130 
OIL DISTRICTS OF SOUTHERN CALIFORNIA. 
Iii the region of the Santa Fe wells the details of structure for the 
area along the interior valley underlain by the Fernando conglomer¬ 
ate, in which much of the development has taken place, are somewhat 
obscure. In a general wav, however, it is evident that east of the 
western group of Columbia wells (lease No. 2) the strata are deflected 
from their general strike of N. 65°-70° W. to N. 45° W. in the vicinity of 
the southwestern Santa Fe wells, thence bending to S. 70° E. and 
passing onward into the ridge south of Telegraph Canyon. A trace 
of a similar and concentric deflection, with marked local folds, exists 
also in the rocks of the older formation northeast of the Fernando area, 
in the hill slopes north of the Santa Fe village, and the flat to the east. 
The explanation may be that compression took place after faulting, 
affecting the strata in a like manner on both sides of the general frac¬ 
ture. Still, this occurrence may be a coincidence rather than one of 
direct relationship in the movements of the beds. 
Again, the Fernando formation, though of comparatively steep 
southerly dip in the exterior ridges of the field, assumes a much lower 
angle of inclination farther north in the interior valley region, with an 
actual northerly dip, as evidenced by the logs of the wells of the Gra- 
ham-Loftus and Columbia oil companies, near the line of the fault or 
of maximum folds. (See PI. XI, sec. I-J, and PI. XYI.) In other 
words, there is apparently, through at least the western half of Olinda 
alley, an anticline whose axis coincides with that of the valley, trend¬ 
ing about N. 65° W. 
The anticline is clearly traceable in the eastern face of Brea Ridge, 
the axis passing through the southern group of wells of the Columbia 
Oil Company (lease No. 2), or probably a short distance to the south 
of all these wells. Evidences of the fold also appear in the structural 
lines that cross the crest of the ridge diagonally in Union ground, a 
mile west of the Columbia wells (lease No. 2), and in some of the 
gulches that cut the northern face of the ridge in the same vicinity. 
The strikes and dips vary according to the position of the beds in the 
fold. It is possible that the anticline continues westward to the Brea 
Canyon field, being identical with the fold suggested along the line of 
seepages in the bottom of the valley. Some irregularity is displayed 
in the disposition of the strata along the Eastern third of Brea Ridge, 
the Fernando formation being confined to the southern limb of the 
anticline, though crossing to the north of the axis in the region of the 
Columbia wells (lease No. 2), and possibly farther west, in the ridge 
between the forks of Brea Canyon. 
How far to the east the anticline extends is undetermined. It does 
not appear in the Fernando at the point of the ridge between Soquel 
and Telegraph canyons, although the Puente beds here have the oppo¬ 
site or northerly dip and half a mile up Telegraph Canyon show dis¬ 
tinct evidences of a fold. It may be that the anticline continues 
