HR: 10:50h
AN: OS42A-03    [Abstracts]
TI: Mapping of Hydrothermal Plumes on the Gakkel Ridge During AGAVE 2007
AU: * Edmonds, H N
EM: edmonds@utmsi.utexas.edu
AF: University of Texas at Austin, Marine Science Institute, Port Aransas, TX 78373, United States
AU: Winsor, P
EM: pwinsor@whoi.edu
AF: Woods Hole Oceanographic Instution, 360 Woods Hole Rd., Woods Hole, MA 02543, United States
AU: Nakamura, K
EM: koichi.nakamura@aist.go.jp
AF: National Institute of Advanced Industrial Science and Technology, AIST Tsukuba Central 1-1-1 Higashi, Tsukuba, 305-8567, Japan
AU: Liljebladh, B
EM: beli@gvc.gu.se
AF: Goteborg University, Dept. of Earth Sciences Box 460, Goteborg, 40530, Sweden
AU: Upchurch, L M
EM: upchurch@utmsi.utexas.edu
AF: University of Texas at Austin, Marine Science Institute, Port Aransas, TX 78373, United States
AU: Stranne, C
EM: stranne@gvc.gu.se
AF: Goteborg University, Dept. of Earth Sciences Box 460, Goteborg, 40530, Sweden
AU: Tupper, G
EM: gtupper@whoi.edu
AF: Woods Hole Oceanographic Instution, 360 Woods Hole Rd., Woods Hole, MA 02543, United States
AU: Jakuba, M
EM: jakuba@spray.me.jhu.edu
AF: Johns Hopkins University, Dynamical Systems and Control Lab 3400 North Charles Street, Baltimore, MD 21218, United States
AU: Humphris, S
EM: shumphris@whoi.edu
AF: Woods Hole Oceanographic Instution, 360 Woods Hole Rd., Woods Hole, MA 02543, United States
AU: Shank, T M
EM: tshank@whoi.edu
AF: Woods Hole Oceanographic Instution, 360 Woods Hole Rd., Woods Hole, MA 02543, United States
AU: Singh, H
EM: hsingh@whoi.edu
AF: Woods Hole Oceanographic Instution, 360 Woods Hole Rd., Woods Hole, MA 02543, United States
AU: Reves-Sohn, R A
EM: rsohn@whoi.edu
AF: Woods Hole Oceanographic Instution, 360 Woods Hole Rd., Woods Hole, MA 02543, United States
AB: During the Arctic Gakkel Vents Expedition in July and August, 2007, hydrothermal plumes were located and mapped in two distinct regions of the Gakkel Ridge, using both a CTD-rosette and the AUV PUMA, deployed from the icebreaker Oden and equipped with optical (backscatter and transmission) and redox (Eh) sensors in addition to standard CTD instrumentation. CTD casts were conducted in two modes, standard vertical casts and "drift-yo's", which are analogous to tow-yos but whose speed and direction are determined by the ice drift rather than purposeful movement of the ship. At 7.5 degrees east, two MAPR profiles separated by about 10 km in 2001 showed sharp anomalies in temperature and optical backscatter at about 2800 m water depth. We conducted 16 CTD casts in this region, successfully relocating the plume at 2800 m and finding it to be confined to a narrow (approximately 800 m wide in the across-axis direction), along-axis flow. While the amplitude and smoothness of the temperature and backscatter profiles varied with location indicating relative proximity to the source of the plume, no Eh anomalies were observed nor was a seafloor source located. At the volcanically active 85 degrees E site, a total of 20 CTD casts and drifts, and 3 PUMA dives identified at least 6 different plumes, that can be differentiated based on their depths, spatial variability, and/or the strength and nature of the various signals obtained, but again no seafloor source was localized.
DE: 4207 Arctic and Antarctic oceanography (9310, 9315)
DE: 4832 Hydrothermal systems (0450, 1034, 3017, 3616, 8135, 8424)
DE: 8135 Hydrothermal systems (0450, 1034, 3017, 3616, 4832, 8424)
SC: Ocean Sciences [OS]
MN: 2007 Fall Meeting