«Geology, geophysics and development of oil and gas fields»

Structural and textural characteristics of anomalous sections of the Bazhenov Formation

UDC: 553.98(571.1): 551.86
DOI: -

Authors:

¹ National University of Oil and Gas "Gubkin University", Moscow, Russia

Keywords: Bazhenov Formation, anomalous sections of the Bazhenov Formation, Western Siberia, oil

Annotation:

In the practice of oil geological works, several types of sections of the Bazhenov Formation of the West Siberian Basin are distinguished: normal and anomalous ones. The normal section of the Bazhenov Formation is understood to be high-carbon deposits of siliceous-clayey-kerogen composition, the thickness of which reaches 40 m. In the anomalous sections of the Bazhenov Formation there occur a significant number of interlayers (up to several meters) of silt-sand rocks with specific textures. In the Bazhenov Formation zones the total thickness of the deposits can reach 100...150 m.

A large number of researches have been devoted to the problem of studying the anomalous section of the Bazhenov Formation. For the first time K.I. Mikulenko and G.B. Ostriy drew attention to the presence of anomalies in the Bazhenov Formation section in 1968. The problem of studying the conditions of these deposits formation was studied by G.S. Yanovich (1981), I.I. Nesterov (1986), F.G. Gurari (1988), A.I. Petrov (1999), I.S. Gutman (2003) and others.

The productivity of deposits in the anomalous sections of the Bazhenov Formation was identified and proven a long time ago, but their genesis and lithological characteristics are studied rather poorly. The Bazhenov Formation zone is characterized by the widespread development of specific textures, associated with breakthroughs, landslides, cracks and introduction of heterogeneous grain flows.

Based on a large set of lithological studies, the specific structural-textural features of the rocks that compose the anomalous sections of the Bazhenov Formation are characterized.

Bibliography:

1. Gatina N.N. Geologicheskoe stroenie i perspektivy neftegazonosnosti zon anomal’nogo razreza bazhenovsko-achimovskikh otlozheniy Shirotnogo Priob’ya: dis. … kand. geol.-mineral. nauk. – M., 2023.

2. Osyka A.V. Geologicheskie modeli stroeniya titon-berrias-valanzhinskikh otlozheniy ("anomal’nykh razrezov bazhenovskoy svity") v svyazi s podgotovkoy netraditsionnykh ob"ektov dlya poiska zalezhey nefti na territorii deyatel’nosti predpriyatiya "Kogalymneftegaz": dis. … kand. geol.-mineral. nauk. – Tyumen’: Tyumen. gos. neftegaz. un-t, 2006.

3. Mizens G.A. Otlozheniya glubokovodnykh basseynov geologicheskogo proshlogo: uchebno-metodich. posobie. – Ekaterinburg, 2005.

4. Mulder T., Alexander J. The physical character of subaqueous sedimentary density flows and their deposits // Sedimentology. – 2001. – Vol. 48(2). – Рр. 269–299.