Hoehler, Tori M. et al. (2000): Model, stable isotope, and radiotracer characterization of anaerobic methane oxidation in gas hydrate-bearing sediments of the Blake Ridge
Leg/Site/Hole:
Related Expeditions:
ODP 164
Identifier:
ID:
2001-025803
Type:
georefid
ID:
10.2973/odp.proc.sr.164.242.2000
Type:
doi
Creator:
Name:
Hoehler, Tori M.
Affiliation:
University of North Carolina at Chapel Hill, Marine Sciences Department, Chapel Hill, NC, United States
Role:
author
Name:
Borowski, Walter S.
Affiliation:
University of Tokyo, Japan
Role:
author
Name:
Alperin, Marc J.
Affiliation:
Ocean Drilling Program, United States
Role:
author
Name:
Rodriguez, Nancy M.
Affiliation:
U. S. Geological Survey, United States
Role:
author
Name:
Paull, Charles K.
Affiliation:
University of Texas at Arlington, United States
Role:
author
Identification:
Title:
Model, stable isotope, and radiotracer characterization of anaerobic methane oxidation in gas hydrate-bearing sediments of the Blake Ridge
Year:
2000
Source:
In: Paull, Charles K., Matsumoto, Ryo, Wallace, Paul J., Black, Nancy R., Borowski, Walter S., Collett, Timothy S., Damuth, John E., Dickens, Gerald R., Egeberg, Per Kristian, Goodman, Kim, Hesse, Reinhard F., Hiroki, Yoshihisa, Holbrook, W. Steven, Hoskins, Hartley, Ladd, John, Lodolo, Emanuele, Lorenson, Thomas D., Musgrave, Robert J., Naehr, Thomas H., Okada, Hisatake, Pierre, Catherine, Ruppel, Carolyn D., Satoh, Mikio, Thiery, Regis, Watanabe, Yoshio, Wehner, Hermann, Winters, William J., Wood, Warren T., Miller, Christine M. (editor), Reigel, Ruth (editor), Proceedings of the Ocean Drilling Program; volume 164; scientific results; gas hydrate sampling on the Blake Ridge and Carolina Rise; covering Leg 164 of the cruises of the drilling vessel JOIDES Resolution, Halifax, Nova Scotia, to Miami, Florida, sites 991-997, 31 October-19 December 1995
Publisher:
Texas A & M University, Ocean Drilling Program, College Station, TX, United States
Volume:
164
Issue:
Pages:
79-85
Abstract:
Anaerobic methane oxidation (AMO) was characterized in sediment cores from the Blake Ridge collected during Ocean Drilling Program (ODP) Leg 164. Three independent lines of evidence support the occurrence and scale of AMO at Sites 994 and 995. First, concentration depth profiles of methane from Hole 995B exhibit a region of upward concavity suggestive of methane consumption. Diagenetic modeling of the concentration profile indicates a 1.85-m-thick zone of AMO centered at 21.22 mbsf, with a peak rate of 12.4 nM.d (super -1) . Second, subsurface maxima in tracer-based sulfate reduction rates from Holes 994B and 995B were observed at depths that coincide with the model-predicted AMO zone. The subsurface zone of sulfate reduction was 2 m thick and had a depth integrated rate that compared favorably to that of AMO (1.3 vs. 1.1 nmol.cm (super -2) .d (super -1) , respectively). These features suggest close coupling of AMO and sulfate reduction in the Blake Ridge sediments. Third, measured delta (super 13) CH (sub 4) values are lightest at the point of peak model-predicted methane oxidation and become increasingly (super 13) C-enriched with decreasing sediment depth, consistent with kinetic isotope fractionation during bacterially mediated methane oxidation. The isotopic data predict a somewhat (60 cm) shallower maximum depth of methane oxidation than do the model and sulfate reduction data.
Language:
English
Genre:
Serial
Rights:
URL:
Coverage: Geographic coordinates: North:31.4812 West:-75.3245 East:
-75.3118 South:31.4708
Keywords: General geochemistry; aliphatic hydrocarbons; alkanes; anaerobic environment; Atlantic Ocean; bathymetry; Blake-Bahama Outer Ridge; C-13/C-12; carbon; concentration; diagenesis; gas hydrates; hydrocarbons; isotope ratios; isotopes; Leg 164; marine sediments; methane; North Atlantic; Northwest Atlantic; Ocean Drilling Program; ODP Site 994; ODP Site 995; organic compounds; reduction; sediments; stable isotopes;
.