The Sedimentological Characteristics and Radiochemistry Data for the Marshes on Dauphin Island, Alabama (U.S. Geological Survey Field Activity Number 2015-322-FA)

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What does this data set describe?

Title:
The Sedimentological Characteristics and Radiochemistry Data for the Marshes on Dauphin Island, Alabama (U.S. Geological Survey Field Activity Number 2015-322-FA)
Abstract:
This project is a collaborative effort between the U.S. Geological Survey (USGS), U.S. Army Corps of Engineers (USACE), and the state of Alabama funded by the National Fish and Wildlife Foundation (NFWF) to investigate viable, sustainable restoration options that protect and restore the natural resources of Dauphin Island, Alabama. Scientists from the USGS, St. Petersburg Coastal and Marine Science Center collected push cores and water quality data from the marshes of Dauphin Island, Little Dauphin Island, and Cedar Key, Alabama in August, 2015 (U.S. Geological Survey Field Activity Number (FAN) 2015-322-FA; referred to as 15BIM09) as well as in April, 2013 (13BIM01). Sample sites varied between high marshes, low salt marshes, and sand flats. This report serves as an archive for the sedimentological and geochemical data derived from the marsh cores and select surface data from the corresponding marsh core sites collected in August, 2015 (15BIM09). Downloadable data are available and include Excel spreadsheets, JPEG files, and formal Federal Geographic Data Committee metadata. For further information regarding data collection and/or processing methods refer to USGS OFR Ellis and others 2017–1165 (https://doi.org/10.3133/OFR20171165), and Data Series Ellis and others 2017–1046 (https://doi.org/10.3133/DS20171046).
Supplemental_Information:
To ensure that USGS-St. Petersburg data management protocols were followed, this survey was assigned the following USGS field activity number (FAN): 2015-322-FA (Project ID 15BIM09), additional survey and data details are available at https://cmgds.marine.usgs.gov/fan_info.php?fan=2015-322-FA. In August, 2015, USGS scientists collected eleven sediment push cores from ten unique sites on Dauphin Island, a barrier island in the northern Gulf of Mexico. The sample locations field setup consisted of a rover Global Positioning System (GPS) unit used to collect data at each sample site, and two base stations. Base stations were established approximately 11 kilometers (km) apart to ensure coverage throughout the island. During field sampling, shear vane measurements were collected at each site along with water parameter measurements, when possible, which are included in this report.
  1. How might this data set be cited?
    Ellis, Alisha M., Smith, Christopher G., and Marot, Marci E., 20170805, The Sedimentological Characteristics and Radiochemistry Data for the Marshes on Dauphin Island, Alabama (U.S. Geological Survey Field Activity Number 2015-322-FA): U.S. Geological Survey Data Release dos:10.5066/F7VM49J0, U.S. Geological Survey, St. Petersburg, FL.

    Online Links:

    This is part of the following larger work.

    Ellis, Alisha M., Smith, Christopher G., and Marot, Marci E., 20170805, The Sedimentological Characteristics and Geochronology of the Marshes of Dauphin Island, Alabama: U.S. Geological Survey Open-File Report ofr20171165, U.S. Geological Survey, St. Petersburg, FL.

    Online Links:

  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -88.13460
    East_Bounding_Coordinate: -88.10999
    North_Bounding_Coordinate: 30.27667
    South_Bounding_Coordinate: 30.25249
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
    Beginning_Date: 18-Aug-2015
    Ending_Date: 20-Aug-2015
    Currentness_Reference:
    Ground condition
  5. What is the general form of this data set?
    Geospatial_Data_Presentation_Form: Multimedia presentation
  6. How does the data set represent geographic features?
    1. How are geographic features stored in the data set?
      This is a Point data set.
    2. What coordinate system is used to represent geographic features?
      Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.0197876624. Longitudes are given to the nearest 0.0227845496. Latitude and longitude values are specified in Decimal degrees. The horizontal datum used is D_North_American_1983.
      The ellipsoid used is GRS_1980.
      The semi-major axis of the ellipsoid used is 6378137.0.
      The flattening of the ellipsoid used is 1/298.25722101.
  7. How does the data set describe geographic features?
    15BIM09-DA_M_Site_Information.xlsx
    Microsoft Excel workbook defining and describing the station locations at each sediment core site collected on Dauphin Island, Alabama (USGS FAN 2015-322-FA). (Source: USGS)
    15BIM09-DA_M_Site_Information.csv
    Comma-separated values text file defining and describing the station locations at each sediment core site collected on Dauphin Island, Alabama (USGS FAN 2015-322-FA). (Source: USGS)
    Core ID
    Core identifier assigned by USGS scientist. The following additional designations were also used: M, marsh push core; R, Russian peat auger; A, first core collected; B, second core collected at the same site. (Source: USGS) Character string
    Date Collected
    Date identifier (Source: USGS)
    Range of values
    Minimum:08/18/2015
    Maximum:08/20/2015
    Units:m/dd/yy
    Resolution:1 day
    Latitude (NAD83)
    Latitude of station location, in decimal degrees (North American Datum of 1983). (Source: USGS)
    Range of values
    Minimum:30.25249
    Maximum:30.27667
    Units:Decimal degrees
    Resolution:0.00001
    Longitude (NAD83)
    Longitude of site location, in decimal degrees (North American Datum of 1983). (Source: USGS)
    Range of values
    Minimum:-88.13459
    Maximum:-88.10999
    Units:Decimal degrees
    Resolution:0.00001
    Northing (WGS84) (m)
    The northward measured distance of the site location, in Cartesian coordinates (World Geodetic System of 1984) (meters). (Source: USGS)
    Range of values
    Minimum:390845.8
    Maximum:393234.2
    Units:meters
    Resolution:0.1
    Easting (WGS84) (m)
    The eastward measured distance of the site location, in Cartesian coordinates (World Geodetic System of 1984) (meters). (Source: USGS)
    Range of values
    Minimum:3347308.5
    Maximum:3349972.6
    Units:meters
    Resolution:0.1
    Elevation (NAVD88 G12A) (m)
    The elevation of each site relative to the North American Datum of 1988 Geoid 12A (in meters). (Source: USGS)
    Range of values
    Minimum:0.0963
    Maximum:0.2638
    Units:meters
    Resolution:0.0001
    Environment Type
    The type of environment the core was collected in. (Source: USGS) Character string
    Dominant Vegetation Type
    The type of vegetation present where the core was collected. (Source: USGS) Character string
    Approximate Push Core Length (cm)
    The approximate length of the push core collected, in centimeters, as recorded in the field. (Source: USGS)
    Range of values
    Minimum:34.0
    Maximum:74.0
    Units:centimeters
    Resolution:0.5
    Approximate Compaction of Push Core (cm)
    The approximate amount of compaction withstood by the core, in centimeters, as recorded in the field. (Source: USGS)
    Range of values
    Minimum:2.0
    Maximum:32.0
    Units:centimeters
    Resolution:0.5
    Number of 50 cm Auger Sections (N)
    The total number of 50 centimeter sections of Russian Peat Augers collected at each station. (Source: USGS)
    Range of values
    Minimum:1
    Maximum:3
    Units:number of 50 centimeter sections
    Resolution:1
    Approximate Auger Length (cm)
    The total length of the Russian Peat Auger collected at each station in centimeters, as recorded in the field. (Source: USGS)
    Range of values
    Minimum:50.0
    Maximum:150.0
    Units:centimeters
    Resolution:0.5
    15BIM09-DA_M_Water_Parameters.xlsx
    Microsoft Excel workbook defining water quality parameters at each sediment core site collected on Dauphin Island, Alabama (USGS FAN 2015-322-FA). (Source: YSI)
    15BIM09-DA_M_Water_Parameters.csv
    Comma-separated values text file defining water quality parameters at each sediment core site collected on Dauphin Island, Alabama (USGS FAN 2015-322-FA). (Source: YSI)
    Site ID
    Site identifier assigned by USGS scientist (Source: USGS) Character string
    Temperature (°C)
    Water temperature in degrees Celsius at each core location. (Source: YSI)
    Range of values
    Minimum:27.3
    Maximum:35.6
    Units:Degrees Celsius
    Resolution:0.1
    Pressure (mmHg)
    Barometric pressure in millimeters mercury at each core location. (Source: YSI)
    Range of values
    Minimum:762.0
    Maximum:763.9
    Units:Millimeters of mercury
    Resolution:0.1
    Dissolved Oxygen (%)
    Percent dissolved oxygen at each core location. (Source: YSI)
    Range of values
    Minimum:10.0
    Maximum:71.8
    Units:Percent
    Resolution:0.1
    Dissolved Oxygen (mg/L)
    Dissolved oxygen in milligrams per liter at each core location. (Source: YSI)
    Range of values
    Minimum:0.0
    Maximum:4.3
    Units:Milligrams per liter
    Resolution:0.1
    Specific Conductance (mS/cm)
    Specific conductance in millisiemens per centimeter at core location. (Source: YSI)
    Range of values
    Minimum:36.7
    Maximum:47.6
    Units:Millisiemens per centimeter
    Resolution:0.1
    Salinity
    Salinity at each core location. (Source: YSI)
    Range of values
    Minimum:23.0
    Maximum:31.0
    Units:Practical salinity units
    Resolution:0.1
    pH
    pH at each core location (Source: YSI)
    Range of values
    Minimum:6.3
    Maximum:7.2
    Units:Hydrogen ion concentrations
    Resolution:0.1
    pH (mV)
    pH in millivolts at each core location. (Source: YSI)
    Range of values
    Minimum:-10.2
    Maximum:42.0
    Units:Millivolts
    Resolution:0.1
    Oxidation-Reduction Potential (mV)
    Oxidation-reduction potential in millivolts at each core location. (Source: YSI)
    Range of values
    Minimum:-300.0
    Maximum:75.8
    Units:Millivolts
    Resolution:0.1
    15BIM09-DA_M_Sediment_Physical_Properties.xlsx
    Microsoft Excel workbook listing water content, porosity, bulk density and loss-on-ignition data for sediment cores collected on Dauphin Island, Alabama (USGS FAN 2015-322-FA). The results for each core are provided on its own tab. (Source: USGS)
    15BIM09-DA_M_Sediment_Physical_Properties.csv
    Comma-separated values text file listing water content, porosity, bulk density and loss-on-ignition data for sediment cores collected on Dauphin Island, Alabama (USGS FAN 2015-322-FA). (Source: USGS)
    Core ID
    Core identifier assigned by USGS scientist, M indicates the sample is a marsh push core. (Source: USGS) Character string
    Depth (cm)
    Depth interval in centimeters measured below the core surface, r indicates laboratory replicate. (Source: USGS)
    Range of values
    Minimum:0-1
    Maximum:71-72
    Units:centimeters
    Resolution:1
    Water Content (g-water/g-wet)
    The ratio of the mass of water to the mass of wet sediment. (Source: USGS)
    Range of values
    Minimum:0.05
    Maximum:0.88
    Units:Grams of water per grams of wet sediment
    Resolution:0.01
    Porosity (cm^3-voids/cm^3-wet)
    Porosity of the sediment interval (Source: USGS)
    Range of values
    Minimum:0.12
    Maximum:0.95
    Units:Cubic centimeter of void space per cubic centimeter of wet sediment
    Resolution:0.01
    Dry Bulk Density (g/cm^3)
    Dry bulk density of the sediment interval. (Source: USGS)
    Range of values
    Minimum:0.11
    Maximum:1.54
    Units:Grams per cubic centimeter
    Resolution:0.01
    Loss On Ignition (g-OM/g-dry)
    The ratio of the mass of organic matter combusted at 550 Celsius to the pre-combusted mass of dry sediment. (Source: USGS)
    Range of values
    Minimum:0.002
    Maximum:0.495
    Units:Grams of organic matter per grams of dry sediment
    Resolution:0.001
    15BIM09-DA_Marsh_Shear_Vane.xlsx
    Microsoft Excel workbook listing marsh shear vane results for the sites where sediment cores were collected on Dauphin Island, Alabama (USGS FAN 2015-322-FA). (Source: USGS)
    15BIM09-DA_Marsh_Shear_Vane.csv
    Comma-separated values text file listing marsh shear vane results for the sites where sediment cores were collected on Dauphin Island, Alabama (USGS FAN 2015-322-FA). (Source: USGS)
    Site ID
    Site identifier assigned by USGS scientist. (Source: USGS) Character string
    Blade Used (mm)
    The size of the blade used on the end of the shear vane for calculations. (Source: USGS)
    Range of values
    Minimum:20 x 40
    Maximum:50 x 101
    Units:mm, millimeters, shear vane standard sizes
    Resolution:1
    First Full Quadrant Readings (kPa) for NE quadrant
    The amount of pressure required to turn the shear vane one full rotation in the sediment, measured in kilopascals. (Source: USGS)
    Range of values
    Minimum:2.8
    Maximum:34.0
    Units:kilopascals
    Resolution:0.1
    First Full Quadrant Readings (kPa) for SE quadrant
    The amount of pressure required to turn the shear vane one full rotation in the sediment, measured in kilopascals. (Source: USGS)
    Range of values
    Minimum:2.3
    Maximum:82.0
    Units:kilopascals
    Resolution:0.1
    First Full Quadrant Readings (kPa) for SW quadrant
    The amount of pressure required to turn the shear vane one full rotation in the sediment, measured in kilopascals (Source: USGS)
    Range of values
    Minimum:2.3
    Maximum:80.0
    Units:kilopascals
    Resolution:0.1
    First Full Quadrant Readings (kPa) for NW quadrant
    The amount of pressure required to turn the shear vane one full rotation in the sediment, measured in kilopascals (Source: USGS)
    Range of values
    Minimum:2.5
    Maximum:44.0
    Units:kilopascals
    Resolution:0.1
    First Quadrant Average (kPa)
    The average amount of pressure required to turn the shear vane one full rotation in the sediment, measured in kilopascals. (Source: USGS)
    Range of values
    Minimum:2.5
    Maximum:58.0
    Units:kilopascals
    Resolution:0.1
    Second Full Quadrant Readings (kPa) for NE quadrant
    The amount of pressure required to turn the shear vane one full rotation in the sediment, measured in kilopascals. (Source: USGS)
    Range of values
    Minimum:2.9
    Maximum:76.0
    Units:kilopascals
    Resolution:0.1
    Second Full Quadrant Readings (kPa) for SE quadrant
    The amount of pressure required to turn the shear vane one full rotation in the sediment, measured in kilopascals. (Source: USGS)
    Range of values
    Minimum:2.0
    Maximum:80.0
    Units:kilopascals
    Resolution:0.1
    Second Full Quadrant Readings (kPa) for SW quadrant
    The amount of pressure required to turn the shear vane one full rotation in the sediment, measured in kilopascals. (Source: USGS)
    Range of values
    Minimum:2.8
    Maximum:53.0
    Units:kilopascals
    Resolution:0.1
    Second Full Quadrant Readings (kPa) for NW quadrant
    The amount of pressure required to turn the shear vane one full rotation in the sediment, measured in kilopascals. (Source: USGS)
    Range of values
    Minimum:2.0
    Maximum:60.0
    Units:kilopascals
    Resolution:0.1
    Second Quadrant Average (kPa)
    The average amount of pressure required to turn the shear vane one full rotation in the sediment, measured in kilopascals. (Source: USGS)
    Range of values
    Minimum:2.6
    Maximum:66.0
    Units:kilopascals
    Resolution:0.1
    Site Average (kPa)
    The average amount of pressure required to turn the shear vane one full rotation in the sediment, measured in kilopascals. (Source: USGS)
    Range of values
    Minimum:2.6
    Maximum:62.0
    Units:kilopascals
    Resolution:0.1
    15BIM09-DA_M_Alpha_Spectroscopy.xlsx
    Microsoft Excel workbook summarizing the total lead-210 and estimated radium-226 and their associated errors for each depth interval for the sediment cores collected on Dauphin Island, Alabama (USGS FAN 2015-322-FA). The results are provided for each core on its own tab. (Source: USGS)
    15BIM09-DA_M_Alpha_Spectroscopy.csv
    Microsoft Excel workbook summarizing the total lead-210 and estimated radium-226 and their associated errors for each depth interval for the sediment cores collected on Dauphin Island, Alabama (USGS FAN 2015-322-FA). The results are provided for each core on its own tab. (Source: USGS)
    Core ID
    Core identifier assigned by USGS scientist, M indicates the sample is a marsh push core. (Source: USGS) Character string
    Depth (cm)
    Depth interval in centimeters measured below the core surface, r indicates laboratory replicate. (Source: USGS)
    Range of values
    Minimum:0-1
    Maximum:56-57
    Units:centimeters
    Resolution:1
    Total Pb-210 Activity (dpm/g)
    The total activity of lead-210 for each centimeter interval of every core in disintegrations per minute per gram of sediment. (Source: USGS)
    Range of values
    Minimum:0.09
    Maximum:7.93
    Units:Disintegrations per minute per gram
    Resolution:0.01
    Total Pb-210 Error (+/- dpm/g)
    The counting error associated with the total activity of lead-210 for each centimeter interval for every core in disintegrations per minute per gram of sediment. (Source: USGS)
    Range of values
    Minimum:0.00
    Maximum:0.35
    Units:Disintegrations per minute per gram
    Resolution:0.01
    Percent Error (%)
    The percent error associated with lab replicates for the total lead-210 activity. (Source: USGS)
    Range of values
    Minimum:0.08
    Maximum:14.31
    Units:percent
    Resolution:0.01
    15BIM09-DA_M_Grain-Size.xlsx
    Microsoft Excel workbook summarizing grain-size parameters for each centimeter depth interval from sediment cores collected on Dauphin Island, Alabama (USGS FAN 2015-322-FA). The averaged results for each sample, including the number of runs used, the standard deviation of the averaged results, and graphical class-size distributions, are provided for each core on its own tab. (Source: USGS)
    15BIM09-DA_M_Grain-Size.csv
    Comma-separated values text file summarizing grain-size parameters for each centimeter depth interval from sediment cores collected on Dauphin Island, Alabama (USGS FAN 2015-322-FA). The averaged results for each sample, including the number of runs used, the standard deviation of the averaged results, and graphical class-size distributions, are provided. (Source: USGS)
    Entity_and_Attribute_Overview:
    The detailed attribute descriptions for the grain size workbooks are provided in the included data dictionary (Grain-Size_Data_Dictionary.pdf). These metadata are not complete without this file.
    Entity_and_Attribute_Detail_Citation:
    Data dictionary for grain-size data tables, in: Ellis, A.M., Smith, C.G., and Marot, M.E., 2017, The Sedimentological Characteristics and Radiochemistry Data for the Marshes on Dauphin Island, Alabama: U.S. Geological Survey data release, https://doi.org/10.5066/F7VM49J0.

Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
    • Alisha M. Ellis
    • Christopher G. Smith
    • Marci E. Marot
  2. Who also contributed to the data set?
    U.S. Geological Survey, Coastal and Marine Geology Program, St. Petersburg Coastal and Marine Science Center
  3. To whom should users address questions about the data?
    U.S. Geological Survey
    Attn: Alisha M. Ellis
    Geologist
    600 4th Street South
    St. Petersburg, FL
    USA

    727-502-8000 (voice)
    aellis@usgs.gov

Why was the data set created?

Dissemination of processed sediment data from sediment core intervals collected from ten sites on Dauphin Island, Alabama, in August 2015 (USGS FAN 2015-322-FA).

How was the data set created?

  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
    Date: 2015 (process 1 of 9)
    At ten sites on Dauphin Island, marsh push cores were collected with 11.4-cm diameter polycarbonate barrels. Upon retrieval, the cores were visually inspected for an undisturbed surface. A replicate core was collected at site DA31. Core lengths ranged between 24 and 59 cm. The cores were transported upright to the SPCMSC laboratory for sectioning. At select sites, Russian peat augers were collected and occasionally sampled in the field for micropaleontology. The data associated with those peat cores will be made available at another time. Water quality properties were measured with an YSI Professional Plus multi-sensor meter in the standing water at each site where there was standing water. Shear vane measurements were recorded within a couple of meters of each marsh push core site using an AMS field shear vane (https://www.ams-samplers.com/pdfs/ams-Field-Vane-Shear-Tester-Kit.pdf). At each site, four measurements were collected, one in the center of each quadrant of a 1 square meter grid, in order to account for variation in vegetation, sediment, and users. Site coordinates were recorded using a GPS antenna in the NAD83 datum with base station set up. Site location information including latitude, longitude, elevation, environment type, vegetation, and YSI measurements are reported in Excel spreadsheets. Comma-separated values data files containing the tabular data in plain text are included in the download files. Person who carried out this activity:
    U.S. Geological Survey
    Attn: Alisha M. Ellis
    Geologist
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    aellis@usgs.gov
    Data sources produced in this process:
    • 15BIM09-DA_M_Site_Information.zip
    • 15BIM09-DA_M_Water_Parameters.zip
    • 15BIM09-DA_Marsh_Shear_Vane.zip
    Date: 2015 (process 2 of 9)
    Upon return from the field, all marsh push cores were x-rayed vertically onto an iCRco 11 x 14-inch cassette using an Ecotron EPX-F2800 x-ray unit at a distance of 79 cm for a 1:1.015 ratio. The cassette was inserted into and scanned using an iCR3600+ cassette scanner and processed using iCRco QPC XSCAN32 version 2.10. Images were then exported as .tiff files and edited in Adobe Photoshop, using grayscale color inversion and inserting a reference scale bar. Person who carried out this activity:
    U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    Attn: Alisha M. Ellis
    Geologist
    600 4th Street South
    St. Petersburg, FL
    U.S.

    (727) 502-8000 (voice)
    aellis@usgs.gov
    Data sources produced in this process:
    • 15BIM09-DA_M_X-rays.zip
    Date: 2015 (process 3 of 9)
    Following x-raying, all cores were vertically extruded and sectioned into 1-cm intervals at the USGS SPCMSC sediment core laboratory. The outer circumference of each interval was removed to avoid use of sediment that was in contact with the polycarbonate barrel. Each sediment interval was bagged and homogenized. Person who carried out this activity:
    U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    Attn: Alisha M. Ellis
    Geologist
    600 4th Street South
    St. Petersburg, FL
    U.S.

    (727) 502-8000 (voice)
    aellis@usgs.gov
    Date: 2015 (process 4 of 9)
    In the laboratory, marsh core samples were homogenized in the sample bag and the subsample for sediment parameters was extracted and processed for basic sediment characteristics: dry bulk density and porosity. Water content, porosity, and dry bulk density were calculated by determining water mass lost during drying. Known volumes of each wet subsample, usually 30-60 milliliters (mL), were packed into a graduated syringe with 0.5 cubic centimeter (cm^3) resolution. The wet sediment sample was then extruded into a pre-weighed aluminum tray, and the weight was recorded. The wet sediment sample and tray were placed in a drying oven for 48 hours at 60 °C. Water content (?) was determined as the mass of water (lost when dried) relative to the initial wet sediment mass. Porosity (?) was estimated from the equation ? = ? / [?+(1-?)/?s] where ?s is grain density assumed to be 2.5 grams per cubic centimeter (g/cm^3). Salt-mass contributions were removed based on the salinity measured at the time of sample collection. If salinity was not measured in the field, pore water salinity was estimated to be 25. Dry bulk density (g/cm^3) was determined by the ratio of dry sediment to the known volume of sediment packed into the syringe. Water content, porosity and dry bulk density are reported in the Excel spreadsheet. A comma-separated values data file containing the tabular data in plain text is included in the download file. Person who carried out this activity:
    U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    Attn: Alisha M. Ellis
    Geologist
    600 4th Street South
    St. Petersburg, FL
    U.S.

    (727) 502-8000 (voice)
    aellis@usgs.gov
    Data sources produced in this process:
    • 15BIM09-DA_M_Sediment_Physical_Properties.zip
    Date: 2015 (process 5 of 9)
    Organic matter (OM) content was determined with a mass loss technique referred to as loss on ignition (LOI). The dry sediment sample from the previous process was homogenized with a porcelain mortar and pestle. Approximately 2.5 or 5 grams (g) of the dry sediment was placed into a pre-weighed porcelain crucible. The mass of the dried sediment was recorded with a precision of 0.01 g on an analytical balance. The sample was then placed inside a laboratory muffle furnace with stabilizing temperature control. The furnace was heated to 110 °C for a minimum of 6 hours to remove hygroscopic water adsorbed onto the sediment particles. The furnace temperature was then lowered to 60 °C, at which point the sediments could be reweighed safely. The dried sediment was returned to the muffle furnace. The furnace was heated to 550 °C over a period of 30 minutes and kept at 550 °C for 6 hours. The furnace temperature was then lowered to 60 °C, at which point the sediments could be reweighed safely. The mass lost during the 6-hour baking period relative to the 110 °C-dried mass is used as a metric of OM content (modified from Dean, 1974). Approximately 19 percent of the field samples were run in duplicate for LOI to assess precision. Data are reported as a ratio of mass (g) of organic matter to mass (g) of dry sediment (post-110 °C drying). Replicate analyses of loss on ignition are reported for quality assurance in the Excel spreadsheet. A comma-separated values data file containing the tabular data in plain text is included in the download file. Person who carried out this activity:
    U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    Attn: Alisha M. Ellis
    Geologist
    600 4th Street South
    St. Petersburg, FL
    U.S.

    (727) 502-8000 (voice)
    aellis@usgs.gov
    Data sources produced in this process:
    • 15BIM09-DA_M_Sediment_Physical_Properties.zip
    Date: 2015 (process 6 of 9)
    Prior to analyses, sediment samples were digested with 8 mL of 30 percent hydrogen peroxide (H2O2) overnight to remove excess organics. The H2O2 was then evaporated slowly on a hot plate, and the sediment was washed and centrifuged twice with deionized water. To prevent damage to the Coulter LS 13 320, particles greater than 1 millimeter (mm) in diameter were removed with a 1 mm sieve. The samples were washed through the sieve with a five percent solution of sodium hexametaphosphate with filtered municipal water to act as a deflocculant. The sediment slurry was sonicated with a wand sonicator for 30–60 seconds before being introduced into the particle size analyzer. Two subsamples from each sample were processed with a minimum of four runs apiece. The data for each sample was exported as relative volumes for 92 size-classification channels, or bins, which correspond with the size-classification boundaries for American Society for Testing and Materials (ASTM) E11 standard specification for wire cloth and sieves for testing purposes. Person who carried out this activity:
    U.S. Geological Survey
    Attn: Alisha M. Ellis
    Geologist
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    aellis@usgs.gov
    Date: 2015 (process 7 of 9)
    The raw grain-size data were processed with the free software program, GRADISTAT version 8, (Blott and Pye, 2001; kpal.co.uk/gradistat), which calculates the mean, median, sorting, skewness, and kurtosis of each sample geometrically in metric units and logarithmically in phi units (?) (Krumbein, 1934) using the Folk and Ward (1957) method. GRADISTAT also calculates the fraction of sediment from each sample by size category (for example, clay, coarse silt, fine sand) based on Friedman and Saunders (1978), a modified Wentworth (1922) size scale. A macro function in Microsoft Excel, developed by the USGS SPCMSC, was applied to the data to calculate the average and standard deviation for each sample set (8 runs per sample), and highlight runs that varied from the set average by more than ± 1.5 standard deviations. Excessive deviations from the mean are likely the result of equipment error or extraneous organic material in the sample and are not considered representative of the sample. The highlighted runs were removed from the results, and the sample average was recalculated using the remaining runs. The averaged results for all samples, including the number of averaged runs and the standard deviation of the averaged results were summarized in an of Excel workbook with each core on its own tab. A comma-separated values data file containing the tabular data in plain text is included in the download file. Person who carried out this activity:
    U.S. Geological Survey
    Attn: Alisha M. Ellis
    Geologist
    600 4th Street South
    St. Petersburg, FL
    USA

    (727) 502-8000 (voice)
    aellis@usgs.gov
    Data sources produced in this process:
    • 15BIM09-DA_M_Grain-Size.zip
    Date: 2015 (process 8 of 9)
    A subsample of sediment from each centimeter of each core was processed by standard alpha spectrometry procedures using polonium-210 (210Po) (Marot and Smith, 2012; a modification of Robbins and Edgington, 1975) to determine total lead-210 (210Pb) down core. In the laboratory, approximately 3.0 g of dried and homogenized sediment was spiked with 0.5 mL of polonium-209 (209Po), with an activity of 12 disintegrations per minute per milliliter (dpm/mL). The sediment was then leached by the addition and subsequent evaporation to near dryness with a combination of concentrated nitric acid, hydrochloric acid, and 30 percent H2O2. Polonium-210 (210Po) and 209Po were electroplated onto silver planchets and counted twice, in two different chambers, for 24 hours on an ORTEC Alpha Ensemble multi-chamber spectrometer. Count rate efficiency was determined for 209Po and applied to the 210Po counts. The total 210Pb was assumed to be in secular equilibrium with its granddaughter, 210Po in the down-core sediment. The radioisotopic activities reported in the Excel spreadsheet include the counting error for all samples. A comma-separated values data file containing the tabular data in plain text is included in the download file. Person who carried out this activity:
    U.S. Geological Survey St. Petersburg Coastal and Marine Science Center
    Attn: Marci E. Marot
    Geologist
    600 4th Street South
    St. Petersburg, FL
    U.S.

    (727) 502-8000 (voice)
    mmarot@usgs.gov
    Data sources produced in this process:
    • 15BIM09-DA_M_Alpha_Spectroscopy.zip
    Date: 13-Oct-2020 (process 9 of 9)
    Added keywords section with USGS persistent identifier as theme keyword. Person who carried out this activity:
    U.S. Geological Survey
    Attn: VeeAnn A. Cross
    Marine Geologist
    384 Woods Hole Road
    Woods Hole, MA

    508-548-8700 x2251 (voice)
    508-457-2310 (FAX)
    vatnipp@usgs.gov
  3. What similar or related data should the user be aware of?
    Blott, S.J. and Pye, K., 20010928, Gradistat: A grain size distribution and statistics package for the analysis of unconsolidated sediments: Earth Surface Processes and Landforms Volume 26, issue 11.

    Online Links:

    Other_Citation_Details: Pages 1237-1248
    Marot, M.E. and Smith C.G., 2012, Radioisotopic data of sediment collected in Mobile and Bon Secour Bays, Alabama: U.S. Geological Survey Open-File Report 2012–1172.

    Online Links:

    Other_Citation_Details: 15 pages
    Robbins, J. A. and Edgington, D. N., 1975, Determination of recent sedimentation rates in Lake Michigan using Pb-210 and Cs-137: Geochimica et Cosmochimica Acta Volume 39, issue 3.

    Online Links:

    Other_Citation_Details: pages 285–304
    Appleby, P. G. and Oldfield, F., 1978, The calculation of Lead-210 dates assuming a constant rate of supply of unsupported 210Pb to the sediment: Catena Volume 5, issue 1.

    Online Links:

    Other_Citation_Details: Pages 1-8

How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?
    The positional accuracy of the sample locations is determined by the accuracy of the raw position data recorded by the GPS antenna, in the North American Datum of 1983 (NAD83), during data collection. Differential Global Positioning System (DGPS) coordinates were obtained using post-processing software packages (National Geodetic Survey On-Line Positioning User Service, OPUS, and Novatel Waypoint Product Group GrafNav). Replicate analyses of loss on ignition are reported for quality assurance. The grain size data represent the sample averages for a subset of the statistical parameters calculated by GRADISTAT. The number of runs included in the averaged results are reported, and the standard deviation of the averaged results are reported for most parameters. The alpha spectroscopic radioisotope activities reported include the counting error for all samples.
  2. How accurate are the geographic locations?
    All static GPS base station sessions were processed through the On-Line Positioning User Service (OPUS) maintained by the National Geodetic Survey (NGS). The OPUS base-station solutions were entered into a spreadsheet to compute a final, time-weighted positional coordinate (latitude, longitude, and ellipsoid height) for each base station. Base-station positional error was calculated as the absolute value of the final position minus the session position value. The maximum horizontal error of the base station coordinates used for post-processing the sample locations was 0.00005 seconds latitude and 0.00015 seconds longitude.
  3. How accurate are the heights or depths?
    All static GPS base station sessions were processed through OPUS. The OPUS base-station solutions were entered into a spreadsheet to compute a final, time-weighted positional coordinate (latitude, longitude, and ellipsoid height) for each base station. Base-station positional error for each GPS session was calculated as the absolute value of the final position minus the session position value. For this survey, the maximum standard deviation of the base station ellipsoid height was 0.009 m and the maximum vertical error for the base station was +/- 0.016 m. The time-weighted average positions were compared with the NPS network control numbers for each base station; the time-weighted elevations for each base station occupation were within 2 standard deviations of the NPS control elevations. The NPS control coordinates were used for subsequent post processing.
  4. Where are the gaps in the data? What is missing?
    The data release doi:10.5066/F7VM49J0 associated with this metadata includes the geographic site location, water quality parameters, sediment physical properties, grain size statistics, shear vane measurements, and sediment radiochemistry activities for eleven cores collected at ten sties on Dauphin Island, Alabama, in August, 2015.
  5. How consistent are the relationships among the observations, including topology?
    The grain-size sample runs in the GRADISTAT output files for which the mean Folk and Ward (1957) grain size varied from the set average by more than 1.5 standard deviations are highlighted in yellow and were not included in final averaged results. No formal logical accuracy tests were conducted on the remaining datasets.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?
Access_Constraints: None
Use_Constraints:
Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. The U.S. Geological Survey requests that it be acknowledged as the originator of this dataset in any future products or research derived from these data.
  1. Who distributes the data set? (Distributor 1 of 1)
    U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center
    Attn: Alisha M. Ellis
    Geologist
    600 4th Street South
    St. Petersburg, FL
    USA

    727-502-8000 (voice)
    aellis@usgs.gov
  2. What's the catalog number I need to order this data set? Downloadable data
  3. What legal disclaimers am I supposed to read?
    This publication was prepared by an agency of the United States Government. Although these data have been processed successfully on a computer system at the U.S. Geological Survey, no warranty expressed or implied is made regarding the display or utility of the data on any other system, or for general or scientific purposes, nor shall the act of distribution imply any such warranty. The U.S. Geological Survey shall not be held liable for improper or incorrect use of the data described and (or) contained herein. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof.
  4. How can I download or order the data?
  5. What hardware or software do I need in order to use the data set?
    The data tables for USGS FAN 2015-322-FA were created in Microsoft Excel for Mac 2016 version 15.32 and can be opened using Microsoft Excel 2007 or higher; these data may also be viewed using the free Microsoft Excel Viewer (http://office.microsoft.com/). The data tables are also provided as comma-separated values text files (.csv). The .csv data file contains the tabular data in plain text and may be viewed with a standard text editor. Portable Document Format (PDF) files can be viewed using the free software Adobe Acrobat Reader (http://get.adobe.com/reader).

Who wrote the metadata?

Dates:
Last modified: 13-Oct-2020
Metadata author:
U.S. Geological Survey
Attn: Alisha M. Ellis
Geologist
600 4th Street South
St. Petersburg, FL
USA

727-502-8000 (voice)
aellis@usgs.gov
Metadata standard:
Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)
This page is <https://cmgds.marine.usgs.gov/catalog/spcmsc/15BIM09-DA_M_metadata.faq.html>
Generated by mp version 2.9.50 on Tue Sep 21 18:18:29 2021