ANALYSIS OF SOME TORSION-BALANCE RESULTS 
IN CALIFORNIA! 
ROBERT H. MILLER? 
Beverly Hills, California 
ABSTRACT 
The writer discusses torsion-balance results obtained in the Los Angeles basin. 
It is shown that here the distribution of gravity which is observed in the vicinity of 
an oil field is in no way connected with the inherent density of the beds. One phase 
of the mathematical theory of geophysics dealing with the gravity distribution set up 
by the folding of an otherwise uniformly dense bed is discussed, and it is shown that, 
in the region in question, the distribution of gravity is entirely the result of this folding. 
An approximate method of interpreting gravitational distribution in terms of sub- 
surface structure is described. 
Though the practical value of geophysics as a means of direct as- 
sistance in the solution of geological problems which confront many 
branches of oil exploration is far from being realized by many operators 
in California, this branch of geophysics has made great strides within 
the last few years, and is now equipped to give remarkably satisfactory 
subsurface information. The geological conditions in California are 
admittedly more complex than those of the coastal region of Texas and 
Louisiana, where geophysics was first used in the oil industry in the 
United States, but this complexity does not preclude the possibility of 
good results. After the difficulties have been overcome, more informa- 
tion may be deduced from geophysical studies in this region than in 
regions of simpler geology. The complexity of conditions in California, 
however, makes it necessary to leave the interpretation of the results to 
experts, in the same manner that micropaleontology is,now left in the 
hands of a few men who really understand the work. When this is done 
the old record of geophysics will be erased and a new record established, 
which will encourage companies to spend their money on geophysical 
programs and subsequent leasing and drilling. There continue to exist 
erroneous ideas as to the nature of the properties of materials which are 
used in geophysical determinations, so that when the fundamental theory 
tPresented before the Association at the San Antonio meeting, March 21, 1931. 
Manuscript received, February 12, 1931. 
2Geologist and engineer, 438 South Maple Drive. Introduced by Paul B. 
Whitney. 
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