No Evidence for Enhanced Methane Flux from the Blake Ridge Depression
Charles K. Paull, William Ussler, III, 2009. "No Evidence for Enhanced Methane Flux from the Blake Ridge Depression", Natural Gas Hydrates—Energy Resource Potential and Associated Geologic Hazards, T. Collett, A. Johnson, C. Knapp, R. Boswell
Download citation file:
Piston cores were collected from the floor, flanks, and background sediments associated with the Blake Ridge Depression (BRD) off the east coast of the United States to determine if this area is a gas-venting site. The hypothesis was that if the depression is associated with focused methane flux, authigenic carbonate mineralization, indicative of methane-related diagenesis and/or steeper pore-water sulfate gradients, should occur within the feature. Sulfate gradients are sensitive to elevated pore-water methane concentrations and anaerobic methane oxidation. Compared with surrounding background sediments, neither steep sul-fate gradients nor authigenic carbonates were observed within the cores collected from the interior of the BRD. The hypothesis that the Black Ridge Depression is or has been a site of enhanced methane venting is not supported by these geochemical observations.