Hydrocarbon gases in ODP Leg 104 samples ...

Geochemical studies at three ODP Leg 104 sites on the Wring Plateau help define the distribution of hydrocarbon gases in sediment of this prominent feature of the Norwegian continental margin. Low levels of hydrocarbon gas were encountered in sediment of the outer part of the plateau, but sediment o...

Full description

Bibliographic Details
Main Authors: Kvenvolden, Keith A, Golan-Bac, Margaret, McDonald, Thomas J, Pflaum, Ronald C, Brooks, James M
Format: Article in Journal/Newspaper
Language:English
Published: PANGAEA 1989
Subjects:
Online Access:https://dx.doi.org/10.1594/pangaea.736715
https://doi.pangaea.de/10.1594/PANGAEA.736715
Description
Summary:Geochemical studies at three ODP Leg 104 sites on the Wring Plateau help define the distribution of hydrocarbon gases in sediment of this prominent feature of the Norwegian continental margin. Low levels of hydrocarbon gas were encountered in sediment of the outer part of the plateau, but sediment of the inner part of the plateau is very gassy. The molecular composition of inner plateau gases (>99.9% methane) and the carbon isotopic composition of the methane (avg. = -76 per mil relative to the PDB standard) clearly show that the gas is biogenic. Heavier hydrocarbon gases accompany this methane, and their presence is probably a result of both chemical and microbial low-temperature diagenesis. Although these heavier hydrocarbons were not detected in sediment of the outer part of the plateau during shipboard analyses, subsequent shore-based analyses showed that these compounds are present at very low concentrations. Methane in the gassy sediment of the inner part of the plateau may be present as gas ... : Supplement to: Kvenvolden, Keith A; Golan-Bac, Margaret; McDonald, Thomas J; Pflaum, Ronald C; Brooks, James M (1989): Hydrocarbon gases in sediment of the Vøring Plateau, Norwegian Sea. In: Eldholm, O; Thiede, J; Taylor, E; et al. (eds.), Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 104, 319-326 ...