Diving to an Underwater Volcano – NSF Cruise AT26-17A, Alvin Dive

“Under the sea, it seems my every gaze is as stolen from some forbidden world; and it triggers an emotional shock that never flags…”

Jacques-Yves Cousteau, 1976

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Alvin Dive Log: 4742
Date: 22 July, 2014
Dive time: 08:00
Dive Depth: ~1550m

Pilot: Bob Waters
Port Observer: Eric Mittelstaedt
Starboard Observer: Cody Youngbull

Location: ASHES Vent Field
Lat: 45.933299
Lon: -130.013682

Original Dive Objectives:
This dive’s primary objective is to deploy the VentCam and the Diffuse Effluent Monitoring System (DEMS) camera at the phoenix vent site and to recover the device that Bill and Kang deployed on dive 4741. Secondary objectives of this dive include taking 5L of bottom water using the small Niskin system, deploying a portable dot pattern screen analog of DEMS, and recovering one coated High Temperature HOBO from the Inferno vent. Tertiary objectives of this dive are to collect rock samples.

Accomplished Objectives on this Dive:
All objectives accomplished. The VentCam was successfully deployed, targeted onto phoenix vent focused flow, and confirmed to be operational. The DEMS camera system was successfully deployed, positioned over phoenix vent diffuse flow, and confirmed to be operational. The portable dot pattern screen was deployed, imaged and recovered. 5L of bottom water were sampled with the Niskin system at various locations. The coated High-Temperature HOBO probe was recovered from inferno vent. Rock samples were collected from regions of recent (2011 eruption) flow and old lava flow.

Dive Log (GMT time)
14:59 hatch sealed
15:04 alvin in water
15:08 swimmers clear, commencing dive
15:12 70 meters depth
15:20 passing through layer of bio-luminescent Cnidaria (jelly fish and siphonophores)
15:51 300 meters off bottom
16:00 100 meters off bottom
16:13 bottom sighted
16:15 approaching southeast landing zone
16:18 commencing to homer beacon
16:24 sheet flow formation noted for future drop sites
16:30 VentCam sighted at drop zone. move to approach.

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16:35 moving VentCam weights into Alvin basket to compensate weight
16:38 repositioning Alvin to acquire VentCam
16:39 VentCam retrieved (small foot stuck in basalt lost)
16:41 releasing water to compensate weight for ascent to 10 meters off bottom
16:48 10 meters off bottom. proceeding to phoenix vent 200 meters from current location
17:05 diffuse flow sighted. hydrothermal activity off port
17:06 markers #73 and #74 identified. confirmed we are at phoenix vent. white bacterial mats.
17:09 placing VentCam
17:11 VentCam on bottom. moving to position VentCam on phoenix vent focused flow
17:14:14 good video of coated HT HOBO & auxiliary structure
17:18:20 lens cap removed from VentCam. waiting for confirmation of VentCam function. laser
emission confirms, VentCam is operational.
17:25 Collecting Niskin #1. awaiting confirmation from ship on VentCam alignment.
17:31 leaving phoenix vent to retrieve DEMS from drop site
17:37 40 meters from DEMS drop site
17:38 DEMS sighted on port
17:42 DEMS grasped. Releasing water to lift off bottom
17:45 moving to collect souvenir rocks
17:46 rock sample #1. Folds of sheet flow at DEMS landing site.
17:49 souvenir rock grab complete. moving water onboard. proceeding to return to phoenix vent site
18:00 verified that DEMS illuminates during transit
18:06 positioning DEMS on phoenix vent diffuse flow
18:07 moving water onboard to compensate weight
18:12 rotating DEMS camera 180degrees to position properly on site
18:19 DEMS positioned. pulling pin on DEMS to commence leveling. pin retrieved to basket leg
18:22 DEMS camera leveled
18:24:00 rotating to check VentCam and confirm illumination
18:28:39 good views of VentCam. waiting to confirm strobe operations
18:30 verified VentCam lights come on.
18:35 placing Portable Random Dot Pattern.
18:39:22 picture of Portable Dot Pattern crush.
18:34 high zoom of Portable Dot Pattern with starboard brow cam
18:46:30 video of Portable Dot Pattern
18:51:49 camera removed from Portable Dot Cam
18:55:33 reading temperature on lower portion of Portable Dot Pattern
18:59:12 reading temperature on upper portion of Portable Dot Pattern
19:01:58 ceasing temperature reads
19:02:26 removing Portable Dot Pattern from sea floor and retrieving to basket
19:06:44 collecting Niskin #2 water sample atop diffuse flow at phoenix
19:08:17 leaving phoenix. Heading to Inferno for HT HOBO retrieval.
19:12 arrived at inferno vent
19:12:42 Coated HT-HOBO #7 Retrieved from cone
19:15:17 proceeding move to golem vent
19:16:35 collecting Niskin #3. Proceeding to Marker #21 for Kang’s instrument from golem vent
19:20:30 imaging Kang’s instrument on golem vent
19:21:44 Limpit growth on Kang’s instrument
19:25:20 retrieved Kang’s instrument to basket
19:26:40 leaving golem vent. heading to examine phoenix vent and to check DEMS and VentCam
19:30 returned back at phoenix vent and confirmed VentCam and DEMS are operational
19:31:40 Niskin #4 collected at phoenix vent
19:32:15 circling phoenix to capture video of VentCam and DEMS in operation
19:34:02 both VentCam and DEMS in field of view on starboard brow camera

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20:00:00 recording both VentCam and DEMS illuminating simultaneously. odd pulse observed on
VentCam
20:07:05 Niskin #5 collection. moving to caldera wall
20:09:51 arrived at wall. proceeding up wall to retrieve rock sample for Dan Fornari
20:15:00 retrieving rock sample #2 from 12 meters up on caldera wall from base. bowling ball shaped
rock sample imaged.
20:18:23 all objectives accomplished transiting to Ashes south east landing zone
20:38:50 after speaking topside we’ve changed plans and are now heading to region of new flow for
additional rock collection
20:42 following large white skate

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20:48:50 retrieving rock from flow boundary. new flow pillow basalt crust rock sample collection
20:50:00 focus on rock sample #3 from 2011 flow
20:56:00 imaging rock sample #4. may not in fact be old flow given the amount of glass present?
moving to more confirmed old flow site
20:58:21 at site of old flow. retrieving rock. very brittle. having difficulty.
21:07:14 finally got rock sample #5 from old sheet flow
21:08:46 rock sample #5 imaged and placed in basket. proceeding move to region of new flow.
21:24 transiting west to region of old flow
21:26:34 retrieving rock sample #6 from old flow
21:27:14 imaging rock sample #6
21:28 moving south 100 meters
21:37 field of yellow bacteria clumps. retrieving rock sample #7 from this location.
21:38:50 proceeding move onto site of new flow
21:44:32 attempt a final rock collection. failing in attempt.
21:47:43 battery low. moving to departure zone.
21:50 permission to surface granted. dropping weight. heading up.

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