114 
OIL DISTRICTS OF SOUTHERN CALIFORNIA. 
from the break, the width of the productive zone as at present devel¬ 
oped varying from an eighth to a quarter of a mile. The sandy 
members of the formation, rather than those of clayey consistency, 
yield the petroleum, although in some instances the material is com¬ 
paratively fine, while in others it is coarse and even conglomeratic. 
The gravity of the oil varies from 16° to 23° B., the higher grade 
being reported from greater depths, although, perhaps, from younger 
beds. It is to be remarked also that some of the shallow wells are 
the older and that their condition is now far from satisfactory, water 
having in many instances found its way into oil-bearing strata, with 
the consequent effects of oxygenation and the transmission of more 
or less impurities. The daily production of the wells is said to vary 
from 2 barrels in the oldest to 300 in the newest and deepest. 
Among other groups of wells within what may be regarded as the 
confines of the Whittier field are the Chandler, a group of four wells 
1 mile southeast of the Murphy and Central wells. These were about 
the first drilled in the Whittier field, but are now abandoned. Their 
location was probably determined by an oil seepage from the sand¬ 
stone and conglomerate. They were, however, primitive in equip¬ 
ment and shallow and afforded but a light yield of heav}^ oil. At 
this point the Fernando formation lies in an anticline secondary and 
parallel to the main fold in the hills. The beds south of the axis 
dip from 45° to 70°, and those north of the axis, with steeper dip, 
apparently abut against the Puente fault, being in contact with the 
Puente shale forming the central and higher portion of the hills. 
This shale also pitches to the north immediately adjacent to the 
fracture, a position that may be either normal or overturned, the 
latter occurring at many places within the zone of severe crumpling 
along the southern face of the Puente Hills. The Chandler wells are 
located a little south of the axis of the secondarv anticline referred 
c/ 
to above. 
One or two wells have also been drilled in the same s;eneral region 
as the Chandler group, but in the Puente shale north of the fracture. 
As in the case of other wells in this formation in the territory adja¬ 
cent to the Whittier field, the results were negative. The fact, how¬ 
ever, that the Puente shales or their included sandstone locally carry 
oil is evident from the field developed by the Puente Oil Company, 
but no law governing this relationship has been discovered. In case 
the oil is not originally contained in the formation, its presence is 
probably due to the porportion of sandy members—a factor widely 
variable from point to point. 
At the summit of the Puente Hills, about 1^ miles north of Whittier, 
near the east edge of sec. 16, T. 2 S., P. 11 W., the North Whittier 
Oil Company has drilled two wells on the north limb of the main 
