Geology Reference
In-Depth Information
K, mD
°Be
3,0
1000
500
2
2,5
300
200
100
2,0
50
1,5
30
20
1,0
1
10
1
2
5
0,5
3
10
20
30
40
50
60
70
S
IV
, %
Figure 2.20
South Caspian Depression. Neftyanye Kamni Field, Kali Fm. Pelite fraction
content in rock and rock's permeability vs. ground water salinity. 1
.
Permeability values;
2
.
°Ве values;
1.
K
=
f
(
S
IV
);
2.
°Ве =
f
(
S
IV
).
and reservoir permeability. The combination of the described correla-
tions and associations suggests that the major mechanism in the forma-
tion of the ground water ion-salt composition and salinity in the region's
Pliocene is mixing of waters of different genetic type and salinity. These
are hard high-salinity syndepositional Pliocene waters and foreign, much
lower salinity alkaline waters (Mekhtiyev, Rachinsky and Akhundow, 1966;
Mekhtiyev and Rachinsky, 1967; Mekhtiyev and Rachinsky, 1967; Raaben,
1978; Rachinsky and Muradian, 1983).
Modeling was conducted using mixture calculation methodology
(Ogilvy, 1959 and some others) for checking the dominating role of the
injection of highly alkaline waters into the Pliocene interval. The follow-
ing components were used for mixing: a chlorine-calcium brine from the
Surakhany Fm. in the Peschany Isl. Field syndepositional with the enclos-
ing rocks (salinity 724 mg.-equiv. or 206 g/l, secondary salinity factor
17.9%-equiv.) and the alkaline water of the Lokbatan mud volcano (salin-
ity 35.8 mg.-equiv. or 10.2 g/l) and primary alkalinity factor 59.2%-equiv.
(the model of injected underlying waters). Modeling showed (Rachinsky,
1970) the following. On the one hand, the Pliocene ground waters are
