PHYSICAL AND CHEMICAL PROPERTIES OF SOUTH¬ 
ERN CALIFORNIA OILS. 
Compiled by Ralph Arnold. 
INTRODUCTION. 
The United States Geological Survey has done very little in deter¬ 
mining the properties and composition of the California oils, and the 
information here given is compiled from published reports or the 
work of private individuals. By far the greater part of the analyses 
were made by members of the scientific staff of the California State 
Mining Bureau and are published in bulletins Nos. 3, 11, 19, 31, and 
32 of that bureau. The writer is largely indebted for data to Messrs. 
W. L. Watts, Frederick Salat he, H. N. Cooper, and Paul W. Prutz- 
man. (See bibliography for list of papers, etc.) 
GENERAL CHARACTER OF THE SOUTHERN CALIFORNIA 
OILS. 
GRAVITY. 
The gravity of the oil from the wells in the Santa Clara Valley, Los 
Angeles, and Puente Hills districts varies from 10° to over 50° B. 
The heaviest oils are found in the Los Angeles field; the lightest oil 
is that from the unique wells in the gneiss of Placenta Canyon, east 
of Newhall. Certain wells in the Miocene shale of the Puente and 
Olinda fields (Puente Hills district) and the fields south of Sulphur 
and San Cayetano mountains (Santa Clara Valley district) yield oil 
of 30° to 35° gravity, while that in some of the wells in the Pico field 
(Santa Clara Valley district) is said to go as high as 40°. The greater 
part of the production from southern California, however, is oil vary¬ 
ing from 18° to 24°. 
COLOR. 
The crude oils from these districts are mostly black or brownish in 
color. The exceptions are the white oil of the Placenta Canyon wells, 
Santa Clara Valley district, and the greenish, light-gravity oils of the 
Sulphur Mountain and Pico Canyon fields, Santa Clara Valley dis¬ 
trict, and the Puente and Olinda fields, Puente Hills district. Green¬ 
ish oil is also reported in one or two other instances. 
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