Geology Reference
In-Depth Information
Figure 4.4
South Caspian Depression. Geothermal gradients vs. depth to base of the
Middle Pliocene Productive (Red-Bed) sequence and transition zone of hard water into
alkaline: a. Apsheron Peninsula; fields: 1. Balakhany-Sabunchi-Ramany, 2. Surakhany,
3. Karachukhur, 4. Zykh, 5. Peschany Isl., 6. Binagady, 7. Lokbatan-Puta, 8. Kala;
b. Lower Kura Depression; fields: 1. Kyurovdagh, 2. Karabagly, 3. Khilly, 4. Babazanan,
5. Neftechala, 6. Mishovdagh, 7. Kalmas, 8. Kyursangya; c. Apsheron-Balkhan zone
of highs, fields: 1. Livanov Bank (East), 2. LAM Bank, 3. Zhdanov Bank, 4. Cheleken,
5.Nebitdag, 6. Koturtepe, 7.Barsagelmes I. Г
=
f
(
H
basePT,KT
); II. Г =
f
(
Н
tran.zone
).
decrease at the subcrops by 15-20% compared with the
stationary regime; it is caused by hysteresis of conductive
sediment heating from their deposition tempo.
2. Decrease in the rock density up the section accompanied
by growth in their heat resistance.
3. Effect of heat transfer optimization progressing up the
section, caused by increased temperature gradients on
approaching the surface and its cooling influence.
4. Heat-shielding effect of a thick (up to 3-5 km) clayey
Paleogene-Miocene sequence directly underlying the
PT-KT. It provides, on the one hand, decrease in the
conductive heat transfer intensity up the section and
decrease in total heat coming downward into the con-
tacting intervals of the section. It provides, on the other
hand, the corresponding overheating of the underly-
ing Mesozoic sediments. [Heat-shielding effect dras-
tically increases in the high-porosity water-saturated
undercompacted (or decompacted) clay intervals with
abnormally high pore pressure (AHPP).] Additional
mechanism limiting the intensity of heat transfer up the
section is the endothermal metamorphism process of
smectite in clays; this process goes with some expendi-
ture of depth heat and causes shrinkage of its flow into
the overlying complexes).
