Valley, Monterey County, Cal. 



NAMK AND DESCRIPTION. 



This formation name was suggested Ijy Mr. Homer Hamlin and first used by 

 Dr. H. W. Fairbanks in the descriptive text of the San Luis folio (California), 

 1904, p. 3. 



DEFINITION. 



The Vaqueros sandstone lies conformably beneath the Monterej' shale and 

 rests conformably upon the San Lorenzo formation and unconformably upon the 

 Tejon (Eocene) or older formations. It varies in thickness iu diflerent localities, 

 its maxinmm lieing between 2,000 and 3.000 feet. 



LOCALITIES. 



Martinez, Contra Costa Connty. 



Mount ]>ia))Io Ran^e in Contra Costa and Alameda counties. 



Santa Cruz Mountains, in San Mateo, Santa Clara, and Santa Cruz counties (Mindego Creek, Stevens 



Creek, Boulder Creek, etc.). 

 Los Vaqueros Valley and Santa Lucia Range, Monterey t!ounty. 

 Lynchs Mountain, Corral de Piedra Creek, Hazzard Canyon, Morro Creek, La Panza, and Toro Creek 



San Luis Obispo County. 

 Barker's ranch (Kern River), Poso Creek, San Emidio Canyon, 6 miles southeast of Annette, and 



Avenal Canyon, Kern County. 

 San Miguel Island and Santa Inez Mountains, Santa Barbara County. 

 Ojai Valley, Sespe oil clistrict, and Santa Monica Mountains, ^'eIltura County. 

 Santa Monica Mountains, Eagle Rock Valley, and Pasadena, Los Angeles County. (This formation 



may also be younger than the Vaqueros. ) 

 Santa .\na INlountain.s and El Toro. Orange County. 

 Carrizo Creek, San Diego County (?), (Prol)ably younger than the Vaqueros.) 



According to Merriam, tlie lower Miocene or Agasoinu zone occurs in 

 Oregon, and the same horizon is probabl}' represented still farther north by a 

 part of the Oligocene-Miocene series of Washington. 



FAUNA. 



The Vaqueros has a very characteristic fauna, consisting of numerous forms 

 peculiar to itself besides many species found in the overlying formations. A few 

 Vaqueros species are found in the transitional beds between it and the San 

 Lorenzo (Oligocene), but none of the members of its fauna, so far as known 

 reach into the Tejon (Eocene). On account of the occurrence of species of the 

 peculiar genus Agasoma in the lower Miocene, Doctor Merriam lias given it the 

 appropriate name "^(/a.NOw^tf zone." " He has tentatively divided this into two 

 stages; the probably lower of the two characterized by TiirriteUa hoffinaiini and 

 the upper by Turritella ocoymia. No diflerentiation of the two stages is attempted 

 in this paper. 



Pecten fauna. — The Pecten fauna of the Vaqueros sandstone or Ayasoma 

 zone is a large one and consists of the following species: P. andersoni, P. andersoni 



a Bull. Dept. Geol. Univ. Cnl., vol. .S, 1904, y.. 378. 



