Geology, geography and global energy

Scientific and Technical Journal

Peculiarities of structural and geomorphological structure of the north-western part of the Caspian depression on the basis of small-and large-scale interpretation

2013. №3, pp. 33-46

Navrotskiy Oleg K.  - D.Sc. in Geology and Mineralogy, Lower Volga Research Institute of Geology and Geophysics, 70 Moskovskaya st., Saratov, Russia, 410012,,

Zotov Aleksey N.  - Chief Geologist, LLC "LukBelOyl", 42 Ulyanovskaya st., Saratov, Russia, 410056,,

Bondarenko Valentina V.  - Geologist, Lower Volga Research Institute of Geology and Geophysics, 70 Moskovskaya st., Saratov, Russia, 410012,,

The article contains results of structural and morphological analysis and landscape display obtained in the course of interpretation of photographic materials and high-altitude aerial photographs of different scale on the territory of the North-Western part of the Caspian depression. Three sub-types of landscape are mostly developed within the studied area; they are: ravine-beam relief, terrace complex of floodplain terraces of the Volga River, and inundable estuaries. The highest watersheds have absolute marks of 76-100 m, the medium ones are characterized by marks of 61-75 m, and the lowest ones are located at the level of 35-60 m. Complex of floodplain terraces of the Volga River is quite a narrow strip along the left bank of the Volgograd reservoir, which width ranges from several dozens of meters to several kilometers. Broad-area inundable estuaries are allocated in the Southern part of the territory under study. Abundance of the elements of landscape indicating the neotectonic activity draws the attention. Two regional faults crossing the Volga River in the latitudinal direction, nodes crossing lineaments systems of different directions, rectangular bends of erosion cuttings are allocated on the territory under study. During oil and gas reconnaissance it is necessary to take into account the influence of the fault and neotectonics on the formation of oil and gas accumulations: either as a kind of a «pump» that pums the fluids from surrounding areas to the zones of high jointing, or as areas of relaxation of stresses, where mechanical energy is converted into heat, which provides low-temperature conversion of organic matter to hydrocarbons. However, this approach requires further investigation. For successful search for hydrocarbon accumulations it is recommended to combine seismic survey and near-surface gas survey methods.

Key words: interpretation,structural and morphological analysis,landscape display,ravine-beam relief,terrace complex,inundable estuaries,lineaments,neotectonics,faults,oil and gas accumulations