378 University of California Publications in Geology [ VoL - 13 



west of Lion Canon it is clearly a fault (fig. 7), but at the mouth of 

 Deep Canon it is depositional, the fanglomerate overlying the sand- 

 stone and shale. On the north the sediments are faulted against the 

 old schists and the nearly vertical contact can be seen in nearly every 

 small canon which cuts across it. 



The total thickness of the Hathaway formation is unknown, but 

 in the small canon just west of San Gorgonio River 1800 feet of sand- 

 stone and 800 feet of shale are exposed dipping to the north, the sand- 

 stone at 45° and the shale at 15° to 45 degrees. Neither the top nor 

 bottom of the series could be seen, and these figures therefore represent 

 a minimum estimate of the whole. 



Schist == 



,//. ■ ,/k 



Hathaway 

 Sandstone 



Cabezon Fanglomerate 



tl 1 1 



Fig. 7. Section of ridge yrest of Lion Cafion looking east. Scale 1" = 2000'. 



The Lion sandstone, which, if correlated with the beds at Carrizo 

 Creek, "is not older than lower Pliocene," projects up through the 

 Hathaway, apparently dipping beneath, but the contact is rather 

 obscure and there is a bare possibility of it being a fault. Even so, 

 the Lion sandstone would be likely to be faulted from beneath, as it 

 is not exposed anywhere else in the region, and if it were the younger, 

 we would certainly expect to meet with it elsewhere. Then if the 

 Hathaway formation is younger than the Lion sandstone, it must be 

 younger than lower Pliocene. It can hardly be upper Quaternary 

 because of the evidence of time since its deposition : extrusion of basalt, 

 uplift with development of different erosion surfaces, and deposition 

 of great masses of fanglomerate. Hence the conclusion that it is either 

 upper Pliocene or lower Quaternary. 



Santa Ana sandstone. — The low topography along the Santa Ana 

 River is carved from a fanglomerate beneath which lies a sand- 

 stone and shale formation. Near Seven Oaks, sandstone predominates 

 in the sandstone-shale member. For the most part it is medium grey 

 in color, although brown and reddish streaks are present. It also 

 includes strata of coarse granitic detritus up to five and six feet in 

 thickness between which are finely laminated shales and occasional 

 calcareous seams. Compared to the sandstone along the south front 



