The Middle Carboniferous section in the area of research includes the deposits of Podolskian, Kashirskskian, Vereiskian formations of the Moscovian and the Bashkirian stages, all of them are characterized as highly promising in terms of future exploration and production. The research is aimed to develop a new framework of lithological and petrophysical criteria for characterization of the main rock types. The workflow includes thorough analysis of the results fr om the extended set of core studies and tests such as lithology and petrographic descriptions, profile measurements on the whole core and detailed investigations of core plugs. The rock types are identified from a representative collection of samples which includes all the stratigraphic units of the Middle Carboniferous with maximum areal coverage of the study area in the north-west of Bashkortostan wh ere this play is proved productive and widespread. Under the scope of the research new approaches to petrographic description of the rock types are defined and the obtained results are used to adjust the available dataset and identify certain features within the known lithotypes which control the formation of the void space within the rock. The inferred textural and structural features of the identified lithotypes are also supported by the results of CT core scanning. Such approach to rock characterization helps to define critical petrophysical properties of the studied rocks as well as to set out criteria for their identification from well logs. The paper presents the findings from the detailed lithological and petrographic study of each target stratigraphic unit in the Middle Carboniferous section and the main criteria for their petrophysical characterization.
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