Open AccessOrganic geochemistry of the Lower Jurassic Sortehat Formation, Jameson Land, East Greenland
Author(s) -
Helle Krabbe,
Flemming G. Christiansen,
Gregers Dam,
Stefan Piasecki,
Lars Stemmerik
Publication year - 1994
Publication title -
rapport
Language(s) - English
Resource type - Journals
eISSN - 2597-2944
pISSN - 0418-6559
DOI - 10.34194/rapggu.v164.8266
Subject(s) - phytane , hopanoids , sterane , brackish water , geology , biomarker , dominance (genetics) , pristane , organic matter , deposition (geology) , organic geochemistry , palynology , sedimentary depositional environment , paleontology , geochemistry , hydrocarbon , oceanography , source rock , ecology , salinity , chemistry , biology , pollen , biochemistry , organic chemistry , structural basin , sediment , gene
Biomarker analyses of Lower Jurassic shales from the Sortehat Formation, Jameson Land, central East Greenland carried out in combination with palynological studies demonstrate deposition in a fresh to brackish water environment, which became increasingly saline towards the top. The formation is regionally immature to early mature with respect to hydrocarbon generation, and the lowermost 2–20 m have a fair generation potential. Biomarker analysis of the brackish water part shows dominance of C16–C21 n-alkanes, high pristane/phytane ratios, high hopane/sterane ratios, high relative amounts of C29–C31 hopanes and C2717α-trisnorhopane. Steranes are dominated by C29 isomers. The organic matter is composed of bacteria, algae and land plants interpreted from biomarker distributions. The combined data set suggests that deposition took place during an overall rise in relative sea level.