Sequence Stratigraphic and Petrophysical Analysis of PaleogeneNeogene Deposits of the Dagestan Offshore of the Caspian Sea

Abstract

The Dagestan offshore of the Caspian Sea, surrounded on all sides by oil and gas bearing areas, represents an exceptional interest for the exploration of hydrocarbon fields.The applied sequence stratigraphic analysis allows to stratify the Cenozoic section for the resource’s estimation of the Karagan-Chokrak deposits in new prospective offshore areas. The analysis used well data from the onshore and Dagestan offshore, as well as 2D seismic data.Five sequences were identified in the Cenozoic sediments according to the seismic and well data, from bottom to the top: Maikop SQ1, Chokrak SQ2, Sarmatian SQ3, Akchagyl SQ4, and Apsheron SQ5, in each of them regressive and transgressive tracts have been identified. The boundaries of regressive and transgressive tracts in wells were distinguished on the basis of a mathematical model proposed by the authors for the automated geological interpretation of gamma-ray logging. For evaluation the petrophysical properties of the reservoir rocks the volumetric mineralogical model has been created.

Keywords

• sequence stratigraphic analysis
• karaganchokrak deposits
• dagestan offshore of the caspian sea
• volumetric mineralogical model