Geology Reference
In-Depth Information
Figure 1.1
Location map: South Caspian Depression, structure inventory, oil and gas
occurrences and regional tectonics.
1.
Oil, gas and condensate fi elds;
2.
Unexplored
structures;
3.
Structures with negative appraisal results;
4.
Regional faults;
5.
Unpromising areas. Deep-seated faults: I. Derbent-Krasnovodsk; II. North
Apsheron; III. Apsheron-Balkhan; IV. Sangachaly-Ogurchin; V. Mil-Chikishlyar;
VI. Pre-Caucasus Minor;
VII. Elburs; VIII. West Caspian; IX. East Azerbaijan
(Yamshin); X. Shah-Azizbeck; XI. Sefi drud-Karabogaz; XII. Central Caspian;
XIII. Ogurchin-Chikishlyar; XIV. West Turkmen; XV. Aladag-Messerian;
XVI. Ajikabul-Mardakyany;
XVII. Abich Swell.
pre-Jurassic substrate ranges between 7
8 and 28
30 km and the total
−
−
clay content of this sequence is up to 85
90 %. Th e Jurassic thickness is
4 to 7 km, Cretaceous 6 to 8 km, Paleogene-Miocene 3 to 5.5 km and the
Pliocene-Quaternary 3 to 8 km. Th e Mesozoic clastic portion of the sec-
tion is mostly fl ysh, the Paleogene-Miocene part comprises a clay facies of
the typical geosynclinal schliere and the Pliocene-Quaternary section is
mostly molasses.
Th e basin's structure is a complex system of tectonic steps and individ-
ual macro- and micro-blocks. Th e blocks are separated by the intersecting
deep-seated faults varying in size and orientation and are sequentially sub-
siding from the external frameworks of the basin into the internal South
Caspian Depression (see Figure 1.1). Th e sub-longitudinal faults are, west
to east:
Th e West Caspian (VIII
−
−
VIII), East Azerbaijan (Yashmin) (IX
−
IX),
Shah-Azizbeck (X
−
X), Sefi drud-Karabogaz (XI
−
XI), Central Caspian
(XII
−
XII), Ogurchin-Chikishlyar (XIII
−
XIII), West Turkmen (XIV
−
XIV),
Aladag-Messerian (XV
−
XV).