Publishing House SB RAS:

Publishing House SB RAS:

Address of the Publishing House SB RAS:
Morskoy pr. 2, 630090 Novosibirsk, Russia



Advanced Search

Russian Geology and Geophysics

2001 year, number 11-12

Catagenetic zoning and petroleum potential of the sedimentary cover of the Barents Sea shelf

S. Gramberg, N. K. Evdokimova, and O. I. Suprunenko
Keywords: Catagenetic zoning, modeling, prediction, vitrinite, reflectance, Barents Sea megatrough, petroleum potential
Pages: 1808-1820

Abstract

The maturity of organic matter (OM) has been investigated according to vitrinite reflectance (Ro). This index has been modeled within the sedimentary cover. The depth dependence of Ro has been studied for the first time in the region. Model curves of OM maturation have been constructed for prospecting and test boreholes. This allows prediction of Ro at depths of to 10-12 km. Maps of OM maturity have been compiled for three OM-rich sequences: Carboniferous-Permian terrigenous-carbonate, Upper Triassic and Upper Jurassic terrigenous. The degree of OM conversion varies from protocatagenesis (PC) in the Cretaceous and Upper Jurassic deposits to apocatagenesis (AC) in the Permian ones. Structural and catagenetic levels are conformable in depressions, whereas mismatches of structural and catagenetic surfaces are observed in the terrigenous-carbonate complex and Lower-Middle Triassic deposits on uplifts, particularly, on the western flank of the Barents Sea megatrough and, to a lesser extent, on the Admiralteiskii megarampart.
The catagenetic model suggests a large-scale hydrocarbon generation in the sedimentary deposits of the deep-seated Barents Sea megatrough from Early Paleozoic to Late Mesozoic. During the last 250 Ma, the greatest petroleum catchment area has occurred in the zone of uplifts on the western flank of the Barents Sea megatrough. The potential of this area is comparable with that of the structures of the Shtokman-Lunin megasaddle, proven by exploration drilling.