402 H. W. TURNER — GEOLOGY OF MOUNT DIABLO. 



The post-Pliocene beds south of the mouutain are also disturbed, but to 

 a much less extent than the Pliocene beds, dipping toward the south in 

 some places at an angle of 45°, while farther away the dip is less ; and my 

 recollection is that the strata of sand and gravel by the road from Sunol to 

 Livermore are nearly horizontal. When we consider that the Pliocene 

 strata in this vicinity either dip toward the south at a very high angle (75° 

 or more) or are actually reversed and dip toward the north, it would appear 

 that the post-Pliocene deposits lie unconformably on the Pliocene. 



It is probable that by the orographic disturbance attendant on the eleva- 

 tion of the central mountain mass all the strata that lie south of Suisun 

 bay, west of the Sacramento valley, north of Livermore valley, and east of 

 San Ramon valley were more or less affected. 



In speaking of the elevation of the central mass, I do not mean to imply 

 that it was pushed up bodily from below. The force may have been 

 tangential. 



