MDBT estimation ratio for transformation organic matter ratio in Bazhenov Formation of Western Siberia (Tomsk Oblast, Russia)

Scientific and Technical Challenges in the Well Drilling Progress

Goncharov, I.^1 ; Samoilenko, V.^2 ; Oblasov, N.^2 ; Fadeeva, S.^2

Tomsk Polytechnic University, Tomsk

634034, Russia^1

JSC TomskNIPIneft, Tomsk

634027, Russia^2

关键词: Generative potentials;    Hydrocarbon potential;    Maturity parameters;    Regional distribution;    Rock-Eval pyrolysis;    Total Organic Carbon;    Transformation ratio;    Vitrinite reflectance;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/24/1/012040/pdf
DOI  :  10.1088/1755-1315/24/1/012040

来源: IOP

【 摘 要 】

The Bazhenov Formation is the main source rock in the West Siberian Basin, because of high organic-rich Bazhenov black shales, with a total organic carbon (TOC) content of 10-15wt.% generally. Based on Rock-Eval pyrolysis data, the initial generative potential for a significant part of West Siberian Bazhenov Formation organic matter (OM) is from 10 to 60% expended. Most West Siberian oils are in the Bazhenov Formation due to very high oil potential (initial hydrogen index 710mgHC/gTOC) and widespread regional distribution). Vitrinite reflectance (Ro) does not correctly indicate the transformation ratio (TR) of the OM in Bazhenov black shales. However, GC-MS analysis of extracts indicated a good correlation between some molecular maturity and Rock-Eval maturity parameters. Molecular maturity parameters based on naphthalenes and phenanthrenes are not applicable for Bazhenov Formation OM. While the parameters based on 4-methyldibenzothiophene and 1- methyldibenzothiophene ratio (4MDBT/1MDBT) is applicable in estimating the hydrocarbon potential of Bazhenov Formation black shales and, consequently, provides more reliable information about marine OM TR than does Ro. The 4MDBT/1MDBT ratio is more consistent and precise than pyrolysis data. Therefore, it is more applicable in the case of scarcity of core samples throughout the whole formation.