Dorado Outcrop and CR CORKs

Ship

R/V Atlantis

Vehicles

AUV Sentry, ROV Jason

Cruise Party

Andrew Fisher: Principal Investigator, Principal Investigator, Principal Investigator, Principal Investigator
UCSC 1156 High Street Santa Cruz, CA USA 95064
+1 831 459 5598


Samuel Hulme: Principal Investigator
Moss Landing Marine Laboratory USA
+1 831 359 1907
samiam0101@gmail.com

Geoffrey Wheat: Principal Investigator, Chief Scientist
University of Alaska Fairbanks P.O. BOX 757200 Fairbanks, AK USA 99775
+1 831 633 7033
wheat@mbari.org

Departure: Costa rica on Nov 30, 2013

Arrival: Costa Rica on Dec 23, 2013

Supporting documentation:

Operations Area: 86 to 88 degrees west 8 to 10 degrees north (TicoFlux site) and CR CORKs

Lat/Lon: 9° 0.0′ N / 87° 0.0′ W

Depth Range: 3000 / 4500

Will the vessel be operating within 200 NM of a foreign country? Costa Rica
Are visas or special travel documents required? no

Science objectives

Intellectual Merit: Scientific Motivation and Proposed Program

            Most of the advective heat loss from the oceanic lithosphere occurs on "ridge flanks”, areas far from the magmatic influence of seafloor spreading. Global hydrothermal fluid flows to and from the seafloor on ridge flanks, driven by lithospheric cooling and influenced by basement relief and variations in sediment thickness, are of the same magnitude as the flows from all of Earth's rivers and streams to the oceans. Yet, pristine fluids from a typical ridge-flank hydrothermal system have never been sampled, mainly because it has not been possible to locate a site of focused discharge where representative samples could be collected. We have located a small basement feature, Dorado outcrop, on 23 m.y.-old seafloor on the eastern flank of the East Pacific Rise, that is hypothesized to discharge 10³–10⁴ L/s of cool (10–20°C) hydrothermal fluid that carries 200-350 MW of lithospheric heat, equivalent to the heat output of a black-smoker vent field.

            We propose to sample this fluid to determine its composition, and to assess the rate of discharge from Dorado outcrop, so that we can quantify the chemical impact of this hydrothermal system. The physical and chemical state of this fluid is typical of fluids that extract heat from the crust and exchange solutes with the overlying ocean across much of the seafloor. Collection of uncontaminated samples from this feature will provide the most accurate estimates of the global impact of ridge-flank hydrothermal circulation. We anticipate that this fluid will be modestly different in composition from bottom seawater, which is why collection of pristine samples is so important, because of the relatively low temperatures of reaction and short residence time of the fluid within basaltic basement. Despite being slightly altered, fluid of this kind can have a large influence on the geochemical budgets of important solutes in the ocean because the flows are so large (from both Dorado outcrop and on a global basis).

            We propose an 18-day expedition that combines the surveying capabilities of the AUV Sentry (bathymetric, sub-bottom sonar, photo mosaics, water column anomalies) and an ocean-class vessel capable of collecting high-quality multi-beam data and CTD samples, and supporting the survey and sampling capabilities of the ROV Jason II for collection of spring and plume fluids, heat flow data, sediment push cores, and still and video photography. These data and samples will be combined to generate the first well-constrained estimates of hydrothermal flows from Dorado outcrop. This single expedition will result in the collection of samples and data from a “fire hose” of ridge-flank, hydrothermal system, challenging the commonly held view that discharge from ridge flank hydrothermal systems occurs primarily from diffuse seeps.

 

Broader Impacts

            Undergraduate and graduate students and a junior faculty member (Hulme) will gain experience by participating in this program and through the development of ROV manipulated samplers and sensors. Results of this work will be broadcast in publications, theses, presentations (to scientific and lay audiences), and in K-16 curriculum development. The P.I.s have strong histories of involvement in educational and outreach programs at multiple levels. Wheat and Hulme are developing hands-on science-technology packages to engage K-8 students during week-long learning opportunities that include three technology-based activities per grade level and meet national science, mathematics, and language arts standards. Fisher will involve university students through USCS’s Institute for Scientist and Engineering Educators and Cal Teach programs. Wheat and Fisher are involved in the NSF-funded Science Technology Center for Dark Energy Biosphere Investigations (C-DEBI). Materials from this expedition will be incorporated in C-DEBI education and outreach activities, reaching a diverse audience that includes K-8 students in the Los Angeles area.

Science Activities

WHOI support personnel estimate 8 hours of bottom time for a complete bathymetry survey of Dorado outcrop (216,000 m²/hr), yielding a processed map with 20-30 cm resolution. Subbottom penetrating sonar and water column thermal and eH surveys will be completed simultaneously and continuously during bathymetric mapping. The initial bathymetric map will guide additional Sentry dives to collect additional bathymetric and sediment thickness data on and surrounding the outcrop; should it be necessary, additional higher altitude (50 m) mapping of the outcrop perimeter will be conducted to ensure complete bathymetric and subbottom coverage of the outcrop and adjacent sediments. Sentry also will be used to conduct photographic surveys 5 meters above the seafloor (5400 m²/hr) during which we will monitor for thermal and chemical anomalies in the water column. WHOI personnel expect to mount a new strobe system in late 2011 or early 2012 on Sentry, and have indicated that the entire outcrop can be visually surveyed in about seven days of operation (includes battery recharging, etc) at an elevation of 5 m with this new strobe system. It may not be necessary to image the entire outcrop, but we will focus photo-mosaic operations on sites of interest for closer evaluation, and run repeat surveys at multiple altitudes to define better the distribution and size of water column anomalies.

            Jason II deployments will be guided using the initial bathymetric map and data collected with Sentry to locate and sample springs and hydrothermal plumes at/near the seafloor, and to conduct heat flow and sediment push core surveys on sedimented areas on Dorado outcrop and along the outcrop edge. Sentry and Jason II can work concurrently provided they are 300 m apart. Thus, after the initial day of mapping with Sentry, 6 days of bottom time (8 operating days) with Jason II are required to conduct six radial heat flow surveys along transects defined by the sub-bottom sonar and bathymetric data (each measurement takes 0.5 hours with 1.5 hours to take a push core, transit and set-up for the next measurement. Twelve measurements will be made on each survey, with transects oriented radially away from the edge of the outcrop). The combination of sediment pore water and heat flow data will allow quantification of hydrothermal fluxes, as described above. Four additional days of bottom time (6 operating days) are needed to sample springs using inverted funnels, barrels, or short “pipes” [e.g., Johnson et al., 2003] that minimize entrainment of bottom seawater during sampling.

            In aggregate, we can complete outcrop-wide mapping, water column surveys, sonar data acquisition, heat flow measurements, and seafloor sampling in 18 days on site, including one day for the initial map, eight days to conduct heat flow transects, six days to sample springs, one day for CTD operations to collect additional fluid samples near the seafloor, one day for vehicle timing (coordinating vehicles in/out of water) and maintenance, and one day for weather/contingency.

In summary

Sentry - will map Dorado Outcrop and possibly another nearby oucrop (Bathymetry, eH, temperature anomaly, chirp sonar, and likely photo mosaic

Jason - will conduct heat flow and push core surveys. When springs are found we will collect spring fluids, rocks, mats, clams (if any).  The springs should be 10 to 20 C.

Pre-cruise planning meeting: Teleconference

Stations:

  TicoFlux Outcrop area 8-10 N and 86 to 88 W
  Distance: null
  Days: null
  Latitude:
  Longitude:

  Tengosed Outcrop
  Distance: 10
  Days: 2
  Latitude: 9° 10.0’ N
  Longitude: 87° 0.0’ W

  Tico Flux Outcrops and Seamounts
  Distance: 20
  Days: 3
  Latitude: 9° N
  Longitude: 87° W

  ODP Hole 1255A
  Distance: 1
  Days: 1.5
  Latitude: 9° 39.272’ N
  Longitude: 86° 11.149’ W

  ODP Hole 1253A
  Distance: 50
  Days: 1.5
  Latitude: 9° 38.858’ N
  Longitude: 86° 11.434’ W

  Dorado Outcrop
  Distance: 100
  Days: 10
  Latitude: 87° 7.0’ N
  Longitude: 9° 5.0’ W

Funding Agency: NSF #1130146

- added NSF #1130146 on Aug 6, 2013 6:13 PM by
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R/V Atlantis

Shipboard Equipment

Bathymetry System 12 kHz
Sippican XBT System (Mark 21)
Deionized Water System
Relay Transponder for Wire Use
12 kHz Pinger for Wire Use
Transponder Navigation - Sonardyne USBL
Navigation - Heading
Multibeam
Fume Hood
Navigation - Position

Shipboard Communication

Basic Internet access via HiSeasNet

CTD/Water Sampling

911+ Rosette 24-position, 10-liter bottle Rosette with dual T/C sensors
SBE43 oxygen sensor
Wet Labs C*Star transmissometer (660nm wavelength)

Critical CTD Sensors: 

Sample Storage

Climate Controlled Walk-in
Freezer -70°C 25 cu. ft.
Freezer -70°C 3.2 cu. ft. ea.
Refrigerator 8.6 cu. ft.


Storage Notes: We will probably want both walk in refirgoration units  at 4degrees C.  Often one is at 4C and the other at -20C.  We will probably want both set to 4C

Navigation

Will you be using Long Base Line (LBL) navigation? no

Will you be using Ultra-short baseline (USBL) navigation for other than Alvin operations? no

Navigation

GPS
USBL

Navigation Notes: We need navigation for Jason, Sentry, adn for elevators.  Note that depths of the CORKS are ~4500m

Winches

CTD Winch with .322" Electro-mechanical wire
Trawl Winch with .681 fiber optic

Winch Notes: We will conduct a few CTDs and need the fiber wire for Jason II

Wire use and application

Trawl Winch with .681 fiber optic
CTD Winch with .322" Electro-mechanical wire


Wire Notes: We will conduct a few CTDs and need the fiber wire for Jason II

Slip ring required? no	Number of conductors:
Non-standard wire required? no	Type:
Traction winch required? no	Describe:

Portable Vans

Chemical Storage Van
Isotope Van

Other Science Vans:

Specialized Deck Equipment

Mooring Deployment/Recovery Equipment Required: no	Type:
Cruise Specific Science Winch Required: no	Type:
Nets Required: no	Type:

Over the Side Equipment

Will you be bringing any equipment (winches, blocks, etc.) that lowers instruments over the side? yes

Details: We should discuss teh Plasma winch, but I do not think that we will need it.

Special Requirements

Elecrical Power: no	Identify:
Equipment Handling: no	Identify:
Inter/intraship Communications: no	Identify:
Science Stowage: no	Identify:
Water: no	Identify:

Additional Cruise Items/Activities

Explosive Devices: no Portable Air Compressors: no Flammable Gases: no

Small Boat Operations: no SCUBA Diving Operations: no

Hazardous Material

Will hazardous material be utilized? yes

Radioactive Material

Radioiosotopes: no

Additional Information

Is night time work anticipated on this cruise? no

Specialized tech support (Seabeam, coring, other): 

Other required equipment and special needs: 

AUV Sentry

Site Survey

Will you provide detailed charts of the work area(s)?  yes
Current Chart(s):


If no, will you need Sentry to generate maps of the work area(s)?  yes

Will you need post-dive maps of the work area generated?  no

Navigation

Will you be using Long Base Line (LBL) navigation? no

Will you be using Ultra-short baseline (USBL) navigation? yes

Will you be using Doppler/GPS navigation? yes

Sensors & Samplers

Large capacity slurp samplers (Multi-chamber)
Scoop nets
What type of samples do you expect to collect?
fluids, sediment (push cores), heat flow, rocks (bio box). clams, chimney?, flow meter 9we will bring)

Science Supplied Equipment

Are you supplying equipment to be used with AUV Sentry?  no

Has this equipment been used on Sentry before?  no

Please give a brief description of the equipment, its intended purpose, the cruise # it was last used on if any and its deployment method.

Does this equipment use an external pressure housing?  no

Has the pressure case been tested to the anticipated depth of deployment?  no

Air weight(s) of this equipment?

Water weight(s) of this equipment?

Does the equipment require data or a power interface from the vehicle?
  no

Does the equipment meet the electrical requirements of the Sentry User Manual?  no

Additional Information

Brief operations description or comments: The plan is to have jason II on the seafloor at all times and send down push cores, fluid samplers, and bio boxes as needed. Also Sentry will be "mowing the lawn" while Jason is on the seafloor.  We will ahve daily meetings at noon to lay out the plan for the follong day based oon elevator and sentry needs.

Then we will go to the CORKS to download pressure data, recover an instrument sting, seal up the borehole witht he instruemnt string, collect fluids and monitor flow rate.

ROV Jason

Site Survey

Will you provide detailed charts of the work area(s)?  yes
Current Chart(s):


If no, willl you need Jason to generate maps of the work area(s)?  no

Will you need post-dive maps of the work area generated?  no

Navigation

Will you be using Long Base Line (LBL) navigation? no

Will you be using Ultra-short baseline (USBL) navigation? yes

Will you be using Doppler/GPS navigation? no

Sensors & Samplers

Large capacity slurp samplers (Multi-chamber)
Major water sampler(s)
Push corers
Scoop nets
Search Sonar
What type of samples do you expect to collect?
We want the low temperature probe is you have one.

Elevators

Will you be using elevators to transport samples to the surface?  yes

If yes, how many would you anticipate?  10

Cameras & Video

Video & Photo data

Science Supplied Equipment

Are you supplying equipment to be used on HOV Jason?
yes

Has this equipment been used on Jason before?  yes

Please give a brief description of the equipment, its intended purpose, the cruise # it was last used on if any and its deployment method.
Heat flow probe
CORK pressure download connector
Flow meter LED communicator

Does this equipment use an external pressure housing?  yes

If yes, what is the pressure rating? 
and test pressure? 

Or has the pressure case been tested per Alvin Pressure Test requirements?  yes

Housing schematic with dimensions and include air and water weights.

Does the equipment have an associated computer or control panel for remote operation from the personnel sphere?  yes

Air weight of this equipment?  10

Water weight of this equipment? 

Does the equipment require data or a power interface from the vehicle?  yes

Does this equipment require hydraulic inputs from the vehicle?  no
Hydraulic schematic of the equipment requirements.

Does this equipment require manipulation?  yes

If yes, please describe how the equipment is to be manipulated.
Heat flow probe was using on the Fisher 2013 cruise
CORK pressure downloads are common
The only new thing is a flow meter.  If we can get it to work it will either be a stand alone item that you pu in a vent or it will ahve a blue LED (Tivey et al - style) communicator

Will this equipment be deployed off the vehicle?  yes

If yes, please describe how the equipment is intended for deployment.

If yes, will the equipment be disconnected from the vehicle and left in situ?  no

How long will the deployment be? 

Will the equipment be recovered by the same vehicle?  no

If recovering equipment deployed with another vehicle, provide pressure rating: 
and test pressure: 

Does this equipment use any glass spheres for either buoyancy or as pressure housings?  no

Hazardous Material

Will hazardous material be utilized? no

Additional Information

Brief operations description or comments:

Date Submitted: Aug 6, 2013 6:38 PM