West Coast Expedition
July 20 - August 30, 2002
West Coast of North America
Equipment

Ship & Vehicle : R/V Western Flyer and the ROV Tiburon
(R/V = Research Vessel,   ROV= Remotely Operated Vehicle) 

LEG 1: Manipulator, drawer with partitions, pushcores with and without catchers, high-temperature water bottles, temperature probe, bio box to fit in drawer, glass suction sampler, biologic suction sampler with screen (both suction samplers at once if possible). Night operations may utilize the rock crusher with MPR self-contained CTDs clamped to wire. Maximum of 4 elevator deployments.

LEG 2: We will use standard benthic toolsled for all dives. Will carry the Tivey magnetometer, ICL and temperature probes for all dives. Will use modified radium sampler for low-temperature fluids. Will also use Seewald gas tight fluid samplers and WHOI Ti-syringe samplers. Will need to use elevators for first two dives to recover fluid samplers and sulfide at beginning of dive. Will also use Tiburon wax push cores.

The isobaric fluid sampler is designed for collection of hydrothermal fluids venting at the seafloor. The device is constructed of chemically inert titanium, is gas-tight to 450 bars and can be used to sample fluids with temperatures up to 400°C. Compressed gas is used to maintain the sample at seafloor pressure before and during sample withdrawal onboard ship, allowing subsampling without degassing the fluid remaining in the sampler. This feature eliminates the need to collect separate gas-tight and major element samples since a single fluid sample can be analyzed quantitatively for major, trace, semi-volatile, and volatile components. The sampler fill rate is regulated to minimize entrainment of ambient seawater during collection of fluids from environments characterized by low fluid flow such as diffuse hydrothermal vents. In addition to deployment at the ridge-crest, the samplers can be used to collect gas-tight samples from other subseasurface environments such as hydrocarbon seeps, areas of methane-gas hydrate formation, cold seeps associated with serpentinites, regions of groundwater egress to the oceans, and the water column.

The ICL (Inductive coupled Link) is a simple non-contact way to get data in or out of an instrument using a connection method that is within the dexterity capability of current mechanical manipulators. It works in air or water and can accommodate up to 9600 baud reliably. It requires almost zero power when listening and less then 10 mW when transmitting so it works well in battery powered systems. The link is done with two 4” diameter coils of wire that communicate reliability when brought within about 3” of each other axially. It is shown here being used to download data from one of Marv Lilley's temperature-resistivity probes (ICL loop is over the cone on Lilley's datalogger). Why Do We Use ICLs? The ICLs fill an important gap in the way we do benthic science. The history of deep submergence science is full of sad stories of year long deployments where some sad scientist discovered on reading the data that there wasn’t any. Sometimes the instrument failed as it got kicked around leaving the deck. Others failed due to a pressure effect on the trip to the bottom. Often the placement on the bottom wasn’t optimum. If we could just check the operation of our instruments after they’re in place we’d have a chance to adjust or fix things. This need led to the development of the ICL. We can talk to the instruments at any time in the lab, on deck and on the bottom just by dropping a coil over a guide post (containing the instrument’s coil). When the instrument is in place on the bottom we can check the data quality, upload some or all of the data recorded so far or change sampling rates or any other parameter without disturbing the placement of the instrument.

LEG 3: CTD with rosette niskin bottles, transmissometer, oxygen, (etc-standard sensors) for at least 2600-3000 m water depth, Tiburon high and low temperature probes, titanium major fluid samplers, benthic sled, drill sled, push cores, wax cores, small elevator, homer pros 6 for Keck + at least 5 additional, Sonardyne Compaq, vacuum to clean out holes, plugs for coreholes, Al Bradley model 4" ICL, appropriate core liners, drill bits, at lest 6 extra "regular" push core sleeves, at least 2 science ports to bring data up wire from Tiburon. (temperature-resistivity probe and sulfide insert will use ICL, UW high temperature probe will need a port), annotated video on UW copy, cool pix camera, modified Kraft arm for water sampling, radium sampler. Instruments the UW is bringing out to use/deploy include: gas-tight fluid samplers, temperature-resistivity probe, 23" sulfide microbial incubator, metz methane sensor, high-temperature probe, vent site markers.