56 
OIL-FIELD WATERS IN SAN JOAQUIN VALLEY, CAL. 
radicle. The concentration ranges between 314 parts per million and 
8,790 parts. 
The water of Los Gatos and Diaz creeks in the Coalinga field 
(analyses 1 and 2) is the drainage of a district in which igneous and 
metamorphic as well as sedimentary rocks outcrop. These waters 
differ from the other surface types in their higher content of alkalies 
and in the marked predominance of the magnesium value over that 
of calcium. Crocker Spring (analysis 4) in the Midway field is in¬ 
teresting as the most extreme secondary saline type encountered, the 
predominating dissolved salt being gypsum. (See fig. 4.) Bitter- 
water Creek (No. 5) is characterized by high sulphate and by an 
extremely large amount of dissolved solids, greater than that carried 
by many of the deeper waters. The Kern County Land Co. Spring 
(analysis 6), on the other hand, is characterized by a lower proportion 
of dissolved solids than any of the other waters of the west side, 
which may be due to the fact that it issues near a fault between 
granite and sedimentary rocks. Chiefly because of its low concen¬ 
tration it is characterized by a much higher proportion of secondary 
alkalinity than any of the others. 
Analysis 83 (Table 14, p. 85) shows the average composition of 
Kern River on the east side of San Joaquin Valley. As this water is 
the drainage of a region underlain by granites and other resistant 
rocks it is characterized by primary alkalinity rather than secondary 
salinity, and contains a relatively low proportion of sulphate. It is 
a very dilute solution dominantly secondary alkaline in character. 
