COMPOSITION OF THE OIL-FIELD WATERS. 
81 
Table 12.— Analyses of ground water at different depths in the Coalinga oil field, Cal., 
showing alteration by oil or coal. 
[See fig. 5, p. 79.] 
74 
75 
76 
77 
78 
79 
80 
PROPERTIES OF REACTION IN 
PER CENT. 
i 
Primary salinity. 
59.0 
67.0 
36.2 
63.8 
64.6 
91.2 
21.8 
Secondary salinity. 
36.8 
18.6 
0 
0 
24.0 
0 
0 
Primary alkalinity. 
0 
0 
50.8 
30.8 
0 
6.6 
74:'4 
Secondary alkalinity. 
4.2 
14.4 
13.0 
5.4 
11.4 
2.2 
3.8 
Per cent of rS0 4 in rS0 4 +rCl... 
80.0 
67.0 
27.6 
.6 
80.0 
76.0 
29.4 
Ratio of rC0 3 +rHC0 3 to rS0 4 .. 
.05 
.26 
6.38 
90.5 
.16 
.13 
8.8 
CONSTITUENTS IN PARTS PER 
MILLION. 
Sodium (Na) and potassium 
(K)«. 
804 
933 
717 
2,872 
544 
3,000 
526 
Calcium (Ca). 
303 
193 
27 
75 
124 
28 
13 
Magnesium (Mg). 
112 
121 
40 
44 
82 
19 
2.6 
Iron oxide (Fe 2 0 3 ) and alumina 
(A1 2 0 3 ). 
14 
19 
3 
56 
Trace. 
4.6 
Sulphate (S0 4 ). 
2,181 
1,673 
170 
23 
1,243 
4,421 
74 
Chloride (Cl). 
404 
606 
332 
2,961 
232 
1,040 
130 
Carbonate (C0 3 )f>. 
76 
282 
686 
1,435 
125 
355 
400 
Sulphide (S). 
83 
Silica (Si0 2 ). 
c 54 
c 249 
95 
c 67 
57 
29 
18 
3,948 
4,076 ’ 
2,070 
7,533 
2,407 
8,892 
1,251.2 
Hydrogen sulphide (H"S). 
104 
REACTING VALUES IN PER CENT. 
Alkalies: 
Sodium (rNa) and potas- 
sium (rK)o... 
29.5 
33.5 
43.5 
47.3 
32.3 
48.9 
48.1 
Alkaline earths: 
Calcium (rCa). 
12.7 
7.9 
1.9 
1.4 
8.5 
.5 
1.4 
Magnesium (rMg). 
7.8 
8.2 
* 4.6 
1.3 
9.2 
.6 
.5 
Strong acids: 
Sulphate (rS0 4 ). 
38.3 
28.7 
5.0 
. 2 
' 35.3 
34.6 
3.2 
Chloride (rCl). 
9.6 
14.1 
13.1 
31.7 
9.0 
11.0 
7.7 
Weak acids: 
Carbonate (rC0 3 )b. 
2.1 
7.6 
31.9 
18.1 
5.7 
4.4 
28.1 
finlnhide (rS)_ 
, 
11.0 
ANALYSIS AS REPORTED.d 
Sodium sulphate. 
96. 76 
100. 33 
14.37 
1.90 
70.80 
382.05 
5. 84 
Sodium chloride.. 
38-93 
56.81 
31.99 
286. 00 
22.37 
100. 30 
12.52 
Sort inm narbnna.t,e 
.66 
1.35 
56. 68 
126.00 
27.54 
39.01 
Snriinm snlrihidfl 
11.85 
Pfl.1r.inm Rnmhatfi 
59.08 
10.12 
. 10 
8. 22 
.50 
Calcium carbonate. 
.82 
20. 76 
3.90 
10. 90 
12.13 
4.07 
1.54 
Ma cmA<3inm siilnha.t.ft 
25.42 
28.53 
.21 
23.77 
Trace. 
Mfl.ffnft<?inm rarhonat© 
4.99 
4. 54 
7. 95 
8. 90 
3. 82 
.52 
Trrm nviriA a/nrl alumina 
. 84 
1.13 
. 16 
3.30 
Trace. 
.27 
Silica. 
c3.15 
c 14. 54 
5. 63 
c 3.90 
3.33 
1.70 
1.03 
230. 65 
238.11 
120.99 
440. 90 
140. 62 
519.48 
73.08 
6.09 
a Reported and calculated as sodium but includes potassium. 
b Reported and calculated as carbonate but probably in part bicarbonate, 
c Includes suspended matter. 
d In hypothetic combinations, in grains per U. S. gallon. 
74,75,76,77. Water from different horizons in four wells of the Associated Oil Co.,sec.36,T.20 S.,R.14 E. 
’ These wells are all within 1,200 feet of a central point, and the four waters probably occur in the 
same vertical section. Analyst, Smith, Emery & Co. Authority, Associated Oil Co. 
74. Water well, 996 feet deep. Water chiefly from about 800 feet, or about 1,000 feet above the oil. 
75 . Oil well. Water corroded casing at 1,160 feet, and probably occurs in water sand at about 1,100 feet. 
Top of oil sand 1,542 feet. „ , „ „ 
76. Oil well. Sulphur water from 1,347 feet. Tar sand 1,170 to 1,205; top of oil sand 1,593 feet. 
77 Oil well. “Bottom water” from 1,802 feet. Oil sand 1,712 to 1,778 feet. 
78 79. Standard Oil Co. well Domengine 1, sec. 27, T. 18 S., R. 15 E. No. 78 represents water from 370 
’ feet; No. 79, water from 3,700 feet, at which depth no oil had been encountered. These analyses 
probably represent the normal changes that occur with increasing depth in waters unaltered by 
the oil. Analyst, Standard Oil Co. . . A . 
80. Water from upper coal mine, sec. 26, T. 20 S., R. 14 E. Water issues from point just above the coal 
bed (in Tejon formation) and is probably unaffected by oil. Analyst, Smith, Emery & t o. 
60439°—Bull. 653—17-6 
