PUENTE HILLS : BREA CANYON FIELD. 
123 
gested fault line north of the Menges and Brea Canyon oil territory 
there is marked confusion of the strata, and the region is not without 
evidence of a simple overturn adjacent to the line of displacement. 
If this be the case, the line of seepages along the bottom of Brea 
Canyon marks the line of greatest crushing in the Fernando, except 
directly against the fault plane. Whether anticline or overturn, how¬ 
ever, the general conditions bearing on the occurrence of the oil must 
be practically the same. The composition of the Fernando is repeated 
in a constant succession of conglomerates, sandstones, and clays to the 
bottom of the series, and crushing, equal under a fold of either descrip¬ 
tion, must have produced equivalent effects of texture and structure. 
The prime factors in the field are the Puente fault, the crushing 
attendant on its development, and the contact of Fernando and 
Puente beds. 
OIL WELLS. 
The companies operating in the Brea Canyon held are the Brea 
Canyon, the Union, and the Menges. Other companies have drilled 
wells, but thus far without success The wells of the Brea Canyon Oil 
Company occupy a small area on the northern slope of Brea Ridge 
adjacent to the mouth of the canyon, their number being 21. To the 
east, also on the northern slope of the ridge, is the area drilled by the 
Union Oil Company, 32 wells being distributed along the strike of the 
beds for a distance of 1| miles. The Menges Oil Company’s property 
adjoins that of the Brea Canyon Company on the west, lying just 
west of the mouth of Brea Canyon. This company has two wells. 
The wells of the Brea Canyon Oil Company are sunk in the con¬ 
glomerate and sandstone of the Fernando formation, which strike 
N. 70° W. and dip about 50° S., both with considerable regularity. 
The strata cut are exposed, in part at least, in the northern slope of 
Brea Ridge and along the stream bottom, and include the bitumen- 
bearing sandstone referred to on a preceding page. It is impossible, 
however, to affirm that these horizons have furnished even a portion 
of the oil yielded, so at variance are the records of the wells when com¬ 
pared one with another and with surface exposures. It may be that 
owing to the crushing that has taken place adjacent to the fault and 
its possible extension to the region of the wells oil has filtered from the 
beds originally containing it into others until there has been a general 
diffusion of the fluid through the more porous strata along channels 
that for some reason have more readily permitted migration. In 
marked contrast, however, to the fine wells of this company on the 
south side of the canyon are those on the north side, where in strata 
far more disturbed little or no success has been attained. 
The wells of the Brea Canyon Oil Company vary in depth from 600 
to nearly 2,000 feet, in production from 12 to perhaps 1,000 barrels 
per day, in the gravity of their oil from 18° to 26° B. The heavier 
