104 
SANTA MARIA OIL DISTRICT, CALIFORNIA. 
blue and brown shales, largely the latter, interstratified with hard 
“shell” layers, under some of which are accumulations of gas. 
The first oil zone is struck at a depth of 1,200 to 1,800 feet, and 
ranges in thickness from 12 to 75 feet, although in some of the wells 
sands are encountered at intervals for at least 250 feet below the top 
of the first sand. The oil sand is as a rule rather fine grained and is 
accompanied both above and below by shale and rarely by shell. In 
some of the wells the oil zone appears to be practically continuous 
sand for its entire thickness; in others, alternating sand and shale 
layers furnish the oil. 
A second oil zone occurs about 1,200 feet below the first, the entire 
distance between the two being occupied by shale, with a few hard 
“shell” layers. Very little oil occurs at this horizon. 
A third oil zone about 150 feet thick is penetrated 2,100-feet below 
the first, the formation between the second and third zones being prac¬ 
tically all shale. Comparatively little oil was obtained from this zone 
in this part of the field, although it is thought to be the same as the 
one which is so productive in the Graciosa Western Union area only 
half a mile to the west. This may be accounted for by the general 
synclinal position of the eastern group between the Mount Solomon 
and hypothetical Newlove anticlines. 
PRODUCT. 
The oil in the first productive zone has an average gravity of about 
19° Baume and is very dark colored. Gas is associated with the oil, 
but no water has so far been reported from any of the wells. 
The production of the wells in this group ranges from 5 to 154 bar¬ 
rels per day. The yield of some of the wells is fairly constant, show¬ 
ing only a small decrease in average daily output over a considerable 
number of months; in others, however, the yield is fluctuating. 
LOMPOC FIELD. 
LOCATION. 
The developed territory within the Lompoc field, on which the fol¬ 
lowing discussion is based, lies on the flanks of the Purisima Hills be¬ 
tween the Cebada Canyon and Santa Lucia Canyon roads. Within it 
are located the Logan well of the Los Alamos Oil and Development 
Company; the Hill, Wise & Denigan, and Eefson wells of the Union 
Oil Company; and the abandoned wells of the Todos Santos, Coast 
Line, and Barca oil companies. 
STRUCTURE. 
The dominant structural feature of the field is the main anticline 
of the Purisima Hills. From surface evidence the location of the 
