Dataset: X-ray diffraction from seafloor sulfide deposits East Pacific Rise 9-10 North
Deployment: AT42-09

x-ray diffraction, East Pacific Rise 2019

View Data: For data, See Dataset Metadata Page: https://www.bco-dmo.org/dataset/937020

Co-Principal Investigator:

Brandy Marie Toner (University of Minnesota Twin Cities, UMTC)

Scientist:

Rose Jones (University of Minnesota Twin Cities, UMTC)

Contact:

Rose Jones (University of Minnesota Twin Cities, UMTC)

BCO-DMO Data Manager:

Karen Soenen (Woods Hole Oceanographic Institution, WHOI BCO-DMO)

Project:

Collaborative Research: From hot to cold in the dark - shifts in seafloor massive sulfide microbial communities as physical and geochemical conditions change after venting ceases (Hot2cold Vents)

Version:

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Description

File naming:

Sample name (e.g. ALV5015_01_R01b)/sample name noted at time of data collection if incorrectly noted at that time (e.g. 5015_01_R01b)_sub-map name where there is one (A, a, b, B etc.)_where p occurs, refers to point collected within a sample_KeV, where it occurs is beam energy information_other annotations e.g. full_real come from beamline scientists, left in the file name to keep file name as original as possible_number generated by beamline software at time of collection

Methods & Sampling

Dataset acquisition description

Synchrotron micro-probe X-ray diffraction data were collected for seafloor sulfide deposits. Seafloor sulfide mineral samples were collected from hydrothermally active chimneys and inactive off-axis massive sulfide deposits at East Pacific Rise (EPR) 9.50°N in 2019-2021 on cruises AT42-09. Samples were collected using the HOV Alvin.

Samples were placed in a positive-pressure glove bag flushed with N2 (g), sparged with N2, heat-sealed into mylar bags containing Anaeropaks, and stored at -20°C. Epoxy embedded petrographic thin sections were created using these samples. Subsamples were dried for 24 hours under N2 (g), vacuum embedded in epoxy resin (Struers EpoFix Resin, 1L kit: Part #40200030) following manufacturer’s guidelines, and cured under N2 (g) for 24 hours. Each epoxy-embedded sample was pre-cut using a wafering saw then sent to Spectrum Petrographics, Inc. (Washington, USA) for preparation as 30 micron thick, double-polished thin sections mounted on quartz slides using methods to limit sample exposure to water and ambient air. When not in use, thin-sections were stored under N2 (g) to limit oxidation.

Thin sections were analyzed for X-ray diffraction at the X-ray Fluorescence Microprobe beamline "XFM", National Synchrotron Light Source II (NSLS II), Brookhaven National Laboratory, NY. X-ray diffraction patterns were collected from thin sections at XFM in transmission mode using a Perkin Elmer 1621 detector at 18 KeV (λ = 0.688801 Å) incident energy with a 60 s exposure time and 5 x 5µm spot size.

Data Processing Description

Dataset Processing Description

All data processing was done in software Dioptas (Prescher and Prakapenka 2015). The central beam stop was masked and substrate background subtracted. Diffraction patterns were radially integrated to obtain profiles of intensity verses 2θ.

More information about this dataset deployment

Funding

Award Number	Funding Source
OCE-1756339	NSF Division of Ocean Sciences
OCE-1756419	NSF Division of Ocean Sciences
OCE-1756558	NSF Division of Ocean Sciences

Instruments

HOV Alvin

Supplied Name:

Supplied Description:

Instrument Type

Generic Name: HOV Alvin

Generic Description:

Human Occupied Vehicle (HOV) Alvin is part of the National Deep Submergence Facility (NDSF). Alvin enables in-situ data collection and observation by two scientists to depths reaching 6,500 meters, during dives lasting up to ten hours.

Commissioned in 1964 as one of the world’s first deep-ocean submersibles, Alvin has remained state-of-the-art as a result of numerous overhauls and upgrades made over its lifetime. The most recent upgrades, begun in 2011 and completed in 2021, saw the installation of a new, larger personnel sphere with a more ergonomic interior; improved visibility and overlapping fields of view; longer bottoms times; new lighting and high-definition imaging systems; improved sensors, data acquisition and download speed. It also doubled the science basket payload, and improved the command-and-control system allowing greater speed, range and maneuverability.

With seven reversible thrusters, it can hover in the water, maneuver over rugged topography, or rest on the sea floor. It can collect data throughout the water column, produce a variety of maps and perform photographic surveys. Alvin also has two robotic arms that can manipulate instruments, obtain samples, and its basket can be reconfigured daily based on the needs of the upcoming dive.

Alvin's depth rating of 6,500m gives researchers in-person access to 99% of the ocean floor. Alvin is a proven and reliable platform capable of diving for up to 30 days in a row before requiring a single scheduled maintenance day. Recent collaborations with autonomous vehicles such as Sentry have proven extremely beneficial, allowing PIs to visit promising sites to collect samples and data in person within hours of their being discovered, and UNOLs driven technological advances have improved the ability for scientific outreach and collaboration via telepresence

Alvin is named for Allyn Vine, a WHOI engineer and geophysicist who helped pioneer deep submergence research and technology.

(from https://www.whoi.edu/what-we-do/explore/underwater-vehicles/hov-alvin/, accessed 2022-09-09)

Parameters

Supplied Name	Supplied description	Supplied Units	Standard Name
Cruise	Cruise ID (AT42-09)	unitless	cruiseid
File_name	file name	unitless	file_name
Sample_name	Sample name	unitless	sample
Time	T0	unitless	sample_descrip
Hydrotherml_vent_category	Type 1, 3 or 4	unitless	sample_descrip
Location	Mosh Pit, M Vent area, Bio9	unitless	site
Lat_dd	Sampling latitude	decimal degrees	lat
Lon_dd	Sampling longitude	decimal degrees	lon
Depth_mbs	Sample depth below seafloor	meter below seafloor (mbs)	depth
Hdg	Heading of vehicle at time of collection	degrees	heading
Date_collected	Collection date in ISO format	unitless	date
Time_collected	Collection time in ISO format	unitless	time
ISO_DateTime_UTC	Collection DateTime in ISO format (UTC timezone)	unitless	ISO_DateTime_UTC

Database

Contribute Data

Dataset: X-ray diffraction from seafloor sulfide deposits East Pacific Rise 9-10 North
Deployment: AT42-09

Dataset acquisition description

Dataset Processing Description

Database

Contribute Data

Dataset: X-ray diffraction from seafloor sulfide deposits East Pacific Rise 9-10 NorthDeployment: AT42-09

Dataset acquisition description

Dataset Processing Description

Dataset: X-ray diffraction from seafloor sulfide deposits East Pacific Rise 9-10 North
Deployment: AT42-09