1913] 



Louderbach: 



The Monterey Scries 



209 



they are either charaeteristic of the "shale facies" or are found 

 in the Vaqueros (or Temblor, which he considers equivalent). 

 He admitted that "As suggested by Doctor Lawson, the shale 

 probably has an inshore equivalent of sandstone, whose fauna is 

 doubtless entirely different from that of the shale and probably 

 shows a marked resemblance 7 ' to that of the underlying Vaqueros 

 and overlying Contra Costa County Miocene." This hypothet- 

 ical marked resemblance is, however, apparently not considered 

 to amount to identity, and the two depositions 1 facies are pre- 

 sented as independent formations representing different time 

 intervals. The upper faunal zone of the littoral facies described 

 by Merriam (loc. tit.) is evidently misinterpreted as a formation 

 "lying between the Monterey shale and the San Pablo," and 

 called by Arnold (supposedly after Merriam, though I can learn 

 of no such usage) the "Contra Costa County Miocene." 



Santa Clara Valley Oil Fields, Eldridge and Arnold, 1907. — 

 The year 1907 produced a rich harvest of California Tertiary 

 literature in the form of bulletins on the oil districts of the 

 Southern Coast Ranges. The first 51 of these was on "the Santa 

 Clara Valley, Puente Hills and Los Angeles Oil Districts. ' ' The 

 part on the Santa Clara Valley district has already received 

 considerable attention in Part I of the present paper and need 

 not be discussed at length here. It is noteworthy in adding to 

 the Vaqueros sandstone the terrigenous shales and limestones 

 and a certain fraction of the siliceous shales (all previously 

 assigned to the Monterey by Fairbanks and others) because in 

 the lower part there was found within them a "Vaqueros fauna," 

 the name being appropriately changed to "Vaqueros formation" ; 

 and in the creation of a "Modelo formation" including the resi- 

 due of siliceous shales and certain intercalated sandstones, the 

 base of the Modelo being placed at "the sharp line" between 

 the underlying siliceous shale and the Modelo sandstone. How- 

 ever, on the south of the valley and in the western part of the 

 field, the line is drawn between siliceous shale and underlying 

 terrigenous beds following the usage of others. This field is a 



so Italics not in the original. 



si U. S. Geol. Surv. Bull., 309 (1907). 



