278 The American Geologist. November, i896 
remnants of thefe beds yet remaining indit^ate tliat a part of 
the region was tiien depressed beneath the sea. Basal con- 
glomerates as extensive as those in the (iolden Gate series 
have not been found, although Diller* describes local conglom- 
erates and coarse sandstone at the base of the Knoxville in 
northern California, while the writer has observed the same 
thing at and near the base of the beds of this age in San Lnis 
Obispo county. The distribution of the Knoxville, as well as 
the fact that at n)any points the Chico rests directly on the 
Golden Gate series, is good evidence that the whole of the area 
of the present Coast ranges was not submerged. 
Chico. While a general subsidence through the Shasta- 
Chico period of deposition is shown by Messrs. Diller and 
Stanton for northern California and Oregon, it is quite clear 
that, through the central Coast ranges, at least, a strati- 
graphic break is discernible. In the Chico sandstone predom- 
inates in many places, while in the Knoxville shale is the most 
characteristic. In portions of the southern Coast ranges the 
Chico contains vast beds of conglomerates. In the upper 
portion of the Sisquoc canon, in northern Santa Barbara 
county, granite boulders, sometimes nearly two feet in diam- 
eter, occur in these beds. Along the lower portion of the 
Cuyamas valley cliffs facing the river and rising several hun- 
dred feet are formed largely of conglomerates. Farther north 
the conglomerates rest on the granite of the San Jose range. 
It seems probable that this range extended to the San Emedio 
mountains during the Chico and that the conglomerates were 
formed near a shore line. In central Santa Barbara county 
there is an extensive body of conglomerate hundreds of feet 
thick which appears to form the dividing line between the 
Knoxville and the Chico. Farther north the basal portion of 
the Chico consists of sandstone, which rests unconformably 
on either the Knoxville or the Golden Gate series. Diller has 
noted similar conglomerates at the base of the Chico in north- 
ern California and considers that they may l)e due to topo- 
graphic changes resulting from the intrusion of the perido- 
tites. We have clear evidence then of extensive land areas in 
the Coast ranges during the upper Cretaceous. 
*Bull. Geol. See. Am., vol. v, p. 163. 
