424 University of California Publications in Geology [Vol. 9 



to half a mile and the three members cross the north line of Twp. 18 S., 

 R. 14 E., with a total width of less than two miles. This is again nar- 

 rowed toward the southeast until in Sec. 23 of this township the upper 

 brown shale and the greater part of the yellow sand has been removed 

 by pre-Tejon erosion, and, south of that point, so far as it occurs, the 

 Martinez is represented beneath the Tejon only by the basal shale with a 

 thin band of yellow sand overlying it through a part of the area. 



Tejon Formation 



The series of sediments here assigned to the Tejon admit of separation 

 into two distinct members; the lower of white sand and conglomerate 

 carrying a fauna in all respects identical with that of the original Tejon 

 locality, and an upper member of white shale which is not so fossiliferous 

 and which, as has been suggested by different investigators in this area, 

 may in part or as a whole represent the Oligocene. 



The general section of the Salt Creek-Cantua region is as follows: 



5. White shale. Feet. 



White fissile organic shales, containing fish scales, teeth, 



foraminifera, etc 500 



Lenses of fine brown sand. 



White shale with local thin sandy strata 1000 



Local friable sand 0-30 



Pink to white shale 200 



Bluish sandy shales grading up into pink shales 40 



1,770 



4. White sandstone and conglomerate. 



Yellowish to white, usually fine sand 100-160 



White massive sandstone and conglomerate with whitish 

 shale inclusions at the base 20-40 



200 



In this portion of the field the base of the Tejon is a fossiliferous 

 conglomerate and sandstone which shows distinct unconformity with the 

 underlying Martinez. Thus, on the east line of Section 17, Twp. 19 S., R. 

 15 E., the base of the conglomerate is upon an oxidized zone and the 

 massive sandy shale immediately below the conglomerate is cut by num- 

 erous burrows that appear to have been made by crustaceans, in some 

 cases extending down to a depth of three feet. These burrow holes have 

 been filled with ferruginous sand and gravel conglomerates that are con- 

 nected directly with the overlying conglomerate. To the northeast, in 

 Twp. 17 S, R. 13 E, where the conglomerate rests upon the upper shale 

 of the Martinez, it contains shale inclusions at the base. 



STRATIGRAPHY 



The stratigraphy in the vicinity of Cantua and Salt Creek 

 * is in a broad way simple; but in detail it is highly complicated (see 

 figure 9 ) . Beds ranging in age from Jurassic-Franciscan to the 

 Pleistocene form a great eastward dipping monocline. The Shasta- 



