Woods Hole Oceanographic Institution

Cruise Planning Synopsis

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AT37-08 Cheadle "Pito Deep Gabbros"


R/V Atlantis


AUV Sentry, ROV Jason

Cruise Party

Michael Cheadle: Chief Scientist, Principal Investigator
University of Wyoming 1000 E University Ave Laramie, Wyoming USA 82071
+1 307 721 5082

Jeffrey Gee: Principal Investigator
+1 858 534 4707

Barbara John: Principal Investigator
University of Wyoming P.O. BOX 3006 Laramie, WY USA 82071
+1 307 766 4232

Departure: Jan 14, 2017

Isla de Pascua (Easter Island)

Arrival: Feb 20, 2017

Arica- Chile

Operations Area

Pito Deep, NE corner of the Easter Microplate EPR
Lat/Lon: 22° 58.0′ S / 111° 57.0′ W
Depth Range: 2000m / 6000m
Will the vessel be operating within 200 NM of a foreign country? no

Science Objectives

i)   Map, using Sentry, the bathymetry & collect magnetic data along part of the north wall of Pito Deep in order to a) determine the vertical geometry of the magnetic polarity boundaries (stripes),  & b) determine locations for Jason II dives.

ii)   Conduct Jason traverses (& dredges- during Sentry dives if possible) on the north wall  to sample the upper part (1-2km?) of the gabbros that form ocean crust layer 3. The traverses will be spaced over a distance of ~20km allowing us to examine the lateral variation in layer 3 along a flowline & overall determine how ocean crust is accreted.

iii)   Explore for seafloor fluid flow during  Sentry dives; if feasible, prospect for fluid flow with water column sensors.

iv)  Dive with Jason II to sample any new fluid flow sites found in Pito Deep area

Visit the black smoker site on Pito Seamount (2200m), last visited by Nautile 23 years ago to photograph and sample rocks and possibly vent (micro)biological samples. This site is ~50km to the SE of the main work site. (Station 3- Pito Seamount)
Objectives iii, iv and v are secondary to objectives i & ii.

Science Activities

i)  Sentry surveys to collect bathymetric, side-scan, and high-resolution magnetic anomaly data, to identify sampling targets and map reversal boundaries. Sentry surveys will be conducted ~80m above bottom, with contour parallel lines and a nominal vertical spacing of 100m to allow complete bathymetric and side-scan coverage with the Reson 7125 system, and to permit gridding of the near-bottom magnetic anomaly data.  Approx 8-10 x 20hr dives.  Approx 4-5 dives at the start of the cruise. (Area B)  & 4-5 dives midway through the cruise (Area A). These Areas are very close to each other  (10nm)  See supporting figures.
 ii) The new Sentry surveys and all existing DSL-120 side-scan imagery and previous dive transects will be used to select locations for Jason II dives.  We expect sediment cover & mass wasting to be extensive, hence the need for as much information as possible to site the Jason dives. We envisage ~5 Jason dives/transects to photograph & sample the gabbros, spaced approximately 5km apart (from ~6km to 3.5km water depth- maximum possible range) over a distance of ~ 20km. (Areas B & A). Area B is likely to be the main target.
iii) Dredging of the gabbros during Sentry dives, if possible, or during downtime. (Areas B & A). Note, we understand efficiency is the key here & it might turn out that because of the winch issue for Jason & dredging & the difficulty of dredging during Sentry dives that dredging activities become a minor activity & in which case max. efficiency might involve inter-leaved Sentry & Jason dives.
iv) Explore for seafloor fluid flow using  Sentry equipped with available in situ water column sensors, sidescan  to prospect for fluid flow, during the Sentry dives if possible.   Assuming time is available, we would also plan to dive on new sites of fluid flow found within the cruise duration as part of the ongoing Jason dive program at Pito Deep.
v) At the end of the cruise, assuming time permits, we would like to carry out one Jason II dive  on a black smoker site on Pito Seamount (50km to the SE) last visited by Nautille in 1993 (Station 3- Pito Seamount). This site has never previously been sampled. We propose to collect rock samples & “voucher” (micro)-biological samples (collected by slurp sampler and/or bio-box then frozen aboard ship) to colleagues ashore. See supporting figure for location.
Note activities i to iii are the main priority of the cruise. Activities iv & v are ancillary activities to be scheduled as timing permits. 
Also, we would like to carry out dual Sentry & Jason II operations as much as possible given the water depths & logistical limitations.
Maps of areas B & A are attached 

Additional Info

Pre-cruise Planning Meeting: Teleconference
Meeting Notes: 3-way: Cheadle & John in Wyoming Gee at Scripps & WHOI
Media personnel on board: Video, Writer, Teacher
We have discussed (organized) extra bandwidth with Kevin Walsh (Scripps) HSN support. We have extra monies in the grant for this. We plan on taking 3 media/education folks & plan on carrying out some (2 per day?) 2-way ship to shore broadcasts to schools, societies etc. We intend to make videos, podcasts, blogs etc.


  Area B
  Distance: 279
  Days: 10
  Latitude: 23° 0.27’ S
  Longitude: 111° 54.219’ W

  Area A
  Distance: 10
  Days: 13
  Latitude: 22° 53.021’ S
  Longitude: 112° 3.595’ W

  Pito Seamount
  Distance: 36
  Days: 2
  Latitude: 23° 19.742’ S
  Longitude: 111° 38.709’ W

Supporting documentation:

Notes: BOXES - FOR CHEADLE from Dan F
These notes are from email messages:

here is a photo of the science hold with our 3 boxes left for you with the following
1) 1 gray tote with UF microscope and gloves & your 2 microscope lights
2) 1 cardboard box with the shank WHOI microscope
3) 1 large gray case with my 3 monitors (2 work and i have to mail you the dongles)

there will be a 4th box - gray plastic tote in that same place too with the expresso maker and 2 coffee pots,
grinder etc.

there is more coffee beans in with the monitors and #4 and #2 filters and filter holders and 1 grinder

2-Dec-2016 Mike Perfit email
A few notes: The UF binoc focus does not rachet to focus any longer but works by moving the oculars up and down with
the coarse adjustment.Read the instructions for the espresso maker, it’s a bit different than the one I have at home
in terms of “foaming”. It also has sizes for single and double shots.  we are leaving a number of pounds of beans
and also coffee “pods” that are an easy way to make espresso.

2-Dec-2016 email - Dan F
hi sharon OKi’ll put the MAPR case with the other boxes we are leaving for mike and bobbie in the science hold
(coffee makers, microscopes, lights, etc)

i’ll let allison SSSG know too and will mark the box - it is a black pelican case.


Funding Agency: NSF
Grant or contract number: 1459387
Funding Agency: NSF
Grant or contract number: 1459462

Scientific Instrumentation for R/V Atlantis

Shipboard Equipment

Towed Magnetometer
Navigation - Position
Transponder Navigation - Sonardyne USBL
12 kHz Pinger for Wire Use
Navigation - Heading
Relay Transponder for Wire Use
Bathymetry System 3.5 kHz

Shipboard Communication

Basic Internet access via HiSeasNet
Is there an expectation to use Skype or any other real-time video conference program?
Is there a need to transfer data to shore on a regular basis?

CTD/Water Sampling

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

Critical CTD Sensors

If the STM is not already High-Gain (same as on Sentry) then Chris German can bring his own (2)

Sediment Sampling

Rock dredges

Sample Storage

Freezer -70°C 25 cu. ft.
Freezer -70°C 3.2 cu. ft. ea.
Storage Notes: We would like the opportunity to collect voucher biological samples from Pito Seamount since that site has never been sampled previously.  Best practice for DNA analyses of samples (to be offloaded at cruise end and airshipped back to US) would be to freeze samples to -70C while at sea.


Will you be using Long Base Line (LBL) navigation? no
How many nets? null
How many tansponders? null
Will you be using Ultra-short baseline (USBL) navigation?no


Navigation Notes: We will require USBL for Sentry and Jason navigation.
Ideally, we would also like to attach a USBL beacon to the CTD so that if we find signals indicative of seafloor fluid flow, we know where those samples come from, at depth.


CTD Winch with .322" Electro-mechanical wire
Trawl Winch with 9/16th trawl wire
Winch Notes: a) CTD winch for CTD-rosette operations (vertical casts + Niskin sampling for methane analyses on ship using Jeff Seewald - WHOI MC&G's Gas Chrmatograph, operated by Sean Sylva (WHOI)

b) Trawl winch (presumably) for seafloor dredging - can WHOI provide Dredge Baskets etc?

Wire use and application

Trawl Winch with 9/16th trawl wire
Winch Notes:

Standard Oceanographic Cables

Slip ring required? no
Non-standard wire required? no
Traction winch required? no

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? no

Special Requirements

Elecrical Power: no Identify 
Equipment Handling: no Identify: 
Inter/intraship Communications: no Identify: 
Science Stowage: yes Identify: 8 Zarges boxes, 100-200 x 5 gallon sample buckets. & a mini boat (~ 5ft long)
Water: yes Identify: Small amounts of Milli-Q likely to be useful for lab work

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
Describe deployment method and quantity:
Sean Sylva (WHOI MC&G) will be operating a gas chromatograph aboard ship which requires use of compressed gases.  We will complete all necessary paperwork well ahead of the cruise, as required.

Radioactive Material


Additional Information

Is night time work anticipated on this cruise?yes
Specialized tech support (Seabeam, coring, other):
Dredging, Jason, Sentry
CTD casts will be conducted between Jason dives, whenever those opportunities arise.
These casts (up to 5h duration at 5000m depth) may be at night rather than in day time.
Other required equipment and special needs:
We plan to launch a 5ft long mini-boat/float for middle school kidz at some pt. during the cruise
Also, we will be carrying six Argo floats for James Gilson to launch periodically during the transit to Chile

We will also need the rock saws.  The one that is available on Atlantis & if necc. the 2nd one that will be travelling with the Gregg cruise. To save costs, we plan on sharing some equipment (microscopes etc.).

<Could not load the preview of ROV Jason Information data >

Scientific Instrumentation for AUV Sentry

Current Chart(s):

What type of samples do you expect to collect?None

Site Survey

Will you provide detailed charts of the work area(s)?no
If no, willl you need R/V Atlantis to generate maps of the work area(s)?no
Will you need post-dive maps of the work area generated?no


Will you be using Long Base Line (LBL) navigation? no
How many nets? null
How many tansponders? null
Will you be using Ultra-short baseline (USBL) navigation?no
Will you be using Doppler/GPS navigation? no

Science Supplied Equipment

Are you supplying equipment to be used on HOV AbeSentry yes
Has this equipment been used on AbeSentry 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.
J. Gee will supply a Cs magnetometer system and pressure case. This prototype sensor from Geometrics has two small (~1 cubic inch) sensors and will allow total magnetic field intensities to be measured without the need for calibration and may also yield short baseline gradiometry data. We have been in discussion with Carl Kaiser about the sensor mounting, data logging and requirements for the pressure case. The sensor will be delivered in mid Sept. and a pressure case is in design. Because of the length of the pressure case (~36”) we anticipate that pressure tests will be conducted at WHOI. The sensor package is currently under review for export control. We have initiated a license request in the event that the sensor will be subject to ITAR/EAR export control.
Does this equipment use an external pressure housing? yes
Has the pressure case been tested to the anticipated depth of deployment?& no
Pressure housing schematic with dimensions and include air and water weights.
Air weight of this equipment? 30
Water weight of this equipment? 10
Does the equipment require data or a power interface from the vehicle? yes
Does the equipment meet the electrical requirements of the Sentry User Manual? yes

Additional Information

Brief operations description or comments:
Primary objectives for Sentry will be seafloor geophysical surveys- bathymetry, sidescan & magnetics.
Secondary objectives will include seafloor fluid flow detection and bottom photography in any candidate fluid flow sites.

Checklist & Notes


U.S. Customs Form: no
Diplomatic Clearance: no
Date Submitted:
Date Approved:
Agent Information:
Isotope Use Approval: no
Isotope Notes:
SCUBA Diving: no


SSSG Tech: