Concentrations of gas dissolved in seawater and in gas bubbles collected in the northern Gulf of Mexico, April 12-20, 2015

Gulf of Mexico Integrated Spill Response Consortium (GISR)

DOI:
10.7266/N7610XXW
 
UDI:
R1.x137.000:0025
Last Update:
May 02 2018 19:30 UTC
 
Dataset Author(s):
John Kessler, Mihai Leonte
Point of Contact:
Kessler, John
University of Rochester / Department of Earth and Environmental Sciences
210 Hutchison Hall
Rochester, New York  14627
USA
john.kessler@rochester.edu
Funding Source:
RFP-I
Data Collection Period:
2015-04-12 to 2015-04-20

Identified Submitted In-Review Available
3 3 3 3

Suggested Citation:

John Kessler, Mihai Leonte (2018) Concentrations of gas dissolved in seawater and in gas bubbles collected in the northern Gulf of Mexico, April 12-20, 2015. Distributed by: Gulf of Mexico Research Initiative Information and Data Cooperative (GRIIDC), Harte Research Institute, Texas A&M University-Corpus Christi. doi:10.7266/N7610XXW

Abstract:

Seawater and gas samples were collected in the Gulf of Mexico at MC118, located at 28° 51.129’N, 88° 29.51’W, from 12 - 20 April 2015 aboard the E/V Nautilus. The seawater samples were collected directly from waters impacted by seafloor methane seeps. This was carried out using the SUPR sampler [Breier et al., 2014] mounted to the ROV Hercules. The SUPR sampler is an in-situ seawater pumping system and was developed to sample dynamic, high gradient, ocean geochemical features at areas such as seep sites. The inlet of the SUPR sampler was attached with tubing to the ROV arm and is pumped seawater directly into sampling bottles mounted to the ROV chassis. The samples were taken from waters visibly impacted by methane bubbles, so an adapter was placed on the inlet of the sampling tube to collect seawater but not bubbles. The seawater samples were measured for temperature and salinity, the concentrations of dissolved oxygen, methane, ethane, propane, and butane, as well as the stable carbon isotopes of methane (δ13C-CH4). The measurements of temperature, salinity, and dissolved oxygen were measured in-situ with probes mounted to the ROV; a Seabird FastCat 49Plus was used for the temperature and salinity measurements, while an Aanderaa Oxygen Optode 3830 was used for the dissolved oxygen measurements. Measurements of dissolved methane, ethane, propane, and n-butane concentrations were conducted on recovered samples while at sea on the E/V Nautilus. Samples for the analysis of δ13C-CH4 were preserved for later analysis in a land-based laboratory. The procedures for dissolved methane, ethane, propane, and butane concentrations as well as δ13C-CH4 are previously published [Leonte et al., 2017] and are being updated, focusing more specifically on the analyses of these samples [Leonte et al., 2018]. Samples of gas bubbles were collected using a custom built gas sampler made up of two plastic cylinders and a funnel. A primary cylinder was open at the bottom with a funnel attached underneath it to increase the surface area over which gas bubbles were collected. The primary cylinder and secondary cylinder were connected by a tube attached to the top of each cylinder. The secondary cylinder also had a drain tube attached to the bottom. Gas samples were collected by positioning the ROV within the bubble plume and using the funnel to direct gas bubbles into the primary cylinder. As the ROV ascended to be brought back on board, decreasing water pressure allowed the gas sample in the primary cylinder to expand into the secondary cylinder, driving out water through the drain tube. By the time the ROV was recovered, minimal water remained inside the secondary container. The collected gas samples were analyzed on shore for the mole percentages of Nitrogen, Methane, Carbon Dioxide, Ethane, Propane, Iso-Butane, n-Butane, Neopentane, Iso-Pentane, and n-Pentane using mass spectrometry analysis at the Woods Hole Oceanographic Institution. The specific procedures for the collection and analysis of these gas samples are being prepared for publication [Leonte et al., 2018]. Parts of this dataset have been converted to more accurately represent values found in the northern Gulf of Mexico. Those converted values can be found here. https://data.gulfresearchinitiative.org/data/R1.x137.000:0028.

Purpose:

This dataset was collected as part of a larger study to determine the fate of methane and other hydrocarbons following seafloor release from oil and gas seeps in the northern Gulf of Mexico.

Theme Keywords:

MC118, Gas Bubbles, Isotopes

File Format:

csv, pdf

Filename:

R1.x137.000-0025_BubbleData.zip (42.5 KB)

Dataset Downloads:

11

Concentrations of gas dissolved in seawater and in gas bubbles collected in the northern Gulf of Mexico, April 12-20, 2015



Identification Information
Distribution Information
Metadata Maintenance Information

Metadata: 
  File identifier: 
      R1.x137.000-0025-metadata.xml
  Language: 
      eng; USA
  Character set: 
    Character set code: 
      utf8
  Hierarchy level: 
    Scope code: 
      dataset
  Metadata author: 
    Responsible party: 
      Individual name: 
          John Kessler
      Organisation name: 
          University of Rochester / Department of Earth and Environmental Sciences
      Position name: 
          Associate Professor
      Contact info: 
        Contact: 
          Phone: 
            Telephone: 
              Voice: 
                  5852734572
              Facsimile: 
          Address: 
            Address: 
              Delivery point: 
                  210 Hutchison Hall
              City: 
                  Rochester
              Administrative area: 
                  New York
              Postal code: 
                  14627
              Country: 
                  USA
              Electronic mail address: 
                  john.kessler@rochester.edu
      Role: 
        Role code: 
          pointOfContact
  Date stamp: 
      2018-09-26T16:38:34+00:00
  Metadata standard name: 
      ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data
  Metadata standard version: 
      ISO 19115-2:2009(E)
  Dataset URI: 
      https://data.gulfresearchinitiative.org/metadata/R1.x137.000:0025
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Identification info: Data identification: Citation: Citation: Title: Concentrations of gas dissolved in seawater and in gas bubbles collected in the northern Gulf of Mexico, April 12-20, 2015 Alternate title: Date: Date: Date: 2018-05-02 Date type: Date type code: publication Abstract: Seawater and gas samples were collected in the Gulf of Mexico at MC118, located at 28° 51.129’N, 88° 29.51’W, from 12 - 20 April 2015 aboard the E/V Nautilus. The seawater samples were collected directly from waters impacted by seafloor methane seeps. This was carried out using the SUPR sampler [Breier et al., 2014] mounted to the ROV Hercules. The SUPR sampler is an in-situ seawater pumping system and was developed to sample dynamic, high gradient, ocean geochemical features at areas such as seep sites. The inlet of the SUPR sampler was attached with tubing to the ROV arm and is pumped seawater directly into sampling bottles mounted to the ROV chassis. The samples were taken from waters visibly impacted by methane bubbles, so an adapter was placed on the inlet of the sampling tube to collect seawater but not bubbles. The seawater samples were measured for temperature and salinity, the concentrations of dissolved oxygen, methane, ethane, propane, and butane, as well as the stable carbon isotopes of methane (δ13C-CH4). The measurements of temperature, salinity, and dissolved oxygen were measured in-situ with probes mounted to the ROV; a Seabird FastCat 49Plus was used for the temperature and salinity measurements, while an Aanderaa Oxygen Optode 3830 was used for the dissolved oxygen measurements. Measurements of dissolved methane, ethane, propane, and n-butane concentrations were conducted on recovered samples while at sea on the E/V Nautilus. Samples for the analysis of δ13C-CH4 were preserved for later analysis in a land-based laboratory. The procedures for dissolved methane, ethane, propane, and butane concentrations as well as δ13C-CH4 are previously published [Leonte et al., 2017] and are being updated, focusing more specifically on the analyses of these samples [Leonte et al., 2018]. Samples of gas bubbles were collected using a custom built gas sampler made up of two plastic cylinders and a funnel. A primary cylinder was open at the bottom with a funnel attached underneath it to increase the surface area over which gas bubbles were collected. The primary cylinder and secondary cylinder were connected by a tube attached to the top of each cylinder. The secondary cylinder also had a drain tube attached to the bottom. Gas samples were collected by positioning the ROV within the bubble plume and using the funnel to direct gas bubbles into the primary cylinder. As the ROV ascended to be brought back on board, decreasing water pressure allowed the gas sample in the primary cylinder to expand into the secondary cylinder, driving out water through the drain tube. By the time the ROV was recovered, minimal water remained inside the secondary container. The collected gas samples were analyzed on shore for the mole percentages of Nitrogen, Methane, Carbon Dioxide, Ethane, Propane, Iso-Butane, n-Butane, Neopentane, Iso-Pentane, and n-Pentane using mass spectrometry analysis at the Woods Hole Oceanographic Institution. The specific procedures for the collection and analysis of these gas samples are being prepared for publication [Leonte et al., 2018]. Parts of this dataset have been converted to more accurately represent values found in the northern Gulf of Mexico. Those converted values can be found here. https://data.gulfresearchinitiative.org/data/R1.x137.000:0028. Purpose: This dataset was collected as part of a larger study to determine the fate of methane and other hydrocarbons following seafloor release from oil and gas seeps in the northern Gulf of Mexico. Status: Progress code: completed Point of contact: Responsible party: Individual name: John Kessler Organisation name: University of Rochester / Department of Earth and Environmental Sciences Position name: Associate Professor Contact info: Contact: Phone: Telephone: Voice: 5852734572 Facsimile: Address: Address: Delivery point: 210 Hutchison Hall City: Rochester Administrative area: New York Postal code: 14627 Country: USA Electronic mail address: john.kessler@rochester.edu Role: Role code: pointOfContact Descriptive keywords: Keywords: Keyword: MC118 Keyword: Gas Bubbles Keyword: Isotopes Type: Keyword type code: theme Descriptive keywords: Keywords: Keyword: northern Gulf of Mexico Type: Keyword type code: place Language: eng; USA Topic category: Topic category code: oceans Extent: Extent: Geographic element: Geographic bounding box: West bound longitude: -88.4918 East bound longitude: -88.4918 South bound latitude: 28.85215 North bound latitude: 28.85215 Geographic element: BoundingPolygon: Polygon: gml:MultiPoint: gml:pointMember: Point: gml:pos: 28.85215 -88.4918 Temporal element: Temporal extent: Extent: Time period: Description: ground condition Begin date: 2015-04-12 End date: 2015-04-20 Supplemental Information: Filename: MC118-Water.csv Variable Description Dive # The name of the dive where samples were collected Sample ID Unique sample number Date UTC Date when sample was collected in UTC time (MDDYYYY) Start time UTC The UTC time when sample collection began (HH:MM:SS) End Time UTC The UTC time when sample collection ended (HH:MM:SS) Depth (m) The depth in meters at which the sample was collected Altitude (m) The distance above the seafloor in meters where the samples were collected Temp (deg C) Water temperature when the sample was collected in degrees Celcius Salinity (ppt) Salinity when the sample was collected in parts per thousand Oxygen (umoles/L) Dissolved oxygen level while the sample was collected in units of micromoles per liter Latitude_N Latitude North in decimal degrees Longitude_W Longitude West in decimal degrees Methane (nM) The measured dissolved Methane concentration in units of nanomoles per liter Methane Stdev (nM) The standard deviation of the measured dissolved Methane concentration in units of nanomoles per liter Ethane (nM) The measured dissolved Ethane concentration in units of nanomoles per liter Ethane Stdev (nM) The standard deviation of the measured dissolved Ethane concentration in units of nanomoles per liter Propane (nM) The measured dissolved Propane concentration in units of nanomoles per liter Propane Stdev (nM) The standard deviation of the measured dissolved Propane concentration in units of nanomoles per liter Butane (nM) The measured dissolved n-Butane concentration in units of nanomoles per liter Butane Stdev (nM) The standard deviation of the measured dissolved n-Butane concentration in units of nanomoles per liter d13C-CH4 The natural stable carbon isotopic composition of dissolved Methane (δ13C-CH4) in units of per mille (‰) d13C-CH4 Stdev The standard deviation of the natural stable carbon isotopic composition of dissolved Methane (δ13C-CH4) in units of per mille (‰) Filename: MC118-Gas.csv Variable Description Dive # The name of the dive where samples were collected Sample ID Unique sample number Date UTC Date when sample was collected in UTC time (MDDYYYY) Start time UTC The UTC time when sample collection began (HH:MM:SS) End Time UTC The UTC time when sample collection ended (HH:MM:SS) Depth (m) The depth in meters at which the sample was collected Altitude (m) The distance above the seafloor in meters where the samples were collected Temp (deg C) Water temperature when the sample was collected in degrees Celsius Salinity (ppt) Salinity when the sample was collected in parts per thousand Oxygen (umoles/L) Dissolved oxygen level while the sample was collected in units of micromoles per liter Latitude_N Latitude North in decimal degrees Longitude_W Longitude West in decimal degrees Nitrogen The mole percentage of N2 gas in the sample. Nitrogen Stdev The standard deviation of the mole percentage of N2 gas in the sample. Methane The mole percentage of Methane gas in the sample. Methane Stdev The standard deviation of the mole percentage of Methane gas in the sample. Carbon Dioxide The mole percentage of Carbon Dioxide gas in the sample. Carbon Dioxide Stdev The standard deviation of the mole percentage of Carbon Dioxide gas in the sample. Ethane The mole percentage of Ethane gas in the sample. Ethane Stdev The standard deviation of the mole percentage of Ethane gas in the sample. Propane The mole percentage of Propane gas in the sample. Propane Stdev The standard deviation of the mole percentage of Propane gas in the sample. Iso-Butane The mole percentage of Iso-Butane gas in the sample. Iso-Butane Stdev The standard deviation of the mole percentage of Iso-Butane gas in the sample. n-Butane The mole percentage of n-Butane gas in the sample. n-Butane Stdev The standard deviation of the mole percentage of n-Butane gas in the sample. d13C-CH4 The natural stable carbon isotopic composition of dissolved Methane (δ13C-CH4) in units of per mille (‰) d13C-CH4 Stdev The standard deviation of the natural stable carbon isotopic composition of dissolved Methane (δ13C-CH4) in units of per mille (‰) The concentrations of Neopentane, Iso-Pentane, and n-Pentane were the below detection limit.|||||Breier, J., Sheik, C., Gomez-Ibanez, D., Sayre-McCord, R., Sanger, R., Rauch, C., Coleman, M., Bennett, S., Cron, B., Li, M., 2014. A large volume particulate and water multi-sampler with in situ preservation for microbial and biogeochemical studies. Deep Sea Research Part I: Oceanographic Research Papers 94, 195-206. doi:10.1016/j.dsr.2014.08.008 Leonte, M., Kessler, J.D., Kellermann, M.Y., Arrington, E.C., Valentine, D.L., Sylva, S.P., 2017. Rapid rates of aerobic methane oxidation at the feather edge of gas hydrate stability in the waters of Hudson Canyon, US Atlantic Margin. Geochimica et Cosmochimica Acta 204, 375-387. doi:10.1016/j.gca.2017.01.009 Leonte, M., Wang, B., Socolofsky, S.A., Breier, J.A., and Kessler, J.D., 2018. Using carbon isotope fractionation to constrain the extent of methane dissolution into the water column surrounding a natural hydrocarbon gas plume in the Northern Gulf of Mexico. In Preparation to be submitted to Geochemistry, Geophysics, Geosystems.
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Distribution info: Distribution: Distributor: Distributor: Distributor contact: Responsible party: Organisation name: Gulf of Mexico Research Initiative Information and Data Cooperative (GRIIDC) Contact info: Contact: Phone: Telephone: Voice: 3618253604 Address: Address: Delivery point: 6300 Ocean Drive City: Corpus Christi Administrative area: TX Postal code: 78412 Country: USA Electronic mail address: griidc@gomri.org Online Resource: Online Resource: Linkage: URL: https://data.gulfresearchinitiative.org Role: Role code: distributor Distributor format: Format: Name: csv, pdf Version: inapplicable File decompression technique: zip Distributor transfer options: Digital transfer options: Transfer size: 0.0425 Online: Online Resource: Linkage: URL: https://data.gulfresearchinitiative.org/data/R1.x137.000:0025 Protocol: https Name: Data Landing Page Description: GRIIDC dataset landing page Function: Online function code: information
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Metadata maintenance: Maintenance information: Maintenance and update frequency: unknown Maintenance note: This ISO metadata record was automatically generated from information provided to GRIIDC for dataset: R1.x137.000:0025 on 2019-11-19T17:02:03-06:00
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