428 TUTE | O CLIVATEN OLIN GL OLE O GNA 
ville near the sandstone, but at the base of the hill one-half mile 
distant, in strata which could be traced by continuous outcrop to 
the contact. On the north fork of the Atascadero, three miles 
northwest of this locality, is an Awce//a-bearing stratum folded in 
between the older rocks. About 500 feet north of the vertical 
Knoxville shales is a hill capped with a body of Chico sandstone 
with only slightly inclined bedding planes. This hill lies 
directly in the strike of the shales, and although no contact is 
visible there can be no doubt of an unconformity. 
THE RELATION OF THE SERPENTINE TO THE CHICO-KNOXVILLE 
UNCONFORMITY. 
The absence of the Horsetown beds and the presence of 
numerous large bodies of serpentine favor the supposition of a 
break between the upper and lower divisions of the Cretaceous. 
Serpentine occurs intruding the Knoxville and older rocks at many 
points along the Santa Lucia Range. It seemed probable that 
such was the case on Pine Mountain although no good exposures 
were found. Near the Old Padre mine, west of Santa Margarita, 
the Knoxville shales in contact with the serpentine are consid- 
erably metamorphosed. On the Eagle Ranch a dike of serpen- 
tine has been cut on one of the grades, showing its intrusion in 
the Knoxville shales. The writer has never seen serpentine 
intruded in the Chico in any portion of the Coast Ranges, and all 
indications point to its formation during the interval between the 
deposition of the Knoxville beds and the Chico. In the south- 
ern Coast Ranges at least, the disturbance must have caused an 
elevation of the Knoxville, so that during the period represented 
by the deposition of the Horsetown beds in northern California, 
the former must have been above water and undergoing erosion. 
THE NON-CONFORMITY BETWEEN THE MIOCENE AND THE CHICO- 
TEJON SERIES. 
An examination of geological literature relating to the Coast 
Ranges shows that the Miocene has generally been held to have 
been deposited conformably on the Chico-Tejon series. This 
