HR: 08:50h
AN: OS21C-04 INVITED [Abstracts]
TI: Hydrothermal Activity on the Southern Mid-Atlantic Ridge: Tectonically- and Volcanically-Hosted High
Temperature Venting at 2-7 Degrees S
AU: * German, C R
EM: cgerman@whoi.edu
AF: NOC, European Way, Southampton, SO14 3ZH
United Kingdom
AU: * German, C R
EM: cgerman@whoi.edu
AF: WHOI, Woods Hole Road, Woods Hole, MA 02543
United States
AU: Parson, L M
EM: lmp@noc.soton.ac.uk
AF: NOC, European Way, Southampton, SO14 3ZH
United Kingdom
AU: Murton, B J
EM: bjm@noc.soton.ac.uk
AF: NOC, European Way, Southampton, SO14 3ZH
United Kingdom
AU: Bennett, S A
EM: saroban@noc.soton.ac.uk
AF: NOC, European Way, Southampton, SO14 3ZH
United Kingdom
AU: Connelly, D P
EM: dpc@noc.soton.ac.uk
AF: NOC, European Way, Southampton, SO14 3ZH
United Kingdom
AU: Evans, A J
EM: alje@noc.soton.ac.uk
AF: NOC, European Way, Southampton, SO14 3ZH
United Kingdom
AU: Prien, R D
EM: ralf.prien@io-warnemuende.de
AF: NOC, European Way, Southampton, SO14 3ZH
United Kingdom
AU: Ramirez-Llodra, E Z
EM: ezr@cucafera.cmima.csic.es
AF: NOC, European Way, Southampton, SO14 3ZH
United Kingdom
AU: Shank, T M
EM: tshank@whoi.edu
AF: WHOI, Woods Hole Road, Woods Hole, MA 02543
United States
AU: Yoerger, D R
EM: dyoerger@whoi.edu
AF: WHOI, Woods Hole Road, Woods Hole, MA 02543
United States
AU: Jakuba, M
EM: mjakuba@whoi.edu
AF: WHOI, Woods Hole Road, Woods Hole, MA 02543
United States
AU: Bradley, A M
EM: abradley@whoi.edu
AF: WHOI, Woods Hole Road, Woods Hole, MA 02543
United States
AU: Baker, E T
EM: edward.baker@noaa.gov
AF: NOAA-PMEL, 7600 Sand Point Way NE, Seattle, WA 98115-6349
United States
AU: Nakamura, K
EM: koichi.nakamura@aist.go.jp
AF: National Institute of Advanced Industrial Science & Technology, AIST Tsukuba Central 7
1-1-1 Higashi, Tsukuba Ibaraki, 305-8567
Japan
AB:
We have conducted a systematic investigation for hydrothermal activity along the southern Mid-Atlantic Ridge,
2°30-6°50 S. Our initial approach was to use a combination of multi-beam swath mapping, deep-tow sidescan sonar
imaging and water column plume-detection using MAPRs and CTD-rosette system to locate new sites of hydrothermal activity
immediately south of the Romanche and Chain Fracture zones. We wanted to test whether these geologic features represent a
significant barrier to gene-flow along-axis away from northern MAR vent ecosystems. During the first leg of our research
cruise (RRS Charles Darwin cruise CD169, Feb-Mar 2005) we used this approach to identify two hydrothermally active regions,
one in a non-transform discontinuity near 4°S and the other in a segment centre characterised by very fresh sheet-flows
near 5°S. During Leg 2 we returned to the second of these areas and deployed ABE, WHOI's autonomous underwater vehicle,
in a three-phase strategy to prospect for, locate, and image new hydrothermal fields. During Phase 1 two discrete target
areas were located ca. 1km apart along strike within the segment centre. During Phase 2 these two areas were each mapped in
detail using an SM2000 system while in situ optical back scatter, Eh, temperature, Mn and Fe(II) sensors were used to confirm
the interception of buoyant hydrothermal plumes rising from the seafloor. Finally we redeployed ABE (Phase 3) to collect
photo-mosaics of each of two new vent-areas whilst simultaneously sampling their buoyant plumes by CTD-rosette for TDMn, Fe
and CH4 analyses.
DE: 3017 Hydrothermal systems (0450, 1034, 3616, 4832, 8135, 8424)
DE: 3035 Midocean ridge processes
DE: 4832 Hydrothermal systems (0450, 1034, 3017, 3616, 8135, 8424)
DE: 8135 Hydrothermal systems (0450, 1034, 3017, 3616, 4832, 8424)
DE: 8424 Hydrothermal systems (0450, 1034, 3017, 3616, 4832, 8135)
SC: Ocean Sciences [OS]
MN: Fall Meeting 2005