Secondary dolomitization as a factor determining the reservoir properties of the Lower Devonian deposits in Eastern edge of the Khoreyver depression (Timan-Pechora basin)

Abstract

The Lower Devonian deposits were characterized in terms of their composition, texture and secondary transformations, the distribution of various types of pore space was analyzed and several types of dolomite textures were identified. The analysis showed that permeability, solubility and primary texture of carbonate rock or sediment, as well as temperature, volume and exposure time of dolomitizing fluids are key factors for dolomitization and depending on these factors dolomitization can lead to not only increase but also decrease of porosity.