HR: 14:10h
AN: OS42B-03 INVITED     [PDF]
TI: Coordinated Studies of High-Resolution Marine Methane Hydrates
AU: * Gettrust, J F
EM: gettrust@nrlssc.navy.mil
AF: Naval Research Laboratory, Code 7432, Stennis Space Center, MS 39529 United States
AU: Wood, W T
EM: warren.wood@nrlssc.navy.mil
AF: Naval Research Laboratory, Code 7432, Stennis Space Center, MS 39529 United States
AB: High resolution Studies of marine methane hydrates based on Long-Base-Line (LBL) acoustic navigation allow investigators to collocate direct samples (e.g., cores, heatflow, water-samples, etc.) with remote measurements such as conventional and deep-tow seismic data. Examples are presented based on work done on the Cascadia margin off Vancouver Island using the Naval Research Laboratory's DTAGS (Deep-Towed Acoustics/Geophysics system), coring, water samples and direct observations with an ROV. These data were acquired at the "Bullseye" vent using an acoustic bottom transponder constellation to position DTAGS' source and receivers with an accuracy of 1 to 2 meters. (The constellation was also used to co-locate piston cores with the seismic data with the same accuracy.) This site is of particular interest as it brings together, in a relatively small area, processes of hydrate dissociation, generation, fluid flow, and evidence of chemosynthetic communities. These data are used to constrain numerical simulations of perturbation of the gas hydrate stability zone, fluid flow through the sediments and the impact of these processes the dynamics of gas hydrates.
DE: 3025 Marine seismics (0935)
DE: 3210 Modeling
DE: 4825 Geochemistry
SC: Ocean Sciences [OS]
MN: 2003 Fall Meeting