Geochemistry and fluxes of hydrocarbons to the Beaufort Sea shelf: A multivariate comparison of fluvial inputs and coastal erosion of peat using principal components analysis

Journal Article · Tue Jan 01 04:00:00 EST 1991 · Geochimica et Cosmochimica Acta; (USA)

DOI:https://doi.org/10.1016/0016-7037(91)90416-3· OSTI ID:6131504

Yunker, M B; Macdonald, R W; Cretney, W J; McLaughlin, F A ^[1]; Fowler, B R ^[2]; Dallimore, S R ^[3]

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1. Institute of Ocean Sciences, Sidney, British Columbia (Canada)
2. Seakem Oceanography Ltd., Sidney, British Columbia (Canada)
3. Geological Survey of Canada, Ottawa, Ontario (Canada)

The allochthonous inputs of hydrocarbon to the Canadian Beaufort Shelf were studied by applying principal components analysis (PCA) to well-validated and rigorously blank-corrected samples. Incorporation of a wide range of perdeuterated n-alkanes and PAH into the analysis scheme ensured that only reliably quantified variables were used to interpret the hydrocarbon geochemistry. Application of PCA to Mackenzie River samples demonstrated a homogeneous system, from which we infer coupling or equilibrium between the river particulate hydrocarbons and the dissolved fraction. Particulate hydrocarbon flux from the Mackenzie River is by far the most important terrestrially derived source of hydrocarbons to the Beaufort Sea. The Mackenzie River particulates have a distinct n-alkane signature which can be used to identify the riverine influence on the hydrocarbon geochemistry of the Beaufort Sea shelf. Based on one year's data, the flux of total alkanes is 440 {plus minus} 94 tonne/a, and PAH is 49 {plus minus} 8 tonne/a. The particulate flux exceeds the accompanying dissolved hydrocarbon flux by two orders of magnitude and has a strong seasonal cycle: winter contributes less than an estimated 0.6% of total annual flux. Deltaic silt from the western Mackenzie delta and the smaller amounts of detritus from coastal erosion of peat are minor hydrocarbon sources and contribute, in total, less than 10% to the budget for most alkanes. An important exception, with regard to shelf geochemistry, is the significant quantity of peat-derived higher plant n-alkanes.

• OSTI ID: 6131504
• Journal Information: Geochimica et Cosmochimica Acta; (USA), Journal Name: Geochimica et Cosmochimica Acta; (USA) Vol. 55:1; ISSN GCACA; ISSN 0016-7037
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
023000 -- Petroleum-- Properties & Composition
58 GEOSCIENCES
580000 -- Geosciences
ARCTIC OCEAN
BEAUFORT SEA
CHEMISTRY
CONTINENTAL MARGIN
CONTINENTAL SHELF
DEPOSITION
ENERGY SOURCES
FOSSIL FUELS
FUELS
GEOCHEMISTRY
GEOLOGIC DEPOSITS
HYDROCARBONS
MINERAL RESOURCES
ORGANIC COMPOUNDS
ORGANIC MATTER
ORIGIN
PEAT
PETROLEUM
PETROLEUM DEPOSITS
RESOURCES
SEAS
SURFACE WATERS
VARIATIONS