The Structure of the Abalak Formation in Detail and Patterns of Distribution of Reservoir Rocks

The sweet spot for the search for oil and gas deposits in the Abalak Formation are interlayers and lenses of carbonate rocks, irregularly distributed. These rocks have fissured-cavernous type reservoirs. The paper shows that the lenslike mass are diagenetic calcareous nodules. Detailed lithological and petrographic studies of core samples revealed patterns of distribution of nodules of the section, and to identify them as belonging to the facies type deposits. The main part of the potential reservoir rocks, carbonate nodules confined to the facies F3, developed at the base of the upper part of the Abalak Formation. Facies is represented by alternating clays siliceous dark gray and clays slightly greenish-gray with plate glauconite. The rocks of this facies, in contrast to the lower, free of mica and silt (5%), irregular carbonated and bioturbated. An integrated approach to the consideration of levels spread of potential reservoir rocks can significantly refine geological models of oil fields and methods of further exploration of hydrocarbon deposits in the Abalak Formation.