Pages
Download article

Geochemical characteristics of terrestrial organic matter in the Upper Paleozoic complex of the Vilyui syneclise and some features of its transformation under thermobaric conditions at great depths

K.V. Dolzhenko, A.N. Fomin, V.N. Melenevsky

Original article

DOI https://doi.org/10.18599/grs.2019.4.77-84

77-84
rus.

open access

Under a Creative Commons license

A combination of geochemical methods were used to study organic matter from Permian rocks in the central part of the Vilyui syneclise (East Siberia) penetrated by the Srednevilyuiskaya-27 ultra-deep well in the depth range of 3370-6458 m. This study discusses variations in the pyrolysis indices (HI, Tmax), hydrocarbon type content (hydrocarbons-resins-asphaltenes), vitrinite reflectance (R0vt, %), organic carbon content (Corg), as well as some trends in the saturated and aromatic hydrocarbon compositions of bitumen extracts from the Upper Paleozoic rocks. Below a depth of about 4.5 km (late mesocatagenesis), the hydrocarbon type composition is characterized by a sharp decrease in the content of asphaltenes from < 30 % (at 4.5-5.0 km) to < 15 % (at 5.0-5.5 km), which are not detected at greater depth. In turn, the resins became the dominant constituent (~ 50-70 %), whereas hydrocarbons account for < 20 % at depths down to 5 km and < 40 % at greater depth. These depths are also characterized by a predominance of saturated hydrocarbons over aromatic compounds with a decrease in the relative contents of high molecular weight compounds in both fractions, as indicated by mass chromatograms. The hydrocarbon index (HI) of organic matter decreases to the first tens from the depth of 4.9 km and to the bottomhole (6519 m); the temperature of the maximum hydrocarbon yield (Tmax) varies between 570-580 °C, showing a slightly increasing trend. Our results show that the generative potential of organic matter from the rocks within the studied depth range (4.9-6.5 km) has been exhausted and that the terrestrial organic matter undergoes significant changes under severe temperature and pressure conditions at great depths.

 

terrestrial organic matter, hydrocarbon type composition, pyrolysis, catagenesis, ultra-deep well, Vilyui syneclise, chromatography-mass spectrometry

 

  • Bodunov E.I., Zueva I.N., Kashirtsev V.A., Utkina N.A., Zykova P.D., Andreev I.N., Bochkovskaya A.B., Kozlova V.A. (1990). Transformation of organic matter in Permian and Carboniferous rocks of the Vilyui syneclise at great depths. Oil and gas potential and issues of oil and gas deposits development in Yakutia. Yakutsk: YANTS SO AN SSSR, pp. 58-69. (In Russ.)
  • Dindoin V.M. (1973). EPR spectroscopy and its capabilities in organic geochemistry. Proc. SNIIGGIMS, is. 166, pp. 37-54. (In Russ.)
  • Dobryanskii A.F. (1948). Geochemistry of Oil. Moscow: Gostoptekhizdat, pp. 286-311. (In Russ.).
  • Dobryanskii A.F. (1961). Chemistry of Oil. Leningrad: Gostoptekhizdat, pp. 143-153. (In Russ.)
  • Kashirtsev V.A., Safronov A.F, Izosimova A.N., Chalaya O.N., Zueva I.N., Trushcheleva G.S., Lifshits S.Kh., Karelina O.S. (2009). Geochemistry of oils from the East of the Siberian Platform. Yakutsk: YANTS SO RAN, 180 p. (In Russ.).
  • Golubeva I.I., Grausman V.V., Meyen S.V., Petrova E.K. (1980). Stratigraphic subdivision of Permian gas-bearing deposits in the central part of the Vilyui syneclise. Stratigraphy of oil- and gas-bearing deposits of Yakutia. Yakutsk: YANTS SO AN SSSR, pp. 36-45. (In Russ.)
  • Kashirtsev V.A., Dolzhenko K.V., Fomin A.N., Kontorovich A.E., Shevchenko N.P. (2017). Hydrocarbon composition of bitumen from deeply buried terrestrial organic matter (zone of apocatagenesis). Russian Geology and Geophysics, 58(6), pp. 702-710. https://doi.org/10.1016/j.rgg.2016.03.018
  • Kashirtsev V.A., Fomin A.N., Shevchenko N.P., Dolzhenko K.V. (2016). New monoaromatic steroids in the organic matter of the apocatagenesis zone. Dokl. Earth Sci., 496(4), pp. 815-818. https://doi.org/10.1134/S1028334X16080031
  • Kontorovich A.E., Danilova V.P., Dindoin V.M. (1973). Variations in the chemical composition of humic organic matter and its paramagnetic properties in the catagenesis zone. Dokl. AN SSSR, 209(6), pp. 1431-1434. (In Russ.)
  • Kontorovich A.E., Polyakova I.D., Kolganova M.M., Soboleva E.I. (1988). Transformations of organic matter during meso- and apocatagenesis. Sovetskaya Geologiya, 7, pp. 26-36. (In Russ.)
  • Kontorovich A.E., Trofimuk A.A. (1976). Lithogenesis and petroleum generation. Fossil Fuels. Problems of Geology and Geochemistry of Naphthides and Bituminous Rocks. Vassoyevich N.B. (Ed.). Moscow: Nauka, pp. 19-36. (In Russ.)
  • Melenevsky V.N., Polyakova I.D., Gladkii Yu.G. (1989). Catagenetic transformations of insoluble organic matter from the Vilyui syneclise. Geologiya Nefti i Gaza = Oil and Gas Geology, 8, pp. 37-38. (In Russ.)
  • Neruchev S.G. (1973). A study of the main phase of oil formation. Modern problems of geology and geochemistry of fossil fuels. Khain V.E. (Ed.). Moscow: Nauka, pp. 43-48. (In Russ.)
  • Kontorovich A.E., Grebenyuk V.V., Fradkin G.S., Bakin V.E., Divina T.A., Zoteev A.M., Matveev V.D., Matveev A.I., Mikulenko K.I., Polyakova I.D., Safronov A.F., Soboleva E.I., Khmelevskiy V.B. (1994). Petroleum basins and regions of Siberia: Lena-Vilyui basin. Novosibirsk: SNIIGGiMS, 107 p. (In Russ.)
  • Polyakova I.D., Borukayev G.Ch., Perozio G.N., Sokolova M.F., Borukayev Ch.B. (1995). Oil and gas potential of deeply buried sediments. Dokl. Earth Sci., 2, pp. 236-239. (In Russ.)
  • Tectonics, geodynamics and metallogeny of the territory of the Republic of Sakha (Yakutia). (2001). Parfenov L.M., Kuz’min M.I. (Ed.). Moscow: Nauka, 571 p. (In Russ.)
  • Vassoyevich N.B. (1967). Theory of sedimentary-migration origin of oil. Izv. AN SSSR, Geol. Ser., 11, pp. 137-142. (In Russ.)
  • Vassoyevich N.B. (1972). Source material for oil and gas. The origin of oil and gas and the formation of their accumulations. Moscow: Nedra, pp. 39-70. (In Russ.)
  •  

Kirill V. Dolzhenko
Trofimuk Institute of Petroleum Geology and Geophysics of the Siberian Branch of the Russian Academy of Sciences
3 Ak. Koptyug ave., Novosibirsk, 630090, Russian Federation
E-mail: DolzhenkoKV@ipgg.sbras.ru

Alexander N. Fomin
Trofimuk Institute of Petroleum Geology and Geophysics of the Siberian Branch of the Russian Academy of Sciences
3 Ak. Koptyug ave., Novosibirsk, 630090, Russian Federation

Vasily N. Melenevsky
Trofimuk Institute of Petroleum Geology and Geophysics of the Siberian Branch of the Russian Academy of Sciences
3 Ak. Koptyug ave., Novosibirsk, 630090, Russian Federation

 

For citation:

Dolzhenko K.V., Fomin A.N., Melenevsky V.N. (2019). Geochemical characteristics of terrestrial organic matter in the Upper Paleozoic complex of the Vilyui syneclise and some features of its transformation under thermobaric conditions at great depths. Georesursy = Georesources, 21(4), pp. 77-84 . DOI: https://doi.org/10.18599/grs.2019.4.77-84