Organic matter at sites 642, 643, and 644, ODP Leg 104

T.J. McDonald; M.C. Kennicutt; J.M. Brooks; Keith A. Kvenvolden

doi:10.2973/odp.proc.sr.104.123.1989

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Organic matter at sites 642, 643, and 644, ODP Leg 104

T.J. McDonald·M.C. Kennicutt·J.M. Brooks·Keith A. Kvenvolden

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Abstract

Sedimentary extractable organic matter was analyzed at three ODP Leg 104 sites in the Norwegian Sea. Organic carbon content ranged from less than 0.1% to a maximum of 1.8%. Extractable organic matter content and unresolved complex mixture concentrations were low and randomly distributed. Low levels of aliphatic (branched and normal) and aromatic hydrocarbons were detected in all of the sediments analyzed. Total aliphatic and aromatic hydrocarbon concentrations ranged from 176 to 3,214 and 6 to 820 ppb, respectively. The concentrations of individual aliphatic (n-C15 to n-C32) and aromatic (two- to five-ring) hydrocarbons were generally less than 50 ppb and less than 10 ppb, respectively. No significant trend with sub-bottom depth was observed in either bulk organic matter or individual hydrocarbon concentrations. The predominant source of Cenozoic sedimentary hydrocarbons is concluded to be ice-rafted debris from the adjacent continent. All sites contain a mixture of recycled, mature petroleum-related and terrestrially derived hydrocarbons.

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Proceedings of the Ocean Drilling Program: Scientific Results Article

Source-reported bounding extent: 63.97596090918338° to 67.95814786101579° latitude; -2.5048828125° to 9.2724609375° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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T.J. McDonald, M.C. Kennicutt, J.M. Brooks, Keith A. Kvenvolden. 1989. Organic matter at sites 642, 643, and 644, ODP Leg 104. https://doi.org/10.2973/odp.proc.sr.104.123.1989

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