+--------------------------------------------------------------------------+ | ATLANTIS CRUISE SYNOPSIS | +--------------------------------------------------------------------------+ Voyage - Leg: AT 15-26 Voyage Dates: 13 Nov - 03 Dec, 2007 Chief Scientist(s): Lauren Mullineaux (Mullineaux) Address: WHOI MS 34 Woods Hole Oceanographic Institution Woods Hole MA 02543 Phone: 508 289-2898 Email: lmullineaux @whoi.edu Cruise Objective: This is the third of three cruises of the LADDER project, which aims to address the following questions (see [1]http://www.ldeo.columbia.edu/~ant/LADDER for details): Bio-1) What are the influences of advection and eddy diffusion on the maximal dispersal distance of vent species with given larval life spans? Bio-2) What are the effects of ontogenetic changes in larval behavior (i.e., vertical positioning) on species' dispersal distances? Bio-3) How are the probabilities that larvae will be lost from the ridge system influenced by topography and flow? Might the axial summit trough inhibit off-axis transport of larvae, and serve as a conduit between habitable vent sites? PO-1) What are the mean and temporally varying flows in the vicinity of a mid-ocean ridge crest, and what is their spatial structure and coherence? PO-2) What is the magnitude of the diapycnal diffusivity near the ridge crest? PO-3) How rapid is lateral dispersion, and how effective is lateral homogenization by eddy diffusion near the ridge crest? Science Activities: An observational program will be carried out on the crest of the East Pacific Rise near 9:50N. The main activities are: 1) Recovery of Mooring Array. Seven moorings equipped with 15 current meters, 2 velocity profilers and 3 sediment traps will be recovered from a cross-shaped array centered on the EPR crest at 9:30N. Three axial moorings were positioned within the axial trough between 9:10 and 9:50N; a cross-axial mooring line was deployed at 9:30N between 103:55 and 104:35W. The moorings collected data between 2000 and 2900m. 2) CTD/LADCP profiling. An extensive survey will be carried out at night, and occasionally during daytime, both along the EPR axis and on the flanks. 3) Microstructure profiling. A survey using a deep microstructure profiling system (DMP) will be coordinated with the CTD/LADCP deployments, to be carried out at night, and occasionally during daytime, along the EPR axis and on the flanks. 4) Recover larval sediment trap moorings. Two short moorings with sediment traps will be recovered from a site near 9-50 (TrapL1, S of Ty/Io vent, near NA) and near 9-30 (TrapL2, near CA). These were used to monitor temporal variation in larval supply to the vent sites. 5) Deploy and recover plankton-pump moorings. Pairs of moorings will be deployed along the ridge axis, with one near and the other away from an active vent community. Each mooring will support two plankton pumps, one near-bottom (4 mab) and the other at the level of the neutrally-buoyant plume. Four sets of pairs will be deployed over the course of the cruise, each for a ~2-day interval. The samples will be used to quantify larval abundances with respect to potential barriers to dispersal (e.g., the axial summit trough walls, or lateral offsets in the ASCT) and distance from potential source populations. 6) Monitor colonization on the seafloor. Colonization experiments will be conducted with basalt blocks and plastic sandwiches placed on the seafloor at active vent sites. We will recover experiments from Dec. 2006 and set out new ones. Our main focus will be on the diffuse-flow communities. 7) Characterization of established and new vent communities via video imagery. This is a continuation of the Beaulieu and Rhzanov project. In addition to LADDER, time will be devoted to the following projects: Hydrothermal vent meiobenthos (PI: Bright): The aim of this project is to study the present status of the meiobenthic community shortly past eruption and to follow the succession of colonization and development of communities. Cruise activities include collection of meiofauna from different natural substrates, from the water column at various heights above the bottom, and from off-axis sediments. Additionally, meiofauna settlement devices will be deployed and recovered. Geochemistry of hydrothermal particulates (PI: Breier): collection of 36 samples of particles in a system during 4-5 hours of wire-time as part of a CTD-rosette cast. Water column denitrification (PI: Schwartz) Collection of water column samples for analysis of N2/Ar ratios and dissolved nutrients to assess water column denitrification rates in the study region. Analysis of water samples from the vent field to provide an interesting assessment of the relative influence of N cycling in these regions versus the overlying water column. Operations Area: EPR 9:50N (Ridge2000 EPR ISS site) 104:15W, 9-10N 2500-3000m Departure Port: Manzanillo, Mexico Agent: Primary Agent: Vasile Tudoran Transport 819 Ohio Ave. Long Beach, CA 90804 Contact: Vasile Tudoran Phone: (562) 882-5590 Fax: (562) 434-9800 Email : [2]vtudoran@aol.com Subagent: Master R/V Atlantis Attn: Scientist's Name IN TRANSIT MANZANILLO MEXICO c/o Continental Maritime SA 83 Calle Colhuas, Centro 28200 Manzanillo, Colima MEXICO Contact: Daniel Arias Romo Phone/Fax: 011 52 314 33 21223 Cell: 011 52 314 100 8862 Email: [3]danielromo2003@yahoo.com.mx Arrival Port: Manzanillo, Mexico Agent: Same as above SHIP Installed or Normally 12 kHz Transducer Carried Equipment: Relay Transponder for wire use ADCP - 75 kHz Deionized Waahter Syste CTD/Rosette - 23 X10L - all standard CTD Sensors, LADCP, light-scattering sensor, Tubidity Sensor (JD 8/29) Salinometer - fully outfitted including the chemical to kill algae and at least two spare heating lamps Pinger for wire use Fume Hood Refrigerator -70 Deg Freezer Walk-In Cooler antivibration table for microscope work WHOI-Provided Equipment: Science Party-Provided Equipment: Notes: Night Work Anticipated We request to leave batteries and hazardous material onboard until Atlantis returns to a US port Science party requests to use ship's drill press (EC 8/29) Science party (Andreas) will supply salt bottles (4 cases) obtained from Scripps Standards? (EC 8/29) ALVIN/JASON Installed or Normally Carried USBLS Navigation Equipment: Doppler/GPS Navigation Large Capacity Slurp Pump - Single Chamber Small Capacity Slurp PUmp Bio Box (12x12x12 & 12x12x24) Scoop Nets High & Low Temperature Probe CTD Digital Still Camera - Oriented Forward Search Sonar Profiling Sonar Elevator Homer probe and receiver Science Party-Provided Mullineaux bioboxes (for block collection) Equipment: Bright Bioboxes (40 cm high, 20 cm x 25 cm) Notes: Other Notes: Our over-the side activities will be: 1) large mooring recoveries (Worrilow), 2) CTD/LADCP lowerings, 3)Microprofiler deployments and recoveries (St. Laurent), 350 lbs in air, floats untethered, planned to deploy off starboard side using ship crane and will move on rolling cradle to be worked on between deployments. (JD 8/29) 4)Plankton pump deployments and recoveries (Mullineaux), 5) Sediment trap mooring recoveries, 6) Elevator deployments and recoveries. We would like to use the same starboard winch, connections and capstain as for our 2006 LADDER cruises. We'll need to discuss with bosun about switching the block between CTD and deployments of moorings and microprofiler We would like to use the salinometer, fully outfitted including the chemical to kill algae and at least two spare heating lamps. We will need the antivibration table for microscope work The ADCP should be 75 KHz SSSG Tech: sssg @atlantis.whoi.edu Navy Clearance Granted 11/13/07: Status: WITHIN 100 NM RADIUS OF 09-30N 104-15W DURING PERIOD 150700Z NOV THRU 030700Z DEC 07 Check List: Required? Comments US Customs Form Yes Diplomatic Clearance No Isotope Use Approval No SCUBA Diving No Last Modified: 11/14/2007 References Visible links 1. http://www.ldeo.columbia.edu/~ant/LADDER 2. mailto:vtudoran@aol.com 3. mailto:danielromo2003@yahoo.com.mx