HR: 1330h
AN: B12A-0749 [PDF]
TI: Integrating Acoustic Imaging of Flow Regimes With Bathymetry: A Case Study, Main Endeavor
Field
AU: * Bemis, K G
EM: bemis@rci.rutgers.edu
AF: Institute of Marine and Coastal Sciences and Department of Geological Sciences, Rutgers University
71 Dudley Rd, New Brunswick, NJ 08901-8521 United States
AU: Rona, P A
EM: rona@imcs.rutgers.edu
AF: Institute of Marine and Coastal Sciences and Department of Geological Sciences, Rutgers University
71 Dudley Rd, New Brunswick, NJ 08901-8521 United States
AU: Jackson, D R
EM: drj@apl.washington.edu
AF: Applied Physics Laboratory, University of Washington, Seattle, WA 98105-6698 United States
AU: Jones, C D
EM: cjones@apl.washington.edu
AF: Applied Physics Laboratory, University of Washington, Seattle, WA 98105-6698 United States
AB:
A unified view of the seafloor and the hydrothermal flow regimes (plumes and diffuse flow) is constructed for three major
vent clusters in the Main Endeavour Field (e.g., Grotto, S\&M, and Salut) of the Endeavour Segment, Juan de Fuca Ridge. The
Main Endeavour Field is one of RIDGE 2000's Integrated Study Sites. A variety of visualization techniques are used to
reconstruct the plumes (3D) and the diffuse flow field (2D) based on our acoustic imaging data set (July 2000 cruise). Plumes
are identified as volumes of high backscatter intensity (indicating high particulate content or sharp density contrasts due
to temperature variations) that remained high intensity when successive acoustic pings were subtracted (indicating that the
acoustic targets producing the backscatter were in motion). Areas of diffuse flow are detected using our acoustic
scintillation technique (AST). For the Grotto vent region (where a new Doppler technique was used to estimate vertical
velocities in the plume), we estimate the areal partitioning between black smoker and diffuse flow in terms of volume fluxes.
The volumetric and areal regions, where plume and diffuse flow were imaged, are registered over the bathymetry and compared
to geologic maps of each region. The resulting images provide a unified view of the seafloor by integrating hydrothermal flow
with geology.
DE: 3035 Midocean ridge processes
DE: 3045 Seafloor morphology and bottom photography
DE: 4259 Ocean acoustics
DE: 8135 Hydrothermal systems (8424)
DE: 8424 Hydrothermal systems (8135)
SC: Biogeosciences [B]
MN: 2003 Fall Meeting