62 
OIL-FIELD WATERS IN SAN JOAQUIN VALLEY, CAL. 
as already explained (p. 46), the presence of small amounts of oil or 
gas in this formation may lead to the development of a modified type 
of water some distance stratigraphically below the oil measures. 
Table 3. —Analyses of normal ground water (“top water ’ ’) from oil wells in the Coalinga 
oil field, Cal. 
15 
16 
17 
18 
19 
20 
21 
PROPERTIES OF REACTION IN PER CENT. 
Primary salinity. 
74.2 
85.4 
82.4 
82.4 
11 
66 
35.6 
Secondary salinity. 
14.6 
6.6 
0 
9.4 
51 
30 
39.0 
Primary alkalinity. 
0 
0 
12.0 
0 
0 
0 
0 
Secondary alkalinity. 
11.2 
8.0 
5.6 
8.2 
38 
4 
25.4 
Per cent of rS0 4 in rS0 4 +rCl. 
86.9 
95.0 
95.4 
95.0 
38.7 
70 
78.5 
Ratio of rC0 3 +rHC0 3 to rS0 4 . 
.15 
.09 
.22 
.09 
1.58 
.06 
.43 
CONSTITUENTS IN PARTS PER MILLION. 
Sodium (Na)o and potassium (K).... 
596 
1,111 
1,760 
3,285 
40 
641 
521 
Calcium (Ca). 
163 
83 
22 
385 
105 
209 
265 
Magnesium (Mg). 
9 
51 
42 
142 
107 
47 
336 
Iron oxide (Fe 2 0 3 ) and alumina (A1 2 0 3 ) 
102 
27 
62 
1 
6 
0 
Sulphate (S0 4 ). 
1,276 
2,376 
3,058 
7,264 
185 
1,365 
1,789 
Chloride (Cl). 
140 
91 
109 
296 
212 
427 
360 
Carbonate (C0 3 ). 
t> 117 
b 135 
b 427 
b 419 
0 
b 49 
b 484 
Bicarbonate (HC0 3 ). 
364 
Silica (Si0 2 ). 
3 
441 
6.7 
49 
• 
29 
7 
40 
2,406 
4,315 
5,486.7 
11,841 
857 
2,751 
3,795 
Hydrogen sulphide (H 2 S). 
14 
.0 
Present. 
.0 
Present. 
REACTING VALUES, IN PER CENT. 
Alkalies: 
Sodium (rNa)a. 
37.1 
42.7 
47.2 
'41.2 
/ 33.0 
17.8 
Potassium (rK). 
> 5.5 
\ 
Alkaline earths: 
Calcium (rCa). 
11.8 
3.6 
.7 
5.5 
16.5 
12.4 
10.5 
Magnesium (rMg). 
1.1 
3.7 
2.1 
3.3 
28 
4.6 
21.7 
Strong acids: 
Sulphate (rS0 4 ). 
38.6 
43.7 
39.3 
43.5 
12 
33.7 
29.3 
Chloride (rCl). 
5.8 
2.3 
1.9 
2.4 
19 
14.3 
8.0 
Weak acids: •" 
Carbonate (rC0 3 ). 
b 5.6 
b 4.0 
b 8.8 
b 4.1 
0 
b 2.0 
b 12. ' 
Bicarbonate (rHC0 3 ). 
19 
ANALYSIS AS REPORTED. C 
Sodium sulphate. 
88.82 
187. 46 
258 46 
557 32 
65 54 
42 05 
Sodium chloride. 
13.47 
8 75 
10 49 
28.57 
41.18 
34 72 
Sodium carbonate. 
.46 
1.55 
34.33 
7 16 
Calcium sulphate. 
20.19 
7.42 
28 33 
41.41 
10 40 
Calcium carbonate. 
8.96 
6.63 
3.23 
35.39 
31 09 
Magnesium sulphate. 
.35 
8.64 
4 98 
34 66 
7 83 
86 12 
Magnesium carbonate. 
1.65 
4. 29 
5 05 
4 56 
4 06 
7 82 
Iron oxide and alumina. 
5.97 
1 59 
3 64 
06 
35 
on 
Silica. 
.19 
25. 78 
.39 
2.86 
.38 
2.34 
140.06 
252.11 
320.57 
691. 75 
160. 75 
221. 70 
Hydrogen sulphide. 
.82 
.00 
Present. 
.00 
Present. 
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. 
15. California Oilfields (Ltd.) well 2, sec. 10, T. 19 S., R. 15 E. Analyst, Smith, Emery & Co., October, 
1915. Authority, California Oilfields (Ltd.). ’ ’ 
16. California Oilfields (Ltd.) well 16, sec. 14, T. 19 S., R. 15 E. Analyst, Smith, Emery & Co., Sep¬ 
tember, 1915. Authority, California Oilfields (Ltd.). 
17. Record Oil Co. well 5, sec. 22, T. 19 S., R. 15 E. Water from above oil zone. Analyst, Smith 
Emery & Co., October, 1915. 
18. Premier Oil Co. well 3, sec. 24, T. 20 S., R. 14 E. Black sulphur water from about 700 feet, or 
about 400 feet above the oil. Analyst, Schalk Chemical Co. Authority, Premier Oil Co. 
19. Kern Trading & Oil Co. well in sec. 13, T. 20 S., R. 14 E. Sampled by G. S. Rogers, October, 
1915. Analyst, S. C. Dmsmore. b ’ * 
20. Nevada Petroleum Co. well 3, sec. 30, T. 20 S., R. 15 E. Flowing water from about 2,100 feet, or 
about 500 feet above the oil. Analyst, Dodge Manfacturing Co., March, 1911. Authority, Nevada 
Petroleum Co. 
21. Ozark Oil Co. well 3, sec. 26, T. 20 S., R. 14 E. Sulphur water from 304 feet, or about 350 feet 
above oil. Analyst, Smith, Emery & Co., January, 1912. Authority, Ozark Oil Co. 
