DBPapers
DOI: 10.5593/sgem2017H/15/S06.081

TYPOMORPIC FEATURES OF PYRITE IN THE SEALS OF OIL FIELDS OF TATARSTAN

L.M. Sitdikova, V.G. Izotov, A.V. Vakhin
Thursday 23 November 2017 by Libadmin2017

References: 17th International Multidisciplinary Scientific GeoConference SGEM 2017, www.sgemviennagreen.org, SGEM2017 Vienna GREEN Conference Proceedings, ISBN 978-619-7408-26-3 / ISSN 1314-2704, 27 - 29 November, 2017, Vol. 17, Issue 15, 643-650 pp; DOI: 10.5593/sgem2017H/15/S06.081

ABSTRACT

Seals of oil deposits of Tatarstan (Volga-Ural petroleum province) are a complex geological and geochemical object. The preservation degree of hydrocarbon deposits is determined by the filtration characteristics of the seals. Migration of the identified portions of hydrocarbon compounds through the fluid lead to a violation of lithological-geochemical equilibrium in the seal. The development of pyrite in the seals is connected both with the syndiagenetic processes of sediment transformation and with biomineralogical transformation. Pyrite is a mineral indicator, which can be localized on the migration paths of hydrocarbon fluids. We studied the typomorphic features of pyrite with various forms of isolation (framboids, finely dispersed shot and scattered form). The certain differences in the morphological types of crystals composing the framboids can be observed. According to the study of the core material, the areas of development of the framboid of pyrite are localized in certain areas of the seal. It permits to assume that such zones were the hydrocarbon systems migration paths from oil deposits during their destruction under the influence of geodynamic processes.

Keywords: oil field, seals, stratigraphic complexes, pyrite, typomorphism