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Stabilized Iron
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2021
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Thomas G. Thompson
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Project Title: |
Collaborative Research: Are low temperature hydrothermal vents an important but overlooked source of stabilized dissolved iron to the ocean? |
Project Status: |
Submitted |
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Principal Investigator: |
Joseph Resing, UW |
Project Institution: |
UW |
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Project ID: |
105391 |
Version #: |
9 |
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Date Submitted: |
7/31/2017 8:41:00 PM |
Created By: |
Joseph Resing |
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Date Last Modified: |
12/4/2020 8:19:00 PM |
URI Serial #: |
None |
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Funding Agencies: |
NSF/OCE/CO - 1756402 - Funded |
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Summary of Field Work: |
Conduct CTD and AUV work along ridge crest of S East Pacific Rise.
This project will use 5 individual tows to hydrographically survey the ridge crest between 15 and 18 S along the EPR. An AUV will be flown in tandem with the towed CTD package. This work will be followed up with targeted CTD casts, fine scale AUV grid surveys, and shorter towed surveys perpendicular to the ridge crest. In addition this project will conduct multiple CTD casts between the ridge crest and Tahiti.
For planning purposes we will sail to 15 °S 112.5°W, and begin a series of five ~80 km CTD tows and simultaneous AUV tracks south along the EPR axis (~30-32 hr AUV surveys followed by ~16 hr periods for recovery, recharge and launch back to the seafloor; see Fig. 4). Based on past results, we plan on a CTD tow speed of ~2.6-2.8 km/hr (1.4 knots). The AUV will programmed to survey at a fixed altitude of ~50 mab and at the slightly faster speed of ~3.1 km/hr (1.66 knots) allowing it to maintain pace with the ship (and the CTD survey) while following a zigzag pattern that allows it to survey out to ±200m to either side of the ship’s track. Both the AUV and CTD-rosette package will be navigated in real-time using ship-based USBL navigation, with the AUV proceeding ahead of the CTD-rosette that is trailed behind the ship. Total survey time for five 80 km segments, including launches, recoveries, vehicle coordination, and battery charging will be ~10 days. During AUV charging, CTD casts will be conducted at sites of interest. We will also conduct six comprehensive AUV grid surveys (24 hr. ea. = 6 days not including recharging). The locations of the AUV grid surveys will be placed in areas of interest identified during along-axis surveys. Each dive will extend ~5-8 km along axis and ~200-400 m across axis with ~40 m spacing between lines. Each grid survey will end with a photo survey located in an area with the most extensive activity identified in real time during the grid survey. The photo survey will be a grid covering ~400 x ~150 m with 10-15 m line spacing. During AUV grid surveys, we will conduct hydrocasts at sites of interest within the grid, including at those identified in real-time by the AUV (previous work by us indicates that CTD casts conducted within the grid allows the AUV to maintain high-resolution navigation). Additional CTD casts will be conducted between dives at sites located within 10’s of meters of their sources as identified during grid surveys. The remaining time (7 days plus 2 days contingency = 9 days) will be for more detailed follow-on CTD-rosette sampling. It should be noted that the various survey techniques will not be sequential but will be interlaced with other activities to optimize operations; thus the “remaining” days will take place throughout the cruise, including during AUV grid surveys and recharge intervals. CTD casts will be made at as many diffuse sites as possible, at one or two high-temperature sites that are surrounded by extensive diffuse flow, between active sites as practical, across the ridge axis at one or more locations, and off axis where elevated dFe was found down to 3000 m during the EPZT (Fig. 1). If Tahiti is one of our ports, we will conduct a minimum of 5 hydrocasts between 2000 and 3500m depth (3 hrs. ea.) along our transit path which crosses a gradient of historic 3He values. |
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Summary of Facility Requirements: |
We will bring two CTD packages, our hydrothermal CTD package will operate off the ship's primary hydrowire (it has a plate that allows deployment from the latest deployment/recovery deployment cranes). The second package will require an additional winch spooled with Vectran (plastic-coated Kevlar) hydrowire. The spare GEOTRACES Vectan hydrowire is available and would need to be spooled onto a UNOLS winch-pool winch. We note that the GEOTRACES winch which will be on the Revelle for the GEOTRACES PMT cruise ending in Tahiti in November 2018.
We would like the ship’s CTD to be available as a back-up.
We require an AUV for our proposed survey. Our first choice at this point is Sentry.
We will use the ships deep water multibeam and will collect ADCP data.
We require a UNOLS trace metal sampling van. |
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Summary of other requirements and comments: |
We propose that one of our ports be Tahiti to allow us to conduct hydrocasts to characterize the distal water plume. We can accomplish our task with Tahiti at either end, but prefer to have Tahiti as the initial port. |
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Type of Request: |
Primary Ship Use |
Request Status: |
Submitted |
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Request ID: |
1008676 |
Created By: |
Joseph Resing |
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Date Last Modified: |
12/4/2020 8:19:00 PM |
Date Submitted: |
7/31/2017 8:41:00 PM |
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Year: |
2021
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Ship/Facility: |
Thomas G. Thompson
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Optimum Start Date:
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8/1/2021 |
Dates to Avoid: |
N/A |
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Earliest Start Date: |
11/1/2018 |
Multi-Ship Op: |
No |
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Latest Start Date: |
9/18/2021 |
Other Ship(s): |
N/A |
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Operating Days Needed: |
Science Days |
Mob Days |
De-Mob Days |
Estimated Transit Days |
Total Days |
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25 |
3 |
2 |
24 |
54 |
Repeating Cruise?
(within same year) |
No |
Interval: |
N/A |
# of Cruises: |
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Description of Repeating cruise requirements: |
N/A |
Justification/Explanation for ship choice, dates,
conflicts, number of days & multi-ship operations: |
The Revelle, Thompson, and Atlantis are acceptable ships for this project. If push came to shove, we would reevaluate the size of our science party with respect to the berthing available on the Sally Ride. The chosen ship will need to be able to spool the spare Geotraces Vectran wire onto UNOLS winch-pool winch. Greg Cutter has offered us the spare Vectran Wire for our cruise. Preferably, installation of the Geotraces Winch, vectran cable, and small a-frame would be preferred.
We will use the ship to do a series of five ~80 km CTD tows and simultaneous AUV tracks south along the EPR axis. We plan on a CTD tow speed of ~2.6-2.8 km/hr (1.4 knots). The AUV will programmed to survey at a fixed altitude of ~50 mab and at the slightly faster speed of ~3.1 km/hr (1.66 knots) allowing it to maintain pace with the ship (and the CTD survey) while following a zigzag pattern that allows it to survey out to ±200m to either side of the ship’s track. Both the AUV and CTD-rosette package will be navigated in real-time using ship-based USBL navigation, with the AUV proceeding ahead of the CTD-rosette that is trailed behind the ship. |
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Short Description of Op Area
for use in schedules: |
SEPR |
| Description of Op Area: |
The Southern East Pacific Rise between 15 and 18S and five to 10 stations between the SEPR and Tahiti. |
| Op Area Size/Dia.: |
250 |
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Lat/Long |
Marsden Grid |
Navy Op Area |
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Beginning
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17° 36' S
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148° 54' W
map
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Ending
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18° 30' S
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114° 0' W
map
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Show Degrees Minutes |
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Foreign Clearance Required? |
Yes |
Coastal States:
French Polynesia |
 Important Info on Foreign Research Clearances
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Are you or any member in your science party bringing in any science equipment items which are regulated for export by the International Traffic in Arms Regulations (ITAR) and/or the Export Administration Regulations (EAR)?
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Yes |
If yes, have you applied for the necessary permits through your export control office?
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No |
| Questions about ITAR/EAR regulations?
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Comments about foreign clearance requirements or
description of any other special permitting requirements
(e.g., MMPA, ESA, IHA, Marine Sanctuaries, etc.) |
The AUV equipment will be regulated. Nothing else brought by the scientific party will be so regulated.
AS of now we are not going into French Polunesian waters, however we remain open to using Tahiti as our port of departure. |
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Requested Start Port |
Intermediate Port(s) |
Requested End Port |
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Papeete, Tahiti, French Polynesia |
None |
Papeete, Tahiti, French Polynesia |
Explanation/justification for requested
ports and dates of intermediate stops
or to list additional port stops |
Our science program were supposed to include CTD-hydrocasts between Tahiti and our primary study site. We recognize that will not happen now with ports SD to SD. We remain open to Tahiti as a start port. Mobilization/demob of major equipment would then be at the major port prior to the transit. We would always prefer Easter Island as an interim port at one end or the other, but recognize that that may not be feasible. |
Important Info on Working in Foreign Ports
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Chief Scientist: |
Joseph Resing, UW |
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# in Science Party |
26 |
# of different science teams |
4 |
# Marine Technicians to be
provided by ship operator:
(include in science party total)
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2 |
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Explanation of Science Party Requirements and Technician Requirements |
We will have a main science team of approximately 18 to 20, an AUV team of 6, and a ship's res-tech crew of 2. WE hope to have scientists on board from the UK and China. |
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 Dynamic Positioning | ADCP | Multibeam |  Seismic |
| Dredging/Coring/Large Dia. Trawl Wire | Stern A-frame | Fiber Optic (.681) | 0.680 Coax Wire |
| SCUBA Diving | Radioisotope use - briefly describe | NO Radioisotope use/Natural level work | Other Operator Provided Inst. - Describe |
| 4 PI-Provided Vans - briefly describe | MOCNESS | | |
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Explain Instrumentation or Capability
requirements that could affect choice
of ship in scheduling. |
We have arranged to us the Geotraces winch and a-frame. We need to be certain to keep this capability. Since this proposals funding and throughout all the delays, a new trace metal winch and wire capability has come available at University of Georgia that was funded by NSF. The UGA system probably does not have an A-Frame. The winch pool will also need to provide a trace-metal compatible block.
Two laboratory Vans for trace element work will be placed on the ship. Preferably on the fan tail. We may also want to provide an empty van for loading and unloading depending on final ports and transits.
Sentry will also provide two vans for their operations.
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Explain Major Ancillary Facilities
Requirements and list description
and provider for "other" systems. |
We look to use the AUV Sentry.
The Geotraces Winch spooled with Vectran wire has been requested from the WHOI winch pool.
To support our cruise we require a Clan Lab van. |
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