COMPOSITION OF THE OIL-FIELD WATERS. 73 
Table 8. —Analyses of brine or connate water altered by action of oil, from oil wells in 
the Coalinga and Midway oil fields, Cal., and of ocean water. 
46 
47 
48 
49 
50 
51 
52 
PROPERTIES OF REACTION IN PER 
CENT. 
Primary salinity. 
96.2 
86.6 
75.9 
83.8 
91.8 
82.0 
78.6 
Secondary salinity. 
.0 
12.2 
22.5 
13.4 
6.6 
17.0 
21.1 
Primary alkalinity. 
0 
0 
0 
0 
0 
0 
0 
Secondary alkalinity. 
3.8 
1.2 
1.6 
2.8 
1.6 
1.0 
.3 
Per cent of rS0 4 in rS0 4 +rCl_ 
Trace. 
0 
.01 
.06 
0 
.01 
9.2 
CONSTITUENTS IN PARTS PER 
MILLION. 
Sodium (Na). 
o4,137 
11,160 
alO,522 
al3,253 
al0,704 
11,011 
10,710 
Potassium (K). 
124 
156 
390 
Calcium (Ca).. 
81 
848 
2,894 
1,089 
284 
1,188 
420 
Magnesium (Mg). 
40 
425 
7.2 
685 
326 
510 
1,300 
Iron oxide (Fe 203 ) and alumina 
(AI 2 O 3 ). 
32 
35 
11 
Sulphate (S0 4 ). 
Trace. 
0 
31 
18 
0 
9 
2,700 
Chloride (Cl). 
6,367 
20,694 
20,955 
23,553 
17,631 
18,750 
19,410 
Carbonate (C0 3 ). 
b 218 
48 
b 293 
b 626 
b 243 
0 
5 70 
Bicarbonate (HCOj). 
359 
280 
Silica (SiOA .... 
49 
102 
18 
65 
12 
123 
10,924 
33,578 
34,755.2 
39,300 
29,200 
31,885 
35,000 
REACTING VALUES IN PER CENT. 
Alkalies: 
Sodium (rNa). 
a 48.1 
43.0 
a 37.95 
o41.9 
a 45.9 
40.6 
38.5 
Potassium (rK). 
.3 
.4 
.8 
Alkaline earths: 
Calcium (rCa). 
1.0 
3.7 
12.00 
4.0 
1.4 
5.3 
1.8 
Magnesium (rMg). 
.9 
3.0 
.05 
4.1 
2.7 
3.7 
8.9 
Strong acids: 
Sulphate (rS0 4 ). 
Trace. 
.0 
.05 
.0 
Trace. 
4.6 
Chloride (rCl). 
48.1 
49.4 
49.15 
48.5 
49.2 
49.5 
45.2 
Weak acids: 
Carbonate (rC0 3 ). 
b 1.9 
.1 
b. 80 
b 1.5 
b. 8 
.0 
b. 2 
Bicarbonate (rHCOa). 
.5 
.5 
ANALYSIS AS REPORTED. C 
Sodium sulphate... 
Trace. 
Sodium chloride. 
605.36 
1,560.10 
i, 954 .36 
1,575.11 
Sodium carbonate. 
7.34 
9.53 
10.90 
Calcium sulphate. 
Trace. 
2.57 
1.47 
Calcium chloride. 
2.98 
434.50 
167. 26 
45.99 
Calcium carbonate. 
9.13 
28.50 
6.95 
Magnesium sulphate.. 
Trace. 
Magnesium chloride. 
4. 24 
1.64 
114. 05 
61.88 
Magnesium carbonate. 
4.37 
37.95 
11.24 
Iron and alumina.. 
1.88 
2.05 
.63 
Silica. 
2. 84 
1.08 
3. 83 
.70 
638.14 
2,030. 44 
2,296.03 
1,705. 82 
a Reported and calculated as sodium but includes potassium. 
b Reported and calculated as carbonate but probably in part bicarbonate. 
c In hypothetic combinations, in grains per U. S. gallon. 
Coalinga field: . 
46. Acorn Oil Co. well 1, sec. 2, T. 20 S., R. 14 E. Flowing water from 1,104 feet (in brown shale), or 
about 1,000 feet below main oil horizon. Temperature, 86 ° F. Analyst, Luckhardt & Co. 
Authority, H. W. Bell. A partial analysis by H. W. Bell of water struck in this well at 2,528 
feet shows about 7,700 parts per million of Cl and 175 parts of CO 3 . This deeper water thus 
probably resembles No. 50 in its properties of reaction. 
Midway field: 
47. Mays Consolidated Oil Co. well 6 , sec. 28, T. 31 S., R. 23 E. Flowing water from 3,000 feet, or a 
few feet beneath the oil sand. Temperature, 125° F. Sampled by G. S. Rogers, September, 
1915. Analyst, S. C. Dinsmore. 
48. Standard Oil Co. well 6 , sec. 22 , T. 31 S., R. 23 E. Water from 2,700 feet, or in oil zone. Analyst, 
Standard Oil Co., September, 1915. 
49. Associated Oil Co. well 2, sec. 32, T. 31 S., R. 23 E. Water from a short distance above 3,100 feet, 
or more than 100 feet above the oil. Analyst, Smith, Emery & Co. Authority, Associated Oil Co. 
50. Associated Oil Co. well Pioneer Midway 7, sec. 30, T. 31 S., R. 23 E. Water probably from 2,840 
to 2,885 feet, or in the oil measures. Analyst, Smith, Emery & Co. Authority, Associated Oil Co. 
51. Honolulu Oil Co. well 6 , sec. 10, T. 32 S., R. 24 E. Water from 2,755 feet, or close to the horizon. 
of the oil. Sampled by Paul Paine. Analyst, S. C. Dinsmore. 
Ocean water: 
52. Interpretation of the mean of 77 analyses by W. Dittmar of sea water collected by the Challenger 
expedition (Challenger Exped. Rept., Physics and chemistry, vol. 1, p. 203, 1884). 
