We investigated magnetic susceptibility (MS) variations in hydrocarbon contaminated sediments. Our objective was to determine if MS can be used as an intrinsic bioremediation indicator due to the activity of iron-reducing bacteria. A contaminated and an uncontaminated core were retrieved from a site contaminated with crude oil near Bemidji, Minnesota and subsampled for MS measurements. The contaminated core revealed enriched MS zones within the hydrocarbon smear zone, which is related to iron-reduction coupled to oxidation of hydrocarbon compounds and the vadose zone, which is coincident with a zone of methane depletion suggesting aerobic or anaerobic oxidation of methane is coupled to iron-reduction. The latter has significant implications for methane cycling. We conclude that MS can serve as a proxy for intrinsic bioremediation due to the activity of iron-reducing bacteria iron-reducing bacteria and for the application of geophysics to iron cycling studies.
F. M. Mewafy et al., "Magnetic Susceptibility As a Proxy for Investigating Microbially Mediated Iron Reduction," Geophysical Research Letters, vol. 38, no. 21, American Geophysical Union (AGU), Nov 2011.
The definitive version is available at https://doi.org/10.1029/2011GL049271
Geosciences and Geological and Petroleum Engineering
Keywords and Phrases
Anoxic Sediments; Bacteria; Biodegradation; Bioremediation; Biotechnology; Contamination; Crude Oil; Magnetic Susceptibility; Methane; Organic Compounds; Pollution; Anaerobic Oxidation Of Methanes; Bemidji, Minnesota; Contaminated Sediment; Hydrocarbon Compounds; Iron Reducing Bacteria; Iron Reduction; Methane Depletion; Vadose Zone; Iron; Contaminated Land; Geophysics; Iron-reducing Bacterium; Microbial Activity; Oxidation; Sediment Pollution; Bemidji; Minnesota; United States
International Standard Serial Number (ISSN)
Article - Journal
© 2011 American Geophysical Union (AGU), All rights reserved.