GEOLOGICAL SIGNIFICANCE OF SEISMIC REFLECTIONS IN THE SEDIMENTARY COVER OF THE EASTERN PART OF THE ABSHERON-PREBALKHAN RIDGE

Abstract

The Absheron-Prebalkhan tectonic zone, often called as the Absheron-Prebalkhan ridge, is a link between two large oil and gas basins of the world, which differ in the genetic level of the basement, i.e.: the South Caspian (SCB) and the Middle Caspian basins (MCB). The considered area has been completely covered by detailed seismic and gravity surveys over the past decades. The article presents material illustrating the information content of seismic sections in different parts of the region, which are characterized by different seismogeological conditions. As a result of the analysis of the latter, the author specified and determined four seismic horizons: SH-A (Akchagyl), SH-I (tops of RS), SH-II (horizon VIII) and SH-III (lower RS) based on the dynamic expressiveness, length, and resolution of the record. The tracking quality of these horizons is not the same. The identification of seismic intervals, which correspond to structural levels based on objectively determined seismic parameters, such as the configuration and relative position of reflections, their continuity, as well as the amplitude and frequency of seismic waves were the basis for seismic stratigraphic analysis of the wave field. The compiled schematic structural maps show the geological structure of the red-colored strata and Akchagyl deposits and the correlation of the structural plans of the latter clearly. Comparison of complex geological and geophysical materials allows to determine the character of the distribution of lithofacies features of RS deposits.