Vout. 111] ANDERSON—NEOCENE DEPOSITS OF KERN RIVER 93 
so characteristic of the Neocene in many parts of the coast 
region and in the Mt. Diablo Range, are almost absent from 
the deposits of the Kern River area. Microscopic organisms 
are not conspicuous in many of the strata examined, though 
in moderate numbers they are visible in many places. 
At Barker’s ranch on the Kern River, just below the beds 
designated as Zone B, there is an exposure of about 200 feet 
of white, chalk-like shale in which diatoms are readily seen 
with a lens, and there are a few other such outcrops north of 
Poso Creek; but there is in this area no body of strata com- 
parable in thickness to the great beds of siliceous shale on the 
opposite side of the valley almost west of the Kern River. 
In place of such material, however, especially in the northern 
part of the area, there is a considerable quantity of white, or 
light-colored, ash, such as will be described in the following 
paragraphs. 
Among the strata that may be especially mentioned are 
beds of a sandy clay-like rock which has been described as 
“fuller’s earth.” A critical examination of these beds and 
of their material has not been attempted, but, from a cursory 
examination of the rock and of the beds, it seems probable 
that the clay-like matter is residuary. The color, fracture, 
gravity, and other physical properties, and the appearance of 
the rock under a good lens, all conform to the characteristics 
of a sandy volcanic ash. It shows a decided ability to resist 
weathering, even after being mined. In color it is a light 
gray, with a faint greenish tinge. 
An analysis of this material from an old “fullers’ earth” 
mine opened on Sec. 14, T. 27 S., R. 28 E., published by the 
California State Mining Bureau,’ gives the following com- 
position: 
Steer SIO) ) oye tes CM tina WA Ae 54.32 
Minami ayy (WAVL SOs Nia eNO Leak 0) 0) 18.88 
ironyoxatden(MesOnyen cull iia vais 6.50 
ethnars: (XG O) En Ay Ie a avs ee eee 1.00 
INMamaesial (MeO) ny Q uN ly fuk en o22 
ass Dryateuaibeia Ay ree) No uk ee 11.86 
Alkaliibyaditterence ss). 0 0. 02.00) aoe 4.21 
L228) 
1 Bull. Cal. State Mng. Bur., No. 38, p. 275. 
