Organic Matter of Domanik Deposits of the Timan–Pechora Basin: the Oil Window Conditions

Abstract —A comprehensive study of Domanik deposits of the Timan–Pechora Basin has been carried out. The examined composition of hydrocarbon biomarkers, chemical structure of kerogen, carbon isotope composition, and rock lithology, the Rock-Eval pyrolysis data, and the contents of bitumen and Corg in the rocks give an insight into the geochemical processes in the oil window in the Domanik deposits, which took place at Tmax = 435–450 °C. The bitumen coefficient βCB is maximum in this temperature interval, reaching 30%. The obtained data on the distribution of polycyclic biomarkers in the Domanik rocks and the bitumen and Rock-Eval pyrolysis data allowed determining the boundary values of biomarker maturity coefficients in the study of the maturation of organic matter of the rocks. The carbon isotope composition of bitumen fractions in the Domanik rocks is considered, and the bimodal distribution of the δ13C values of the bitumen is shown.

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Climate controls on C3 vs. C4 productivity in North American grasslands from carbon isotope composition of soil organic matter

Global Change Biology ◽

10.1111/j.1365-2486.2008.01552.x ◽

2008 ◽

Vol 14 (5) ◽

pp. 1141-1155 ◽

Cited By ~ 64

Author(s):

JOSEPH C. Von FISCHER ◽

LARRY L. TIESZEN ◽

DAVID S. SCHIMEL

Keyword(s):

Organic Matter ◽

Soil Organic Matter ◽

Carbon Isotope ◽

North American ◽

Isotope Composition ◽

Carbon Isotope Composition ◽

Climate Controls

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Comparison of organic geochemical and palynofacies methods: Example from the Upper Triassic Gassum Formation in Denmark

Bulletin of the Geological Society of Denmark ◽

10.37570/bgsd-1990-38-23 ◽

1991 ◽

Vol 38 ◽

pp. 267-277

Author(s):

Bjørn Buchardt ◽

Marianne Vasard Nielsen

Keyword(s):

Organic Matter ◽

Carbon Isotope ◽

Isotope Composition ◽

Lower Jurassic ◽

Upper Triassic ◽

Carbon Isotope Composition ◽

Preparation Methods ◽

Rock Samples ◽

Deep Well ◽

Amorphous Organic Matter

Copenhagen, February 19th, 1991. Disseminated organic matter from the · Upper Triassic to Lower Jurassic Gassum Formation in the Gassum-1 deep well has been analyzed by palynological and organic geochemical methods. Tue paper compares the effects of the different preparation methods on the organic matter. The kerogen isolation process (demineralisation by HF) is found to cause major changes in the Rock-Eva! parameters, but not in carbon isotope composition of organic matter. Tm.,- and HI-values determined from kerogen concentrates are more consistent with the palynofacies data than those determined from whole rock samples. The differences are ascribed to analytical problems when dealing with low-TOC whole rock samples. Palynofacies data obtained from unfiltered and filtered kerogen concentrates demonstrate a variable loss of amorphous organic matter during filtration ( up to 1()()%). Other palynomorph distributions are not seriously affected by filtration. The loss in amorphous organic matter has no influence on the Rock-Eva! data and carbon isotope composition. Comparison of polynofacies and carbon isotope data identifies three organic matter sources with characteristic isotopic composition.

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