Different-scale investigations of geological heterogeneity of Bazhenov formation in terms of hydrocarbon potential evaluation

UDK: 622.276.031:550.822.3

DOI: 10.24887/0028-2448-2017-3-8-11

Key words: Bazhenov formation, lithology, hard-to-recover reserves, kerogen, fracturing

Authors: A.V. Postnikov, I.S. Gutman, O.V. Postnikova, K.Yu. Olenova, I.I. Khasanov, A.S. Kuznetsov, G.N. Potemkin (Gubkin Russian State University of Oil and Gas (National Research University), RF, Moscow)

In the article actual different-scale lithological, petrophysical and geochemical investigations of the Bazhenov rocks are considered. The authors stated hierarchy levels of structure model including nano-, micro-, rock layer and zones. New methods of investigation are described, specifically ‘microstructure’ modeling. As a result, it was found that the rocks of Bazhenov formation have two types of kerogen distribution on microstructure level. The first type is characterized by even kerogen distribution as tiny aggregates in mineral intergrain space. In the second type kerogen gathered in restricted aggregates lenticular-layer shape.The main components are silica, clay, carbonate and kerogen. The rock layer consists of these components and it is a base of section zone determination.Section zones are different in texture and contents of rocks included, and in porosity types, reservoir types that give an opportunity for hydrocarbon potential evaluation. The lower zone has intercalation of kerogen-clay and clay-kerogen silicite, the upper part has an interval build of kerogen-clay-carbonate and clay-carbonate-kerogen silicite. In the lower part of middle zone clay-kerogen and kerogen-clay silicite are prevalent, in the upper part of zone interval of kerogen-clay-carbonate and clay-carbonate-kerogen silicite are found. In the upper zone of section kerogen-clay-carbonate and clay-carbonate-kerogen silicite are prevalent.

References

1. Postnikov A.V., Postnikova O.V., Olenova K.Yu. et al., New methodological

aspects of lithological research of rocks Bazhenov formation (In Russ.),

Neftyanoe khozyaystvo = Oil Industry, 2015, no. 10, pp. 23–27.

2. Khasanov I.I., Rock color analysis using digital images of core material

(In Russ.), Geologiya nefti i gaza = The journal Oil and Gas Geology, 2014,

no. 5, pp. 33–39.

3. Gutman I.S., Postnikov A.V., Postnikova O.V. et al., Methodical approach to

vertical zonation of Bazhenov formation in relation to resources evaluation

(In Russ.), Nedropol'zovanie XXI vek, 2016, no. 6, pp. 80–87.