Geologic features of multilayer hydrocarbon fields as basic definition of criteria for additional exploration

Abstract

On example of Dnieper-Donets basin northern edge of multilayer fields, which have long development history, the current structure of hydrocarbon reserves analysis has been carried out. The fact, that these hydrocarbon deposits concentrate significant oil and gas reserves that are not involved in development, has been established. In geological study 14% of current reserves, evaluated only by results of geophysical studies of wells, have uncertain commercial value and so require additional exploration. Hydrocarbon reserves of proven commercial value, in other words confirmed by testing, also have sizeable volume practically not involved in development coming to 38%. Thus, within the bounds of Dnieper-Donets depression northern edge, a significant part of total proven reserves of multilayer fields hydrocarbon deposits, over 50 % of them, are not being developed. That question undoubtedly needs thorough study. According to the analysis of structural-tectonic, lithological, facial, petrophysical factors, development data and the current structure of hydrocarbon reserves geological structural features of multilayer deposits have been established and three key criteria of their additional exploration have been defined. The first is the advisability of additional exploration only of gas reserves with uncertain commercial value. Second - additional exploration of pools with uncertain commercial value together with «commercial» gas reserves, which are practically not involved in development. These criteria are proposed to be applied during gas deposits additional search in Druzhelyubivka, Borysivka, Maksalske, Chkalivka, Vilkhove, Eugenievka, Krujylivka and Yuliivka fields. Third - additional exploration of main deposits, followed by drilling in their underexplored areas.