Vou. III] ANDERSON—NEOCENE DEPOSITS OF KERN RIVER 81 
it requires no special notice here. The older series consists 
of granitic and metamorphic rocks, among which are horn- 
blendic and other crystalline schists, phthanites and limestones. 
The contact between the older series and the Neocene is usually 
well defined, so that the boundaries are easily mapped. 
There are a few isolated areas of Neocene which are evi- 
dently superficial, and also a few unimportant areas of the 
basement rocks exposed by erosion within the boundaries of 
the Neocene. Moreover, the Neocene deposits occupy some 
troughs in the basement rocks which appear to have been 
excavated in pre-Neocene times. The most important of these 
troughs is that of the Caliente canyon which will be described 
hereafter. 
THe NEOCENE SERIES 
The Neocene deposits extend along the foot-hills of the 
Sierra from near White River southward to the Tejon valley, 
forming a zone of varying width, fifty or more miles in length. 
This zone narrows at each end, though more gradually at the 
south, and has its greatest width in the section along Poso 
Creek. 
As a feature of great economic value this area includes the 
well known oil-fields of the Kern River, which are situated 
_ near the mouth of the shallow canyon of the lower Kern River. 
But it is not the design to give prominence to the economic 
features of the geology in this paper. 
STRUCTURE OF THE NEOCENE 
The Neocene deposits of the Kern River area were evidently 
laid down upon a floor of older rocks that had been much 
eroded. This fact is illustrated by the somewhat broken 
boundary, by the isolated areas of granite within the Neocene, 
and by the filling of pre-Neocene troughs by the basal beds of 
the Neocene. This latter feature is particularly well shown in 
the case of the Caliente canyon. To some extent the dip and 
strike of the basal beds conform to these irregularities, but 
this is not usually noticeable. 
In the main, the structure of the Neocene beds is simple, and 
consists of a gentle dip to the southwest, which rarely exceeds 
5° or 6°. The greatest dip is near the base in certain disturbed 
