Peat Thickness Measurements from Grand Bay, Mississippi and Alabama

Frequently anticipated questions:

• What does this data set describe?
  1. How might this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
• Who produced the data set?
  1. Who are the originators of the data set?
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
• Why was the data set created?
• How was the data set created?
  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
  3. What similar or related data should the user be aware of?
• How reliable are the data; what problems remain in the data set?
  1. How well have the observations been checked?
  2. How accurate are the geographic locations?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
  5. How consistent are the relationships among the data, including topology?
• How can someone get a copy of the data set?
  1. Are there legal restrictions on access or use of the data?
  2. Who distributes the data?
  3. What's the catalog number I need to order this data set?
  4. What legal disclaimers am I supposed to read?
  5. How can I download or order the data?
• Who wrote the metadata?

What does this data set describe?

1. How might this data set be cited?
   Smith, Christopher G., and Ellis, Alisha M., 20241220, Peat Thickness Measurements from Grand Bay, Mississippi and Alabama:.

   This is part of the following larger work.
   Smith, Christopher G., and Ellis, Alisha M., 20241220, Peat Thickness Measurements From Grand Bay, Mississippi and Alabama: U.S. Geological Survey data release doi:10.5066/P13BDDHQ, U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL.

   Online Links:

   • https://doi.org/10.5066/P13BDDHQ

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -88.43337962
   East_Bounding_Coordinate: -88.31070549
   North_Bounding_Coordinate: 30.41425474
   South_Bounding_Coordinate: 30.34965288
   

3. What does it look like?
4. Does the data set describe conditions during a particular time period?

   Beginning_Date: 14-Apr-2013

   Ending_Date: 18-Jul-2018

   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. It contains the following vector data types (SDTS terminology):
      • Point (57)
   2. What coordinate system is used to represent geographic features?
      

      Grid_Coordinate_System_Name: Universal Transverse Mercator
      Universal_Transverse_Mercator:

      UTM_Zone_Number: 16
      Transverse_Mercator:

      Scale_Factor_at_Central_Meridian: 0.9996
      Longitude_of_Central_Meridian: -87.0
      Latitude_of_Projection_Origin: 0.0
      False_Easting: 500000.0
      False_Northing: 0.0
      

      Planar coordinates are encoded using coordinate pair
      Abscissae (x-coordinates) are specified to the nearest 0.6096
      Ordinates (y-coordinates) are specified to the nearest 0.6096
      Planar coordinates are specified in Meter
      The horizontal datum used is North American Datum 1983.
      The ellipsoid used is Geodetic Reference System 80.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257222101.
      

      Vertical_Coordinate_System_Definition:

      Altitude_System_Definition:

      Altitude_Datum_Name: North American Vertical Datum 1988
      Altitude_Resolution: 0.0001
      Altitude_Distance_Units: meters
      Altitude_Encoding_Method: Attribute values
      

7. How does the data set describe geographic features?

   PeatThickness_SiteInfo.csv

   Comma-separated values text file (.csv) including the site locations, Universal Transverse Mercator (UTM) x and y planar coordinates in meters, orthometric elevations/heights, observed peat thickness, the distance from the core site to both the upland boundary and shoreline, and the angle along the marsh transects, width along the marsh transect, as well as distances (only) for water's edge, Bayou Heron, Middle Bayou, and Bayou Cumbest. (Source: USGS)

   USGS_Alt_FAN

   Alternate field activity number assigned by the USGS to the sample collection/survey. (Source: USGS) Alternate FAN numbers were assigned by the USGS as YYLLLXX, where YY is the 2-digit year, LLL equals either CCT (coastal change and transport) or BIM (barrier island migration), and XX is the trip number.

   SiteID

   Site identifier assigned by USGS scientists consisting of GB to indicate Grand Bay and a three-digit number, representing the study site. (Source: USGS) Alphanumeric site identifier assigned as the following: the site location name abbreviation ('GB' for Grand Bay) followed by a three-digit number.

   UTMx_NAD83_m

   Universal Transverse Mercator (UTM, zone 16) horizontal station location, on the x coordinate plane, in meters (North American Datum of 1983). (Source: USGS)

   Range of values
   Minimum:	362322.7915
   Maximum:	374027.223
   Units:	meters

   UTMy_NAD83_m

   Universal Transverse Mercator (UTM, zone 16) vertical station location, on the y coordinate plane, in meters (North American Datum of 1983). (Source: USGS)

   Range of values
   Minimum:	3358400.473
   Maximum:	3365419.583
   Units:	meters

   Orth_Height_m

   The orthometric height, or land elevation, in meters, of each site relative to the North American Vertical Datum of 1988 (NAVD88) and GEOID12A. (Source: USGS)

   Range of values
   Minimum:	-0.026
   Maximum:	0.750
   Units:	meters

   Obs_PeatThickness_m

   The observed or measured thickness of the peat layer in the peat auger cores collected in the field, recorded in meters. (Source: USGS)

   Range of values
   Minimum:	0.04
   Maximum:	1.69
   Units:	meters

   BasePeat_m

   The estimated elevation of the basal marsh contact, in meters, at each site relative to NAVD88 GEOID12A. (Source: USGS)

   Range of values
   Minimum:	-1.114
   Maximum:	0.681
   Units:	meters (m)

   Bearing_of_MarshTransect_degrees

   The bearing of the line created from the shoreline, through the core location, extending to the upland boundary, determined using geoprocessing tools from the Data Management and Analysis Toolboxes in ArcGIS Pro. (Source: USGS)

   Range of values
   Minimum:	38.109197
   Maximum:	310.419187
   Units:	degrees

   Distance_Upland_m

   The distance from the core location to the upland boundary as determined using geoprocessing tools from the Data Management and Analysis Toolboxes in ArcGIS Pro with 2015 shorelines, in meters. (Source: USGS)

   Range of values
   Minimum:	2.249366435
   Maximum:	3452.165406
   Units:	meters (m)

   Distance_Shore_m

   The distance from the core location to the shoreline as determined using geoprocessing tools from the Data Management and Analysis Toolboxes in ArcGIS Pro with 2015 shorelines, in meters. (Source: USGS)

   Range of values
   Minimum:	0.777162307
   Maximum:	2835.353174
   Units:	meters (m)

   Marsh_width_m

   The distance along the line for each site from the upland boundary to the core location, out to the shoreline, as determined using geoprocessing tools from the Data Management and Analysis Toolboxes in ArcGIS Pro with 2015 shorelines, in meters. Also defined as: Dist_Shoreline_2015_m + Dist_Upland_2015_m. (Source: USGS)

   Range of values
   Minimum:	156.3708545
   Maximum:	4027.886561
   Units:	meters (m)

   Distance_watersedge_m

   The distance from the core location to the closest shoreline feature. Values determined using geoprocessing tools from the Data Management and Analysis Toolboxes in ArcGIS Pro with 2015 shorelines, in meters. (Source: USGS)

   Range of values
   Minimum:	1.186665625
   Maximum:	411.1475323
   Units:	meters (m)

   Distance_bayouheron_m

   The distance from the core location to the closest shoreline feature. Values determined using geoprocessing tools from the Data Management and Analysis Toolboxes in ArcGIS Pro with modified 2015 shoreline of Bayou Heron, in meters. (Source: USGS)

   Range of values
   Minimum:	104.8223491
   Maximum:	8081.254984
   Units:	meters (m)

   Distance_middlebayou_m

   The distance from the core location to the closest shoreline feature . Values determined using geoprocessing tools from the Data Management and Analysis Toolboxes in ArcGIS Pro with modified 2015 shoreline of Middle Bayou, in meters. (Source: USGS)

   Range of values
   Minimum:	58.33454547
   Maximum:	9362.769929
   Units:	meters (m)

   Distance_bayoucumbest_m

   The distance from the core location to the closest shoreline feature. Values determined using geoprocessing tools from the Data Management and Analysis Toolboxes in ArcGIS Pro with modified 2015 shoreline of Bayou Cumbest, in meters. (Source: USGS)

   Range of values
   Minimum:	103.9393615
   Maximum:	9457.296124
   Units:	meters (m)

   Entity_and_Attribute_Overview:

   This data product includes field collected and ArcGIS Pro derived data associated with six USGS FANs. Data includes site locations, Universal Transverse Mercator (UTM) x and y planar coordinates in meters, orthometric elevations/heights, observed peat thickness, the distance from the core site to both the upland boundary and shoreline, and the angle along the marsh transects, width along the marsh transect, as well as distances (only) for water's edge, Bayou Heron, Middle Bayou, and Bayou Cumbest.

   Entity_and_Attribute_Detail_Citation:

   The entity and attribute information were generated by the individual and/or agency identified as the originator of the dataset. Please review the rest of the metadata record for additional details and information.

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • Christopher G. Smith
   • Alisha M. Ellis
2. Who also contributed to the data set?
   Acknowledgment of the U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center as a data source would be appreciated in products developed from these data, and such acknowledgment as is standard for citation and legal practices. Sharing of new data layers developed directly from these data would also be appreciated by the U.S. Geological Survey staff. Users should be aware that comparisons with other datasets for the same area from other time periods may be inaccurate due to inconsistencies in data collection methods. These data are not legal documents and are not to be used as such.
3. To whom should users address questions about the data?
   U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center

   Attn: Christopher G. Smith

   Research Geologist

   600 4th Street South

   St. Petersburg, FL
   

   US

   (727) 502-8000 (voice)

   cgsmith@usgs.gov

Why was the data set created?

How was the data set created?

1. From what previous works were the data drawn?

   Terrano and others (2018) (source 1 of 1)

   Terrano, J.F., Smith, K.E.L., Pitchford, J., McIlwain, J., and Archer, M., 20180926, Shoreline change analysis for the Grand Bay National Estuarine Research Reserve, Mississippi Alabama 1848 to 2017: - St. Petersburg Coastal and Marine Science Center, St. Petersburg, FL.

   Online Links:

   • https://doi.org/10.5066/P9JMA8WK

   Type_of_Source_Media: shapefile
   Source_Contribution:

   Shorelines from 2015 used to determine the distance from the core location to the shoreline and upland boundary in ArcGIS Pro.

2. How were the data generated, processed, and modified?

   Date: 2018 (process 1 of 3)

   During the field missions at each site, 50-cm vertical sections of sediment were extracted from the marsh subsurface using a Russian Peat Auger; each section was successively deeper than the previous until the auger met refusal at depth. Each vertical core consisted of half-cylinder sections of marsh subsurface sediment. Each core segment was scaled with a measuring tape, described in the field for basic/visual stratigraphic and sedimentologic characteristics, and photographed in the field. If the peat unit was fully penetrated, the overall thickness of the overlying organic-rich unit was documented and recorded on site. Upon return from the field, photographs of the cores were examined to verify the peat thickness field observation. If the field description and photographed organic-rich unit for each were in agreement, the marsh thickness was included. A total of 57 cores were collected within the Grand Bay study area and are included in this release. Person who carried out this activity:
   

   U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center

   Attn: Christopher G. Smith

   Research Geologist

   600 4th Street South

   St. Petersburg, FL
   

   U.S.

   (727) 502-8000 (voice)

   cgsmith@usgs.gov

   Date: 2018 (process 2 of 3)

   Positional data (location and elevation) and the associated methods used to derive the horizontal and vertical positions have been published and described in Marot and others (2018), Marot and others (2019), Ellis and others (2022), and Smith and others (2020). All USGS collected location data utilized a global positioning system (GPS) base station erected on National Geodetic Survey (NGS) permanent identifier (PID) DO5987 (B166) located at the boat ramp at the end of Bayou Heron Road in Grand Bay, MS. A differential GPS (DGPS) rover receiver, with a known measured antenna height, was used in the field to collect positional data with occupation times of 30 minutes. Base station coordinates were established using the NGS On-Line Position User Service (OPUS, https://geodesy.noaa.gov/OPUS/). Location data was processed with NovAtel's GrafNav. Location data collected by the Grand Bay National Estuarine Research Reserve utilized a Trimble R10 GNSS and TSC3 data collector. Vertical and horizontal errors associated with each dataset can be found in the metadata of its associated data release. Person who carried out this activity:
   

   U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center

   Attn: Christopher G. Smith

   Research Geologist

   600 4th Street South

   St. Petersburg, FL
   

   U.S.

   (727) 502-8000 (voice)

   cgsmith@usgs.gov

   Date: 2020 (process 3 of 3)

   All field-collected location data was brought into ArcGIS Pro (v. 3.1) in its native format (varied by FAN and available in the associated metadata files) and converted/projected to a Universal Transverse Mercator (UTM) planar coordinate system (zone 16) to allow for all measurements to be cartesian lengths. Geospatial variables were extracted from the marsh core locations relative to the arcuate-shaped feature of the estuarine-marsh and upland-marsh boundaries in the study area which reflect the antecedent morphology. Using ArcGIS Pro 3.1 (hereafter AGP) with a UTM projected coordinate system, the upland and river boundary from the 2015 shoreline data set used by Terrano and others (2018) were digitized. Additional smoothed, offset boundaries (buffered) were created from the detailed boundaries to reflect the more general arcuate nature of the Middle and Grand Bays using the Buffer tool in AGP and a 50-meter offset. The shoreline boundary line was converted to points with ten-meter spacing using Terrano and others (2018) transects using the AGP 'Intersect' geoprocessing tool. The 'Near Table' geoprocessing tool was used with Geodesic setting and with the core dataset as the input layer and the shoreline point shapefile as the near layer. Core coordinates (original as measured with GPS), Core Site ID (as a static input), near angle, distance, and targeted shoreline point coordinates were produced as part of the tool s results. A temporary point file shapefile (hereafter the target-shoreline point) was created from the Near Table results (approximately 500 points). The near angle computed as core-to-shoreline was transformed to bearing to reflect shoreline-to-core and added to the target-shoreline point file. The Bearing Distance to Line geoprocessing tool was used to construct a new line shapefile with the target-shoreline point as the origin, transformed bearing, and a set distance of 5000 meters. The point intersection (coordinates) between the generated lines and the upland boundary was added to the target-shoreline point file. The lines were then extended to intersect the buffered boundaries using the Extend Line tool in AGP and the distance of the line updated (i.e., distance between the modified boundaries). This distance was added to target-shoreline-point file. The target-shoreline-point file was reduced to one record per core site using the minimum distance between the modified boundaries per core site. Distance to shoreline, distance to upland, and width were computed from the coordinates of each core and the respective near shoreline point and near upland point. Distance of each new line segment (distance from to the upland boundary, distance to the shoreline, and width) along with bearing of near transect was written to the original core point shapefile s attribute table. The closest distance between a core site and nearby major tidal creeks (Bayou Heron, Middle Bayou, and Bayou Cumbest) and the water s edge (closest shoreline location) were measured. The Near tool in AGP was executed with the core point shapefile as input and line shapefile of the thalweg of each major tidal creek. The shortest distance between each core point and three tidal creeks was added to core point shapefile as distance to Bayou Heron, distance to Middle Bayou, and distance to Bayou Cumbest. Similarly, the Near tool was run between the core site and the shoreline shapefile and added to the core point shapefile as distance to water s edge. The resultant point shapefile was exported as a comma-separated values (.csv) file. The CSV file was modified in Microsoft Excel to include the following attributes: altFAN, SiteID, UTMxNAD83, UTMyNAD83, dGPS elevation, peat thickness, base peat, marsh width, bearing of marsh transect, distance to shoreline, distance to upland, distance to water's edge, distance to Bayou Heron, distance to Middle Bayou, and distance to Bayou Cumbest. All distance metrics are in meters. Person who carried out this activity:
   

   U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center

   Attn: Christopher G. Smith

   Research Geologist

   600 4th Street South

   St. Petersburg, FL
   

   U.S.

   (727) 502-8000 (voice)

   cgsmith@usgs.gov

   Data sources used in this process:

   • Terrano and others (2018)

   Data sources produced in this process:

   • PeatThickness_SiteInfo.csv

3. What similar or related data should the user be aware of?
   Marot, M.E., Kelso, K.W., Osterman, L.E., DeWitt, N.T., and Smith, C.G., 20180713, Sedimentary data collected in April 2013 from Dauphin Island and salt marshes of coastal Alabama: U.S. Geological Survey, St. Petersburg, Florida.

   Online Links:

   • https://doi.org/10.5066/F7H70DSZ

   Other_Citation_Details:

   Contains 13BIM01 site information, sediment physical properties, grain-size, gamma spectroscopy, foraminifera, stable isotope, element concentration and core data.

   Marot, M.E., Smith, C.G., McCloskey, T.A., Locker, S.D., Khan, N.S., and Smith, K.E.L., 20190301, Sedimentary data from Grand Bay, Alabama/Mississippi, 2014 2016 (ver. 1.1, April 2020): U.S. Geological Survey, St. Petersburg, Florida.

   Online Links:

   • https://doi.org/10.5066/P9FO8R3Y

   Other_Citation_Details:

   Contains 14CCT01, 16CCT03, 16CCT07 and other FAN data not directly associated with this data release. Data types include site information, sediment physical properties, grain-size, gamma and alpha spectroscopy, foraminifera, stable isotope, IPC-AES, radiocarbon, XRF, CTD, and core data.

   Kathryn E.L. Smith, Joseph F. Terrano, Jonathan Pitchford, Michael Brochard, Joseph M. Vargas, Isabelle D. Atchia, Cheyenne S. Everhart, and Christopher G. Smith, 20200713, Shore proximal marsh sediment deposition and ancillary data from Grand Bay National Estuarine Research Reserve, Mississippi, from July 2018 to January 2020 (ver. 2.0, June 2023): U.S. Geological Survey, St. Petersburg, Florida.

   Online Links:

   • https://doi.org/10.5066/P9ONI8PS

   Other_Citation_Details:

   Contains data from a related NST study in Point aux Chenes areas of the GNDNERR.

   Ellis, A.M., Smith, C.G., Vargas, J.M., and Everhart, C.S., 20220418, Sediment and radiochemical characteristics from a shore perpendicular estuarine and marsh transect in the Grand Bay National Estuarine Research Reserve, Mississippi: U.S. Geological Survey, St. Petersburg, Florida.

   Online Links:

   • https://doi.org/10.5066/P9BLFW2G

   Other_Citation_Details:

   Contains data from a related surface sample study in the Middle Bay area of the GNDNERR.

   Smith, C.G., Bernier, J., Ellis, A.M., and Smith, K.E.L., 20241219, Predictive regressive models of recent marsh sediment thickness improve the quantification of coastal marsh sediment budgets.: Elsevier, Online.

   Online Links:

   • https://doi.org/10.1016/j.acags.2024.100215

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

1. How well have the observations been checked?
   Location accuracy for each site/FAN is listed in its original data release, refer to those publication for more information. Peat thickness was measured in the field to the nearest 1-centimeter (cm).
2. How accurate are the geographic locations?
   
3. How accurate are the heights or depths?
   
4. Where are the gaps in the data? What is missing?
   This data release contains peat thickness data collected in Grand Bay, Mississippi and Alabama that has not been previously published in a USGS data release (referenced above).
5. How consistent are the relationships among the observations, including topology?
   This dataset includes site locations, Universal Transverse Mercator (UTM) x and y planar coordinates in meters, orthometric elevations/heights, observed peat thickness, the distance from the core site to both the upland boundary and shoreline, and the angle along the marsh transects, width along the marsh transect, as well as distances (only) for water's edge, Bayou Heron, Middle Bayou, and Bayou Cumbest for the following USGS assigned alternate FANs: 13BIM01, 14CCT01, 16CCT03, 16CCT07, 17CCT02, and 18CCT01.

How can someone get a copy of the data set?

1. Who distributes the data set? (Distributor 1 of 1)
   
   U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center

   Attn: USGS SPCMSC Data Management

   600 4th Street South

   Saint Petersburg, FL
   

   United States

   727-502-8000 (voice)

   gs-g-spcmsc_data_inquiries@usgs.gov
2. What's the catalog number I need to order this data set? PeatThickness_SiteInfo.csv
3. What legal disclaimers am I supposed to read?
   Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data for other purposes, nor on all computer systems, nor shall the act of distribution constitute any such warranty. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
4. How can I download or order the data?
   • Availability in digital form:

     Data format:	comma-delimited text (version 1.0) WinZip,7-zip
     Network links:	https://coastal.er.usgs.gov/data-release/doi-P13BDDHQ/data/PeatThickness_SiteInfo.zip

   • Cost to order the data: None

5. Is there some other way to get the data?
   None

Who wrote the metadata?

Dates:

Last modified: 20-Dec-2024

Metadata author:

U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center

Attn: USGS SPCMSC Data Management

600 4th Street South

St. Petersburg, FL

U.S.

(727) 502-8000 (voice)

gs-g-spcmsc_data_inquiries@usgs.gov

Metadata standard:

Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)