TY - JOUR

T1 - Transformation of terrestrial organic matter during mesocatagenesis and apocatagenesis

AU - Kontorovich, A. E.

AU - Dolzhenko, K. V.

AU - Fomin, A. N.

N1 - Funding Information: The final part of the study was supported by the Russian Foundation for Basic Research (project no. 183500337) and as part of the Basic Research Program (project no. 0331-2019-0022) “Organic Geochemistry and History of Geological Development of Dominant Petroleum Systems in the upper Proterozoic and Phanerozoic of Siberia”. Publisher Copyright: © 2020 Publishing House of Siberian Branch of the Russian Academy of Sciences. All rights reserved. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.

PY - 2020/8

Y1 - 2020/8

N2 - A combination of modern analytical methods was used to study terrestrial organic matter from upper Paleozoic rocks in the central part of the Vulyui hemisyneclise (East Siberia) sampled from the depth interval 3370-6458 m penetrated in the Srednevilyuiskaya-27 superdeep well. In this study, we used 71 core samples to trace depth variations in the geochemical characteristics of organicmatter during middle-late mesocatagenesis and apocatagenesis: organic carbon content (Corg), Rock-Eval pyrolysis parameters (HI, Tmax), carbon isotope composition, thermal maturity (RoVt, %), hydrocarbon type composition (hydrocarbons, resins, and asphaltenes), distributions of n-alkanes (TIC), steranes (m/z 217), and terpanes (m/z 191), and standard biomarker indices with increasing degree of thermal maturity. It is shown that during late mesocatagenesis and apocatagenesis, the pyrolysis parameters and biomarker indicators are no longer effective as indicators of organic-matter maturity and genesis.

AB - A combination of modern analytical methods was used to study terrestrial organic matter from upper Paleozoic rocks in the central part of the Vulyui hemisyneclise (East Siberia) sampled from the depth interval 3370-6458 m penetrated in the Srednevilyuiskaya-27 superdeep well. In this study, we used 71 core samples to trace depth variations in the geochemical characteristics of organicmatter during middle-late mesocatagenesis and apocatagenesis: organic carbon content (Corg), Rock-Eval pyrolysis parameters (HI, Tmax), carbon isotope composition, thermal maturity (RoVt, %), hydrocarbon type composition (hydrocarbons, resins, and asphaltenes), distributions of n-alkanes (TIC), steranes (m/z 217), and terpanes (m/z 191), and standard biomarker indices with increasing degree of thermal maturity. It is shown that during late mesocatagenesis and apocatagenesis, the pyrolysis parameters and biomarker indicators are no longer effective as indicators of organic-matter maturity and genesis.

KW - Biomarker hydrocarbons

KW - Catagenesis

KW - Hydrocarbon type composition

KW - Pyrolysis

KW - Terrestrial organic matter

KW - Upper Paleozoic deposits

KW - Vilyui hemisyneclise

KW - biomarker hydrocarbons

KW - hydrocarbon type composition

KW - terrestrial organic matter

KW - catagenesis

KW - upper Paleozoic deposits

KW - pyrolysis

UR - http://www.scopus.com/inward/record.url?scp=85093835622&partnerID=8YFLogxK

U2 - 10.15372/RGG2020116

DO - 10.15372/RGG2020116

M3 - Article

AN - SCOPUS:85093835622

VL - 61

SP - 891

EP - 905

JO - Russian Geology and Geophysics

JF - Russian Geology and Geophysics

SN - 1068-7971

IS - 8

ER -