Location and radiochemical data from sediment cores collected on Deer Island, Mississippi

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Frequently anticipated questions:

What does this data set describe?

Title:
Location and radiochemical data from sediment cores collected on Deer Island, Mississippi
Abstract:
In December 2021, four sediment push cores (core names appended with 'M' for marsh push core) and peat augers (core names appended with 'R' for Russian peat auger) were collected from the marshes of Deer Island, Mississippi during U.S. Geological Survey (USGS) field activity number (FAN) 2021-351-FA. Select intervals from the manual push cores were analyzed for determination of lead-210 activities via alpha spectroscopy for development of accumulation rates using standard model methods. Twenty percent of push core samples were counted in triplicate for determination of a lead-210 activity standard deviation. Select intervals were also run on gamma spectroscopy for lead-210 activity validation and cesium-137 activities. Peat augers were collected for determination of peat thickness and were discarded in the field once described and photographed. Core locations were recorded concurrently using real-time kinematic (RTK) positioning for collection of latitude, longitude and elevation (North American Datum of 1983 (2011) [NAD83_2011] and North American Vertical Datum of 1988 [NAVD88], GEOID12B respectively).
Supplemental_Information:
To ensure that USGS-St. Petersburg Coastal and Marine Science Center (SPCMSC) data management protocols were followed, this survey was assigned the FAN: 2021-351-FA. Additional survey and data details are available on the Coastal and Marine Geoscience Data System (CMGDS) at, https://cmgds.marine.usgs.gov/fan_info.php?fan=2021-351-FA. In December 2021, USGS scientists collected four sediment push cores from three marsh sites on Deer Island, Mississippi located in the northern Gulf of Mexico. Marsh site location data was collected with a Spectra Precision SP80 Global Navigation Satellite System (GNSS) receiving RTK positioning broadcast from the Gulf Coast Geospatial Center’s (GCGC) Real Time Network (RTN). The closest GCGC reference station to Deer Island was Guatier, Mississippi (MSGA). For more information please visit, http://rtn.usm.edu/Map/SensorMap.aspx.
  1. How might this data set be cited?
    Ellis, Alisha M., 20220815, Location and radiochemical data from sediment cores collected on Deer Island, Mississippi:.

    This is part of the following larger work.

    Ellis, Alisha M., Smith, Christopher G., Everhart, Cheyenne S., and DeWitt, Nancy T., 20220815, Radiochemical Data From Sediment Cores Collected on Deer Island, Mississippi: U.S. Geological Survey data release doi:10.5066/P9GGK7VE, U.S. Geological Survey, St. Petersburg, FL.

    Online Links:

  2. What geographic area does the data set cover?
    West_Bounding_Coordinate: -88.84125
    East_Bounding_Coordinate: -88.83838
    North_Bounding_Coordinate: 30.37350
    South_Bounding_Coordinate: 30.37453
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
    Beginning_Date: 15-Dec-2021
    Ending_Date: 16-Dec-2021
    Currentness_Reference:
    Ground condition
  5. What is the general form of this data set?
    Geospatial_Data_Presentation_Form: tabular digital data
  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?
      The horizontal datum used is North American Datum 1983 (corrected to 2011) (NAD83_2011).
      The ellipsoid used is Geodetic Reference System 80 (GRS80).
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257222101.
  7. How does the data set describe geographic features?
    DeerIsland_SiteInfo.xlsx
    Microsoft Excel workbook defining the field sampling dates, site locations, elevations, core lengths and compaction for the push and peat auger cores collected from Deer Island, Mississippi (USGS FAN 2021-351-FA). A value of a double dash indicates that there is no data for that core or sample. (Source: USGS)
    DeerIsland_SiteInfo.csv
    Comma-separated values text file defining the field sampling dates, site locations, elevations, core lengths and compaction for the push and peat auger cores collected from Deer Island, Mississippi (USGS FAN 2021-351-FA). A value of a double dash indicates that there is no data for that core. (Source: USGS)
    SiteID
    Site identifier assigned by USGS scientist consisting of 'DR' to indicate Deer Island and a three-digit number. (Source: USGS) Character string
    SampleID
    Sample identifier assigned by USGS scientist consisting of 'DR' to indicate Deer Island and a three-digit number appended with either 'M', indicating a marsh push core, or 'R', indicating a Russian peat auger, and an additional (A) or (B) to indicate a field replicate. (Source: USGS) Character string
    Collection_Date
    Date identifier, in MM/DD/YYYY format (Source: USGS)
    Range of values
    Minimum:12/15/2021
    Maximum:12/16/2021
    Easting_NAD83_2011
    Easting of station location, in meters (North American Datum of 1983, corrected to 2011). (Source: USGS)
    Range of values
    Minimum:323071.40540
    Maximum:324067.75361
    Units:Meters
    Resolution:0.00001
    Northing_NAD83_2011
    Northing of station location, in meters (North American Datum of 1983, corrected to 2011). (Source: USGS)
    Range of values
    Minimum:3361606.19076
    Maximum:3361725.39945
    Units:Meters
    Resolution:0.00001
    Latitude_NAD83_2011
    Latitude of station location, in decimal degrees (North American Datum of 1983, corrected to 2011). (Source: USGS)
    Range of values
    Minimum:30.37119
    Maximum:30.37453
    Units:Decimal degrees
    Resolution:0.00001
    Longitude_NAD83_2011
    Longitude of site location, in decimal degrees (North American Datum of 1983, corrected to 2011). (Source: USGS)
    Range of values
    Minimum:-88.84125
    Maximum:-88.83084
    Units:Decimal degrees
    Resolution:0.00001
    Elevation_NAVD88_GEOID12B
    Elevation of site location, in meters (North American Vertical Datum of 1988, GEOID 12B). (Source: USGS)
    Range of values
    Minimum:0.36335
    Maximum:0.42205
    Units:meters
    Resolution:0.00001
    Field_Estimated_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:19.0
    Maximum:41.0
    Units:centimeters
    Resolution:1.0
    Coring_Compaction_cm
    The approximate amount of compaction, or core shortening, withstood by the push core, in centimeters, as recorded in the field. (Source: USGS)
    Range of values
    Minimum:0.0
    Maximum:19.0
    Units:centimeters
    Resolution:1.0
    Peat_Auger_Length_cm
    The total length of the Russian peat auger collected at each site in centimeters, as recorded in the field. (Source: USGS)
    Range of values
    Minimum:44.0
    Maximum:150.0
    Units:centimeters
    Resolution:0.5
    DeerIsland_GammaSpectroscopy.xlsx
    Microsoft Excel workbook summarizing the total beryllium-7, cesium-137, lead-210, radium-226, thorium-234, and potassium-40 activities and the associated errors for select depth intervals for two sediment cores collected from Deer Island, Mississippi (USGS FAN 2021-351-FA). Values of 'ND' indicate not detected. (Source: USGS)
    DeerIsland_GammaSpectroscopy.csv
    Comma-separated values text file summarizing the total beryllium-7, cesium-137, lead-210, radium-226, thorium-234, and potassium-40 activities and the associated errors for select depth intervals for two sediment cores collected from Deer Island, Mississippi (USGS FAN 2021-351-FA). Values of 'ND' indicate not detected. (Source: USGS)
    CoreID
    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. (Source: USGS)
    Range of values
    Minimum:24-26
    Maximum:38-40
    Units:centimeters
    Resolution:2.0
    Cs-137_Activity_dpm/g
    The total activity of cesium-137 for each interval in disintegrations per minute per gram of sediment. (Source: USGS)
    Range of values
    Minimum:0.06
    Maximum:0.06
    Units:Disintegrations per minute per gram
    Resolution:0.01
    Cs-137_Activity_Error_+/-dpm/g
    The counting error associated with the total activity of cesium-137 for each interval in disintegrations per minute per gram of sediment. (Source: USGS)
    Range of values
    Minimum:0.03
    Maximum:0.03
    Units:Disintegrations per minute per gram
    Resolution:0.01
    Pb-210_Activity_dpm/g
    The total activity of lead-210 for each interval in disintegrations per minute per gram of sediment. (Source: USGS)
    Range of values
    Minimum:0.79
    Maximum:1.22
    Units:Disintegrations per minute per gram
    Resolution:0.01
    Pb-210_Activity_Error_+/-dpm/g
    The counting error associated with the total activity of lead-210 for each interval in disintegrations per minute per gram of sediment. (Source: USGS)
    Range of values
    Minimum:0.10
    Maximum:0.19
    Units:Disintegrations per minute per gram
    Resolution:0.01
    Ra-226_Activity_dpm/g
    The total activity of radium-226 for each interval in disintegrations per minute per gram of sediment. (Source: USGS)
    Range of values
    Minimum:0.78
    Maximum:1.01
    Units:Disintegrations per minute per gram
    Resolution:0.01
    Ra-226_Activity_Error_+/-dpm/g
    The counting error associated with the total activity of radium-226 for each interval in disintegrations per minute per gram of sediment. (Source: USGS)
    Range of values
    Minimum:0.04
    Maximum:0.07
    Units:Disintegrations per minute per gram
    Resolution:0.01
    Th-234_Activity_dpm/g
    The total activity of thorium-234 for each interval in disintegrations per minute per gram of sediment. (Source: USGS)
    Range of values
    Minimum:0.88
    Maximum:1.58
    Units:Disintegrations per minute per gram
    Resolution:0.01
    Th-234_Activity_Error_+/-dpm/g
    The counting error associated with the total activity of thorium-234 for each interval in disintegrations per minute per gram of sediment. (Source: USGS)
    Range of values
    Minimum:0.13
    Maximum:0.22
    Units:Disintegrations per minute per gram
    Resolution:0.01
    K-40_Activity_dpm/g
    The total activity of potassium-40 for each interval in disintegrations per minute per gram of sediment. (Source: USGS)
    Range of values
    Minimum:3.83
    Maximum:6.71
    Units:Disintegrations per minute per gram
    Resolution:0.01
    K-40_Activity_Error_+/-dpm/g
    The counting error associated with the total activity of potassium-40 for each interval in disintegrations per minute per gram of sediment. (Source: USGS)
    Range of values
    Minimum:0.45
    Maximum:0.78
    Units:Disintegrations per minute per gram
    Resolution:0.01
    DeerIsland_AlphaSpectroscopy.xlsx
    Microsoft Excel workbook summarizing the total lead-210 activities and the associated errors for each depth interval for the sediment cores collected from Deer Island, Mississippi (USGS FAN 2021-351-FA). The results are provided for each core on its own tab. 'N/A' indicates calculation is not applicable for that sample. (Source: USGS)
    DeerIsland_AlphaSpectroscopy.csv
    Comma-separated values text file summarizing the total lead-210 activities and the associated errors for each depth interval for the sediment cores collected from Deer Island, Mississippi (USGS FAN 2021-351-FA). 'N/A' indicates calculation is not applicable for that sample. (Source: USGS)
    CoreID
    Core identifier assigned by USGS scientist; 'DR' indicates Deer Island, followed by a three-digit identification number and appended with 'M' for marsh push core. Push cores from site DR012 are also appended with (A) and (B) indicates field core replicates. (Source: USGS) Character string
    Depth_cm
    Depth interval in centimeters for the surface sample. (Source: USGS)
    Range of values
    Minimum:0-2
    Maximum:38-40
    Units:centimeters
    Resolution:2.0
    Total_Pb-210_Activity_dpm/g
    The total activity of Pb-210 for each interval in disintegrations per minute per gram of sediment. (Source: USGS)
    Range of values
    Minimum:0.153
    Maximum:5.446
    Units:Disintegrations per minute per gram
    Resolution:0.001
    Total_Pb-210_Activity_Error_+/-dpm/g
    The counting error associated with the total activity of lead-210 for each interval in disintegrations per minute per gram of sediment. (Source: USGS)
    Range of values
    Minimum:0.007
    Maximum:0.133
    Units:Disintegrations per minute per gram
    Resolution:0.001
    Percent_Difference_%
    The percent difference of lead-210 for each interval counted in replicate. (Source: USGS)
    Range of values
    Minimum:1.382
    Maximum:5.776
    Units:Disintegrations per minute per gram
    Resolution:0.001
    Standard_Deviation_dpm/g
    The standard deviation of lead-210 for each two-centimeter interval counted in triplicate in disintegrations per minute per gram of sediment. (Source: USGS)
    Range of values
    Minimum:0.003
    Maximum:0.105
    Units:Disintegrations per minute per gram
    Resolution:0.01

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
  2. Who also contributed to the data set?
    U.S. Geological Survey, Coastal and Marine Geology Program, St. Petersburg Coastal and Marine Science Center and U.S. Army Corps of Engineers
  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 core intervals collected from Deer Island, Mississippi (FAN 2021-351-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: 2021 (process 1 of 3)
    At the three marsh sites, four marsh push cores were collected with 10.16-centimeter (cm) diameter polycarbonate barrels. Upon retrieval, the cores were visually inspected for disturbances (for example, slumping, washout, scouring, cracking, bubbling, and/or discontinuities) to ensure the core was intact and representative of the site. If the core appeared disturbed, it was discarded, and a new core was collected and inspected. These methods are similar to those described in Osbourne and DeLaune (2013), with the exception of not adding water for extraction when sediments were already saturated and calculation of compaction due to coring (Morton and White, 1997). Core lengths ranged between 19 and 41 cm. The cores were transported upright to avoid slumping and preserve the natural sediment orientation. Cores were transferred to a contact at the U.S. Army Corps of Engineers (USACE) for sectioning and drying. At each marsh site, Russian peat augers were collected in agreement with the methods described in Osbourne and DeLaune (2013) and manufacturer recommendations. Visual characteristics of the peat augers were described (for example, general color; visual organic matter texture and type such as roots, bivalves, and level of decomposition; and sediment texture such as sandy silt or clayey silt) and thickness of the upper organic-bearing unit (peat) was recorded in field forms, in centimeters. Once described and photographed horizontally with a scale bar and label, peat augers were discarded in the field. The field forms associated with those peat augers include handwritten notes visible on the field forms for each site. Sample identifiers consist of a site-specific identifier (for example, DR021), and appended with an alphabetic identifier to differentiate the sediment collection method (M for marsh push core, R for Russian peat auger). Marsh site coordinates were recorded using a handheld GPS in addition to an the SP80 GNSS receiver’s RTK position (NAD83_2011, NAVD88) in case of RTK failure. Site location information includes site ID, core ID, date collected, easting, northing, latitude, longitude, elevation, core lengths and coring compaction which are reported in an Excel spreadsheet (.xlsx). Comma-separated values (.csv) 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:
    • DeerIsland_SiteInfo.xlsx, DeerIsland_SiteInfo.csv
    Date: 2022 (process 2 of 3)
    Dried, ground sediment intervals from the four push cores were received from the USACE and analyzed for the detection of radionuclides by standard alpha and gamma-ray spectrometry in the USGS SPCMSC radioisotope labs. Total lead-210 (Pb-210, half-life = 22.3 years) activity was measured by alpha spectrometry on two-centimeter intervals of four marsh push cores for the entire length of the cores. Polonium-210 (Po-210, half-life = 138 days) is assumed to be in secular equilibrium with its parent Pb-210, allowing for the determination of the total Pb-210 activity in environmental sediments by directly measuring the activity of Po-210 through alpha particle decay. The USGS SPCMSC radioisotope laboratory uses a method that was originally developed by Martin and Rice (1981) to chemically separate Po-210 from sediments. This method utilizes polonium’s affinity to autoplate to silver planchets in order to isolate Po-210 for alpha counting (Flynn, 1968). To separate the Po-210, 5.00 grams (g) of dried, ground sediment sample was leached with 10 milliliters (mL) 16 normality (N) nitric acid (HNO3) and a polonium-209 (Po-209) tracer was added. The solution digested overnight and was then dried on a hotplate. The dried solution was washed with 5 mL of 8 N hydrochloric acid (HCl), followed by three washings with 30% hydrogen peroxide (H2O2) to break down organics. After two additional washings with 5 mL of 8 N hydrochloric acid, 5 mL of 8 N hydrochloric acid was added. Once the sample dissolved completely, the solution was brought to 50 mL by adding deionized water. Three reagents were added prior to the deposition of Po-210 onto the silver planchets: 20% hydroxylamine hydrochloride and 25% sodium citrate were added to reduce the inference of oxidants, such as iron+3 (Fe+3) and chromium+6 (Cr+6) and a 2.2% weight by volume solution of bismuth nitrate was added to help prevent the deposition of bismuth-212 (Martin and Rice, 1981). A calibrated handheld pH meter was used to monitor the pH of the solution. Ammonium hydroxide was added dropwise while mixing to achieve a pH of 1.85 to 1.95. The Po-210 was autoplated onto the 1.9-centimeter diameter sterling silver planchets as the solution was heated and stirred on a hotplate for 2 hours. All planchets had one side covered with tape to ensure Po-210 plating only occurred on one side. The planchets were removed from solution, rinsed with deionized water, and dried. The planchets were counted in low-level alpha spectrometers coupled to a pulse-height analyzer for 24 hours. Samples with low Po-210 activity were counted for 48 hours. The total Pb-210 activity and counting error are reported in the Excel spreadsheet. A .csv 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:
    • DeerIsland_AlphaSpectrometry.xlsx, DeerIsland_AlphaSpectrometry.csv
    Date: 2022 (process 3 of 3)
    Select two-centimeter intervals were analyzed from each core by gamma-ray spectrometry. The sediments were sealed in airtight polypropylene containers with plumbers' tape around the threads for the planar detectors, or polystyrene test tubes for the well detector. Sediments placed in the test tubes were sealed with a layer of epoxy. The sealed samples were stored for a minimum of 3 weeks prior to analysis to allow radium-226 (Ra-226) to come into secular equilibrium with its progeny isotopes, lead-214 (Pb-214) and bismuth-214 (Bi-214). The sealed samples were then counted for 24-95 hours on a 16 x 40-millimeter well, or 50-millimeter diameter planar-style, low energy, high-purity germanium, gamma-ray spectrometer. The suite of naturally occurring and anthropogenic radioisotopes measured along with their corresponding photopeak energies in kiloelectron volts (keV) are lead-210 (Pb-210, 46.5 keV), thorium-234 (Th-234, 63.3 keV), Pb-214 (295.7 and 352.5 keV; proxies for Ra-226), beryllium-7 (477.6 keV), Bi-214 (609.3 keV; proxy for Ra-226), cesium-137 (Cs-137, 661.6 keV), and potassium-40 (K-40, 1640.8 keV). Sample count rates were corrected for detector efficiency determined with International Atomic Energy Agency RGU-1 reference material, standard photopeak intensity, and self-absorption using a uranium-238 (U-238) sealed source (planar detectors only, Cutshall and others, 1983). All activities, with the exception of short-lived Pb-214 and Bi-214, were decay-corrected to the date of field collection. The radioisotopic activities reported in the Excel spreadsheet include the counting error for all samples. A .csv data file containing the tabular data in plain text is also 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:
    • DeerIsland_GammaSpectrometry.xlsx, DeerIsland_GammaSpectrometry.csv
  3. What similar or related data should the user be aware of?
    Osbourne, T.Z., and DeLaune R.D., 20131018, Soil and sediment sampling of inundated environments: Methods in Biogeochemistry of Wetlands Volume 10.

    Online Links:

    Other_Citation_Details: Pages 21-41
    Cutshall, N.H., Larsen, I.L., and Olsen, C.R., 19830215, Direct analysis of Pb-210 in sediment samples: a self-absorption corrections: Nuclear Instruments and Methods in Physics Research Volume 206, Issues 1-2.

    Online Links:

    Other_Citation_Details: Pages 309-312
    Martin, E.A., and Rice, C.A., 1981, Sampling and analyzing sediment cores for 210Pb geochronology: U.S. Geological Survey Open-File Report 81-983.

    Online Links:

    Flynn, W.W., 1968, The determination of low levels of polonium-210 in environmental materials: Analytica Chimica Acta Volume 43.

    Online Links:

    Other_Citation_Details: Pages 221-227
    Morton, R.A., and White, W.A., 1997, Characteristics of and corrections for core shortening in unconsolidated sediments: Journal of Coastal Research Volume 13, No. 3.

    Online Links:

    Other_Citation_Details: Pages 761-769

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 SP80 GNSS antenna, in NAD83_2011 and NAVD88 National Geodetic Survey (NGS) GEOID12B datum, during data collection. RTK positioning was obtained by receiving corrections broadcast by the GCGC Guatier, Mississippi (MSGSA) Continuously Operating Reference Station (CORS). The alpha spectroscopic radioisotope activities reported include the counting error for all samples. The critical level for gamma spectroscopy is reported for each core set.
  2. How accurate are the geographic locations?
    Position information (x, y, z; latitude, longitude, elevation) was collect the at each core site with RTK Global Positioning Systems (GPS) using the Spectra Precision SP80 Global Navigation Satellite Systems (GNSS) receiver and an Ashtech Handheld MobileMapper10 (MM10) running Carlson SurvCE version 6 software. The SP80 and MM10 were configured to receive the positional corrections from the GCGC RTN. The RTN network broadcasts horizontal positions in NAD83_2011. When using an RTN network, the SP80 specification sheet reports horizontal accuracy of 8-millimeter (mm) + 0.5 parts per million (ppm). RTK data was collected for at least 15 minutes at each site, referencing between 10-14 satellites. All position status reported as fixed. Position Dilution of Precision (PDOP) ranged from 0.991 to 1.476, and Horizontal Dilution of Precision (HDOP) ranged from 0.53 to 0.70.
  3. How accurate are the heights or depths?
    Position information (x, y, z; latitude, longitude, elevation) was collect the at each core site with RTK GPS using the Spectra Precision SP80 GNSS receiver and an Ashtech Handheld MobileMapper10 (MM10) running Carlson SurvCE version 6 software. The SP80 and MM10 were configured to receive the positional corrections from the GCGC RTN. The RTN network broadcasts vertical positions in NAVD88. The SurveCE6 software job specifications were programmed to use the GEOID 12B model and account for the stadia rod height (1.75 meters [m]) at each core site. When using an RTN network, the SP80 specification sheet reports vertical accuracy of 15-mm + 0.5 ppm. RTK data was collected for at least 15 minutes at each site, referencing between 10-14 satellites. All position status reported as fixed. PDOP ranged from 0.991 to 1.476, and Vertical Dilution of Precision (VDOP) ranged from 0.83 to 1.30.
  4. Where are the gaps in the data? What is missing?
    This data release doi:10.5066/P9GGK7VE contains all sediment data associated with USGS FAN 2021-351-FA and includes the geographic site location and sediment radiochemistry activities for cores collected from marsh environments on Deer Island, Mississippi marsh in December 2021.
  5. How consistent are the relationships among the observations, including topology?
    Select intervals for alpha spectrometry activities were counted in triplicate for development of a standard deviation for the individual sample. Select intervals were analyzed via alpha and gamma spectroscopy for direct comparison of activity values utilizing two independent methods. A secondary review was performed on all laboratory data by qualified personnel not involved in the calculation or compilation of results to verify that the data are accurate and complete. No other formal logical accuracy tests were conducted on the 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? DeerIsland_SiteInfo.csv, DeerIsland_SiteInfo.xlsx, DeerIsland_AlphaSpectroscopy.csv, DeerIsland_AlphaSpectroscopy.xlsx, DeerIsland_GammaSpectroscopy.csv, DeerIsland_GammaSpectroscopy.xlsx
  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 2021-351-FA were created in Microsoft Excel 365 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 files contain the tabular data in plain text and may be viewed with a standard text editor.

Who wrote the metadata?

Dates:
Last modified: 02-Dec-2022
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/DeerIsland_metadata.faq.html>
Generated by mp version 2.9.51 on Fri Dec 2 09:59:30 2022