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University of Calif orma Puhlicatious in Geology [Vol. 12 



beds of rather coarse greenish sandstones often conglomeratic, ill 

 sorted, and cemented by a fine muddy sandstone. Where the Vaqueros 

 rests upon the Sespe, as on the east side of Oso Caiion, Loma Alta, 

 and in the vicinity of Mateo Creek, no Turrit ella inezana fauna was 

 obtained, and the lowest beds contained TiirriteUa ocoyana. More- 

 over, the Vaquero.s consisting of coarse brownish sandstone, somewhat 

 conglomeratic in places, grades down into the underlying Sespe with 

 no indication of an unconformity. 



The usual lithologic section of the Vaqueros consists of a heavy 

 fossiliferous conglomerate at the base, followed by coarse gray to 

 brown massive sandstones, which weather out into prominent strike 

 ridges. This type of sandstone is a characteristic feature of the 

 region on the south side of the Santa Ynez River above the Los 

 Prietos ranger station, and as far east as the Cold Spring trail. Near 

 the top of these sandstones, a twenty-foot bed of impure light gray to 

 nearly white limestone may be traced from east of Blue Canon to 

 Oso Creek. It also forms a prominent feature in the syncline which 

 lies immediatel^y north of the Santa Ynez River in the vicinity of 

 Mono Creek. The following fauna has been obtained from this lime- 

 stone : 



Cassidulus (Rhyncliopygus) yiiezanus Kew (Ms.) 

 Cassidulus (Rhyncliopygus) elliptieus Kew (Ms.) 

 Seutella, cf. merriami Arnold 

 Pec ten, sp. 

 Spiroglyphus, sp. 

 Ostrea, sp. 



Turritella ocoyana Conrad 

 Terebratalia kennedyi Dall 



Above the massive sandstones, sandy shales predominate, with inter- 

 bedded layers of nodular muddy sandstones containing a Turritella 

 ocoyana fauna. These shales weather bluish on the surface, but on 

 fresh fractures the color is black, due to their impregnation by 

 petroleum. The main body of these petroliferous shales is located in 

 the Santa Ynez River east of ]Mateo Canon. AVhere these strata are 

 not bituminous, the color is usually a light orange or yellow. They 

 are quite soft, and characterized by lenses and nodules of calcareous 

 fine-grained sandstone which contain a Turritella ocoyana fauna. 



Salinas shale. — No sharp line can be drawn between the Salinas 

 shale and the Vaqueros, though the change in rocks is striking. 

 The lower part of the Salinas shale is characterized by white clay 



