Scientific Prospectus for R/v atlantis /rov
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- Navigate this page:
- Expedition Dates and Ports
- Table 1
- II. AT25-04 Objectives and Experimental Systems
- Figure 4
- Figure 6
- III. AT25-04 Draft Dive Plan
- IV. Education, Outreach and Communication
- V. Staffing, Logistics, Planning, and Safety
- Location ID Latitude Longitude Water depth (m)
- Location ID Exchange/ Recover OS
- Hole 1026B Hole 1362A Hole 1362B
- Number Last name First name Institution
| Scientific Prospectus for R/V Atlantis/ROV Jason II Expedition AT25-04:
Hydrogeologic, Geochemical, and Microbiological Experiments in Young Ocean Crust of the Northeastern Pacific Ocean Using Subseafloor Observatories Expedition Dates and Ports: 13 July 2013 to 26 July 2013, Astoria, OR to Astoria, OR (mobilization: 11–12 July 2013, demobilization 27–28 July 2013) Supported by NSF project: OCE-1031808 (and linked proposals to Fisher, Becker, Clark, Cowen and Wheat) and a C-DEBI Education and Outreach grant (to Cooper and Peart) Project Co-PIs: A. T. Fisher1, 3, K. Becker1, J. Clark1, S. Cooper2, J. Cowen1, C. G. Wheat1 1 Co-PI on OCE-1031808 and linked proposals 2 Co-PI on C-DEBI Education and Outreach grant 3 AT25-04 chief-scientist and primary contact: Earth and Planetary Sciences Department, Earth and Marine Sciences Building, Room A232, University of California, Santa Cruz, 1156 High Street, Santa Cruz, CA 95064, 831-459-5598, 831-459-3074 (fax), afisher@ucsc.edu Prospectus Draft/Final 1.2: 26 April 2013 I. Expedition Overview NSF grant OCE 1031808 ("Collaborative Research: Completion of single- and cross-hole hydrogeologic experiments on the eastern flank of the Juan de Fuca Ridge using a borehole network") supports multidisciplinary borehole experiments in oceanic crust, to assess hydrogeologic, solute and colloid transport, biogeochemical, and microbiological processes and properties at multiple spatial and temporal scales (meters to kilometers, minutes to years). Results of these experiments will comprise a major advance in our understanding of hydrogeologic properties and fluid processes within the volcanic oceanic crust. This work follows completion of Integrated Ocean Drilling Program Expedition 327, which operated in Summer 2010, R/V Atlantis/ROV Jason II Expedition AT18-07 in Summer 2011, and numerous earlier drilling and submersible/ROV expeditions. This expedition was originally planned for Summer 2012 on the R/V Thomas G. Thompson, but was postponed because of ship propulsion problems, then rescheduled on the R/V Atlantis for Summer 2013. Primary work locations are summarized in Table 1 and shown in Figures 1, 2, and 3. Integrated Ocean Drilling Program Expedition 327 drilled two holes through sediments and into the volcanic crust on 3.5 m.y. old seafloor on the eastern flank of the Juan de Fuca Ridge (Figures 1, 2, and 3). These holes were drilled, cased, cored, and tested, then instrumented with subseafloor, borehole observatory systems (CORKs). Expedition 327 also included a hydrogeologic, pumping and tracer injection experiment, to assess multi-scale formation properties, including the nature of azimuthal and vertical crustal anisotropy. The Expedition 327 CORKs augment four additional observatory systems, all located within an area of about 2.5 square kilometers, creating a network of six instrumented sites where researchers are monitoring pressure and temperature at depth, and sampling fluids and microbiological material, using autonomous instrumentation (Figure 3). These CORK systems require servicing with a submersible or remotely operated vehicle (ROV) to download data, recover samples, and replace a variety of experimental systems (pressure and temperature data are being collected from one of the systems using a cabled network). This is a primary goal of the Summer 2013 Expedition AT25-04 with the R/V Atlantis and ROV Jason II. In addition, we will recover a flowmeter currently installed on one of the CORK observatories, and close a large-diameter ball valve, shutting off the discharge of hydrothermal fluid that was initiated in Summer 2011. Data from this flowmeter will be downloaded, and the instrument will be redeployed on another wellhead, and a large-diameter ball valve on that wellhead will be opened, initiating flow from the CORK. These free flow experiments create pressure perturbations at surrounding CORKs. Free flow also provides fluid and microbiological sampling opportunities. By monitoring the formation pressure response at the different observatories, located at different distances, depths, and directions from the CORK that will be allowed to discharge fluid, researchers will be able to assess the nature of crustal hydrologic properties. Wellhead instruments deployed in Summer 2011 (fluid samplers, microbial growth incubators) will be recovered and replaced. A GeoMicrobiology sampling sled deployed on one wellhead in Summer 2011 will be recovered, and additional (active) fluid sampling will be complete at various wellheads. We will recover a short downhole instrument string from the CORK in Hole 1301A, and seal that CORK with a simple top plug. The primary set of grants supporting this expedition includes 11 dives/science days, two days of transit, and one weather day, for a total expedition length of 14 days. ROV dives with Jason can last just a few hours or more than 24 hours, depending on objectives, weather conditions, and mechanical functioning of ship and ROV systems. For planning purposes, we assume ROV dives with a nominal length of 24 hours, with 12 hours for ROV servicing, allowing for seven 24-hour dives during our allotted time at sea (and assuming no lost days due to weather or mechanical problems). In addition to meeting scientific and technical goals, AT25-04 will include a significant education, outreach, and communications (EOC) program, with funding provided by NSF and C-DEBI, and with extensive technical and logistical support from WHOI, the Ocean Exploration Trust, and the Inner Space Center at URI. The AT25-04 EOC program is likely to include a diverse combination of: (a) live feeds/web conferencing with museums, summer camps, and other venues, (b) production of videos, podcasts, and other media to be distributed via the web, (c) blogging and (d) curriculum development by onboard educators and outreach specialists. Secondary objectives for AT-25-04 include downloading pressure data from additional CORKs located to the west (Figure 2), conducting multibeam surveys of outcrops close to the primary work sites, testing of a new heat flow probe insertion and stabilization system, and other activities. If these secondary objectives are attempted, this will occur most likely towards the end of the expedition.
Primary objectives to be completed during dives at the six primary CORKs are listed in Table 2. CORK servicing tasks include: download pressure data, recover/exchange wellhead OsmoSamplers, complete active fluid sampling, recover the GeoMicrobiology sled, recover a downhole instrument string, and recover/deploy the flowmeter. Each CORK is different, but they share some common components (Figure 4). Because the six primary CORKs are located close together (Figure 3, Table 3), operations at multiple wellheads can be combined during single dives. During AT18-07, we transited between CORKs up to 2400 m apart, requiring 1 to 1.5 hours to move and get set up for new operations. Sharing operations between multiple wellheads can result in considerable efficiency, but also requires careful planning and (in many cases) use of elevators to deploy and/or recover instrumentation so as to avoid overloading the ROV. Careful planning is also required to minimize the need to swap out connectors and experimental systems between dives. Active pressure measurement and logging systems are currently installed as part of all six primary CORKs (Figure 5). Data from Hole 1026B are being downloaded automatically using the Neptune Canada cable network. Data from the other CORKs will be downloaded with Jason. Pressure download operations will include manipulation of valves for checking the hydrostatic pressure offset and evaluate potential gauge drift. Most pressure logging systems will be downloaded once during the expedition, but it is possible that a second download may be required at one or more CORKs in association with the long-term flow experiment. Pressure logging systems are positioned vertically on the wellheads, with the exception of the CORK in Hole 1027C. The data logger for this system rests horizontally on the ROV landing platform. OsmoSampler systems are currently installed on all (primary) CORK wellheads except for Hole 1027C (Figure 6). There are two basic types of wellhead OsmoSamplers: (1) vertical design with sample coils and pumps installed vertically on metal plates (Figures 6A-C), and (2) milk crate design with sample coils and pumps hung from the wellhead, and an umbilical tube that connects to fluid sampling lines (Figures 6D-F). The former are currently installed on CORKs in Holes 1026B, 1301A, and 1301B, whereas the latter are installed on newer CORKs in Holes 1362A and 1362B. For each design, there are additional variations: Teflon coils, copper coils, and microbiological FLOCS incubation chambers mounted inline with sample pumps and tubing. Existing systems will be recovered and new systems will be installed during AT25-04. We will also recover a short instrument string deployed in the CORK in Hole 1301A, then seal that CORK with a top plug when the instrument string is recovered. We hope to accomplish this operation using Jason and the support vehicle Madea, but it could be done using floatation and a special winch brought to sea specifically for this purpose. Discussion is underway with the deep submergence team as to how best to accomplish string recovery operations. A variety of "active" (mainly short-term) fluid sampling systems will be handled during AT25-04 (Figure 7). A large volume bag sampler will be deployed using Jason elevators, and a medium volume bag sampler will be mounted in the rear Jason basket. These systems use a pump and manifold, in-line analysis and/or filtering, and additional components (aka, "Mobile Pumping System") to collect, analyze, and store samples drawn from CORK wellheads. We will recover (but not redeploy) a long-term, GeoMicrobiology sampling and analysis sled that was deployed on Hole 1362B in Summer 2011. An elevator equipped with many of the GeoMICROBE sled’s instruments (e.g., pump, manifold, controller, batteries) will be used for short-term (24 hour) intensive time-series sampling of basement fluids for biogeochemical and microbial diversity short-term variability; this elevator will be referred to as a Modified GeoMICROBE (or MGM) elevator. In general, samples collected with these systems should be recovered as soon as possible after collection, which will require use of elevators and/or scheduling for end of dives. Additional gas-tight, major ion, and squeeze samplers will also be used throughout the expediton. We developed an autonomous flowmeter system that was deployed on the top of a ball valve in the wellhead of the CORK in Hole 1362B during AT18-07 (Figure 8). This flowmeter uses an electro-magnetic induction sensor to determine the rate of fluid outflow from the CORK over time, and has been recording hourly data for the past year. The flowmeter is held in place with a rotating clamp built into a ball valve positioned in one of the wellhead bays. Opening that valve started a long-term flow experiment, as the overpressured formation discharged shimmering (~65 °C) fluid at 5–20 L/s. Pressure data from this hole and nearby CORKs will be used with the flow data to determine large-scale, directional hydrologic properties in the ocean crust. There is a vertical PVC pipe with a diameter of ~4 that extends upward from the flowmeter sensor by about 1 m. Four autonomous thermal loggers are installed along the length of this pipe, to provide an independent estimate of the upward fluid flow rate (using heat as a tracer). In addition, this pipe has provided fluid and microbiological sampling opportunities, with inlets to fluid samplers "hung" over the top of the pipe. Handling of this flowmeter system was challenging in Summer 2011 because of awkward placement of a handle and bridle. A new flowmeter system is being constructed for Summer 2012, with an integrated handle assembly (Figure 8F). The flowmeter currently deployed will be recovered, and either this instrument will be redeployed (on another CORK, using the new handle) or the new flowmeter system will be deployed. The new system is very similar to the old one, except that it has optical communication capabilities.
AT25-04 mobilization in Astoria, OR will occur on 11-12 July (according to current ship schedule). Ship will depart early on 13 July, with an anticipated transit of ~24 hours to our first work site. We have 14 operating days at sea, which will comprise approximately 12 days of scientific work (11 days scheduled science, 1 day weather/mechanical contingency) and 2 days of transit. For planning purposes, we assume that each ROV dive lasts 24 hours, with 12 hours between dives for ROV servicing, deployment and recovery of elevators, and other activities. In practice, ROV dives will have variable duration, depending on tasks attempted, mechanical and weather conditions, and other factors, and servicing time intervals could be longer or shorter than 12 hours. Draft plans for initial several dives are listed below, but we will continue discussion among the research team and with the WHOI and Jason teams to optimize activities and address the highest priority objectives early in the expedition. No matter how the dives are planned, we will likely shift the sequence of operations somewhat based on at-sea conditions and results of initial work. We will also prepare a more detailed listing of electrical and basket requirements, item weights and dimensions, and other information. For the dive activity list below, abbreviations for various active sampling systems: MPS = Mobile pumping system, basic, pump system in a milk crate that rides on the right side of the forward science basket. MVBS = Six, 15-L bag sampler system that rides in aft Jason bay. LVBS = 50-L bag sampler that rides on the forward science basket (fills quickly). MGM Elevator = Modified GeoMICROBE elevator used for ~24 hr time-series sampling. Dive 1 Location: Hole 1362B Goals: Close flowmeter valve, recover flowmeter, hydrostatic check, download pressure data, swap OS systems, recover GeoM sled, collect fluids from wellhead. Basket: ODI connector, fluid sampling (various)/in-line electrochemistry, MPS-MVBS, LVBS (? space available?) Elevator(s): (1) Deploy empty for instrument recovery…or with OsmoSamplers for 1362B? (2) Deploy MGM elevator near 1362B
Deploy elevator with new OS systems near 1362B, other? Dive on 1362B Collect fluids exiting flowmeter (Majors? Gas tight? Squeeze?) Close valve below flowmeter Close sampling valves in Geochem bay, MBIO bay Recover OS systems from wellhead, put on elevator? Turn valve on pressure line to get hydrostatic (wait 30 minutes) Turn valves back to formation (wait 30 minutes) Deploy new OS systems on wellhead (leave sampling valves closed until later) Recover flowmeter, place on elevator and secure in place Download pressure data (60+ minutes after closing all valves) Collect fluids from wellhead using LVBS, MVBS in Jason? Disconnect GeoM sled Connect MGM sled (short-term (24 hr) time-series sled) to 1362B bioline (not sure if time/space will permit) Recover GeoM sled Fly around wellhead and shoot video, photograph Recover elevator Dive 2 Location: Holes 1362A, 1301A, 1301B Goals: Replace OsmoSamplers on 1301A and 1362A, collect wellhead fluids from 1362A, hydrostatic check, download pressure data from 1301A, 1301B, 1362A Basket: ODI connector, fluid sampling (various)/in-line electrochemistry, MPS-MVBS, LVBS Elevator: OsmoSamplers for 1362A and 1301A? Tasks: Launch elevator adjacent to 1301A Dive on 1301A Close fluid sampling valves Recover OsmoSamplers (place on elevator?) Turn valves on pressure lines to get hydrostatic (wait 30 minutes) Turn valves on pressure lines to get formation (wait 30 minutes) Deploy new OsmoSamplers Download pressure data Fly around wellhead and shoot video, photograph Transit to 1301B Turn valves on pressure lines to get hydrostatic (wait 30 minutes) Turn valves on pressure lines to get formation (wait 30 minutes) Download pressure data Fly around wellhead and shoot video, photograph Transit to 1362A Close fluid sampling valves Recover OsmoSamplers (place on elevator?) Turn valves on pressure lines to get hydrostatic (wait 30 minutes) Turn valves on pressure lines to get formation (wait 30 minutes) Deploy new OsmoSamplers (leave sampling valves closed initially) Download pressure data (60+ minutes after closing all valves) Collect fluids from wellhead using LVBS, MVBS (one level, both levels?) Fly around wellhead and shoot video, photograph Recover elevator Transit to 1362B Close valve, disconnect MGM sled, release to surface and recover
Dive on Hole 1027C Hydrostatic check (wait 30 minutes) Turn valve back to formation (wait 30 minutes) Download pressure data Fly around wellhead and shoot video, photograph Transit to 1026B Remove old OsmoSamplers Install new OsmoSamplers Fly around wellhead and shoot video, photograph Transit to 1362A Collect fluids from wellhead using LVBS, MVBS (one level, both levels?) Position and connect MGM elevator to 1362A deep bioline Fly around wellhead and shoot video, photograph Dive 4 Location: Hole 1362A, 1362B Goals: Open open fluid sampling lines to OsmoSamplers valves on 1362B, deploy flowmeter on 1362A, open fluid sampling lines to OsmoSamplers, confirm operation, download pressure data, wellhead sampling Basket: ODI connector, flowmeter Elevator: ??? Tasks: Dive on Hole 1362B Open sampling lines to OsmoSamplers on wellhead, confirm operation(?) Fly around wellhead and shoot video, photograph Transit to Hole 1362A Disconnect MGM elevator Release elevator to surface Deploy flowmeter on wellhead Open large diameter valve, initiate flow from deep interval Open sampling lines for OsmoSamplers on wellhead Deploy OS on flowmeter chimney Download pressure data Collect fluids from wellhead using MVBS (one level) Fly around wellhead and shoot video, photograph Dive 5 Location: Hole 1301A and 1362B Goals: Open fluid sampling line(s) to OsmoSamplers, confirm operation, wellhead sampling Basket: fluid sampling (various)/in-line electrochemistry, MPS-MVBS, heat flow probe? Elevator: MGM elevator (check weather forecast, etc.) Tasks: Dive on 1362B Collect fluids from wellhead using LVBS, MVBS at 1362B Transit to 1301A Collect fluids from wellhead using LVBS, MVBS Fly around wellhead and shoot video, photograph Attach Otis tool to wellhead, pull out with Medea, recover with vehicle (return later to install plug)
Dive on 1301A Install plug in wellhead Fly around wellhead and shoot video, photograph Complete primary objectives that could not be completed during earlier dives Complete subset of some secondary activities: Final data download from 1027C, after initiation of new flow experiment? Test heat flow probe insertion frame? Short-term fluid sampling at 1362A?
Complete primary objectives that could not be completed during earlier dives Complete subset of these secondary activities: Test heat flow probe insertion frame Final data download from 1027C, after initiation of new flow experiment? Short-term fluid sampling at 1362A? Download pressure data at CORK in Hole 1024C and/or 1025C Mapping/sampling at Mama Bare, Papa Bare, or Zona Bare outcrops IV. Education, Outreach and Communication We have a variety of education, outreach, and communication (EOC) activities planned for AT25-04, and a dedicated group of EOC specialists who will work with the rest of the shipboard party on these activities. Overall, the EOC program will emphasize the nature and process of science – how we ask questions, test ideas, gather data, problem-solve, circle back to new questions and collaborate with both the local, on-board community of participants and the broader science community at large – in the service of a transformative research agenda. The EOC program will also help scientific and technical personnel to be more effective in engaging and communicating with a diverse community of shore-based non-specialists. The AT25-04 EOC program is, in some ways, a longitudinal extension of earlier EOC efforts involving education al personnel who have gone to sea during IODP expeditions, including the web-based Adopt-A-Microbe program, and EOC work during and after AT18-07. There is at least one key difference between EOC activities planned for AT25-04 and those run on earlier expeditions: we plan to have a high-bandwidth "tele-presence" capability through technical and personnel support being organized by the AT25-04 team, and experts/support staff from WHOI, the Ocean Exploration Trust, and the Inner Space Center at URI. The details of the EOC syllabus and operational plan are being defined, but are likely to include: Live video broadcasts with camp, school, museum and other audiences. We will be setting up scheduled events in advance, using a newly developed high-bandwidth system to hold live web conferences that connect shipboard and shore-based personnel. Blogging about shipboard experiences. We will provide a blogging platform and assistance in developing web materials, connecting to shore-based groups, responding to queries, etc. Preparing video and/or written scientist profiles and expedition updates. We will have a professional videographer and videography teacher onboard, who will be working on shooting and editing short videos during the expedition, and teaching EOC and other personnel how to work with modern video production technology (cameras, editing software, etc.) in addition to the basics of lighting, sound, and other aspects of media production. Developing classroom activities related to science and engineering goals and process. Our EOC team includes both secondary school and museum educators, who will work on projects to integrate topics and activities related to AT25-04 in their respective settings. Assisting shipboard staff with achievement of primary expedition objectives. There will be an emphasis on both group activities and collaboration among the EOC team, and in completion of projects that are defined individually and in consultation with subgroups of scientific investigators. Our intention is to integrate EOC participants and contributing members of the scientific enterprise. V. Staffing, Logistics, Planning, and Safety We anticipate sailing 24 scientific and education, outreach, and communication (EOC) personnel, in addition to the regular WHOI technical support and Jason support teams. The current staffing list is summarized in Table 5. General information on WHOI Cruise Planning can be found here: http://www.whoi.edu/main/cruise-planning Information on the R/V Atlantis is available here: http://www.whoi.edu/main/ships/atlantis Information on the ROV Jason II is available here: http://www.whoi.edu/ndsfVehicles/Jason/ Information for project co-PIs is available here: http://www.whoi.edu/page.do?pid=8218 Information for members of the science/EOC party is available here: http://www.whoi.edu/page.do?pid=8219 This is a set of information and forms (some of which are discussed below) that all expedition participants should review and complete (as needed): http://www.whoi.edu/page.do?pid=12795 Hazardous materials Anyone bringing hazardous materials must read this page and associated links, and fill out forms as needed: http://www.whoi.edu/page.do?pid=8336#0
We don't plan to have any radioisotope work done during AT25-04. All members of the AT25-04 shipboard party must have closed toed and closed backed shoes on board the vessel. Open toed and open backed shoes are only allowed in cabins. Crocks, sandals, and similar types of shoes are NOT considered closed toed and are NOT allowed on deck or in the lab. Sneakers, boots, hiking and similar shoes are considered closed toed and allowed on deck and in the lab. Steel-toed shoes are recommended when working on deck. If you will be deploying instruments over the side, like moorings or large deployments, steel-toed shoes are required. Table 1. Primary work sites for Summer 2013 with the R/V Atlantis and the ROV Jason II on AT25-04. Clearance is requested for 0.5 nmi around each CORK.
Table 2. Summary of tasks to be completed at each of the primary CORKs in Summer 2013 with the R/V Atlantis and the ROV Jason II on AT25-04.
NA = not applicable 1 OS = OsmoSampler. Several different kinds of OsmoSampler systems are to be deployed on and recovered from CORK wellheads (not from downhole). E = exchange. R = recover. 2 Active sampling means using mechanical pumps to draw fluids from wellheads, or sampling from direct flow from overpressured formations. 3 Flowmeter deployed on wellhead at Hole 1362B in Summer 2011, will be recovered and deployed at Hole 1362A. D = deploy. R = recover. 4 GeoMicrobiology sampling sled was left to draw fluids from CORK in Hole 1362B during AT18-07 in Summer 2011. 5 Pressure and temperature logging systems installed with CORK in Hole 1026B are currently being downloaded automatically with the Neptune Canada cabled network. Hole 1027C was retrofitted with a modern logger, using same ODI connector as other CORKs, during AT18-07 in Summer 2011. 6 String to be recovered from Hole 1301A was deployed in 2009, is ~275 m long and weighs ~400 lbs in air. Will be replaced with a top plug but no instrument string. Table 3. Distances between CORK systems (in meters) located at the primary work sites for Summer 2013 with the R/V Atlantis and the ROV Jason II on AT25-04.
Table 4. Secondary work sites for Summer 2013 with the R/V Atlantis and the ROV Jason II on AT25-04. Clearance sought in case all primary tasks are completed and time remains on the schedule.
Table 5. Anticipated scientific and EOC staffing for AT25-04 (as of 4/26/13). Open berths to be filled by some combination of scientific, technical or EOC personnel.
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