Metadata: Identification_Information: Citation: Citation_Information: Originator: Alisha M. Ellis Originator: Christopher G. Smith Originator: Joseph M. Vargas Originator: Cheyenne S. Everhart Publication_Date: 20230823 Title: Sedimentologic Data from Point aux Chenes Marsh and Estuary, Mississippi (21CCT02) Edition: 1.0 Geospatial_Data_Presentation_Form: Multimedia presentation Larger_Work_Citation: Citation_Information: Originator: Alisha M. Ellis Originator: Christopher G. Smith Originator: Joseph M. Vargas Originator: Cheyenne S. Everhart Publication_Date: 20210605 Title: Sedimentologic Data from Point aux Chenes Marsh and Estuary, Mississippi Edition: 2.0 Series_Information: Series_Name: U.S. Geological Survey data release Issue_Identification: doi:10.5066/P9XYDHFZ Publication_Information: Publication_Place: St. Petersburg, Florida Publisher: U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center Online_Linkage: https://doi.org/10.5066/P9XYDHFZ Description: Abstract: Sediment samples, including marsh and estuarine surface samples and marsh push and peat-auger cores, were collected from Point aux Chenes, Mississippi from October 23-26, 2018, and August 4, 2021. Marsh surface samples (top 1 centimeter (cm) of sediment; sample names appended with S), marsh push cores (core names appended with M) and peat-auger cores (core names appended with R) were collected along 50-meter (m), shore perpendicular, transects identified as sites 5, 6, 7, and 9. All samples in the dataset are referred to by alternate field activity number (FAN) 18CCT09 (FAN 2018-358-FA) and alternate FAN 21CCT02 (FAN 2021-320-FA). Estuarine PONAR grab samples (sample names appended with G), marsh surface samples, and push cores were collected and brought back for sedimentological analyses including dry bulk density, organic content, grain-size for the development of a sedimentological baseline, and gamma spectroscopy for the development of geochronologies. Peat augers were collected, described for depth to peat, and discarded in the field. Marsh and estuarine surface and core sediment samples are part of the U.S. Geological Survey (USGS) St. Petersburg Coastal and Marine Science Center's (SPCMSC) Estuarine-MaRsh Geology (EMRG) and Sea-level and Storms Impacts on Estuarine Environments and Shorelines (SSIEES) research projects which study how and where short- and long-term marsh and estuarine coastal process interact in order to identify and evaluate geologic and geomorphic variables influences on marshes and their resiliency under different storm and sea-level scenarios, determine marsh-upland boundary change rates, and sediment accumulation and erosion rates. Note: This data release was revised on August 2, 2021, and versioned on August 23, 2023. Please see the Suggested Citation section on the data release webpage for more details. Purpose: Dissemination of processed sediment data from sediment surface and core samples collected from Point aux Chenes marsh and estuary, Mississippi (FAN 2018-358-FA and 2021-320-FA). Supplemental_Information: To ensure that USGS-SPCMSC data management protocols were followed, this survey was assigned the following USGS FAN: 2021-320-FA (Project ID/alternate FAN 21CCT02), 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=2022-302-FA. On August 4, 2021, two push cores and three peat augers from 2 unique sites were collected from the Point aux Chenes marsh 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 one base station. During field sampling, estuarine water parameter measurements were collected where applicable and are included in this report. Time_Period_of_Content: Time_Period_Information: Single_Date/Time: Calendar_Date: 20210804 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -88.45009 East_Bounding_Coordinate: -88.40274 North_Bounding_Coordinate: 30.36769 South_Bounding_Coordinate: 30.32135 Keywords: Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:b1e4e3e4-a47c-4bb8-ad12-39e6c272f05a Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificInformation Theme_Keyword: location Theme_Keyword: elevation Theme_Keyword: environment Theme_Keyword: biota Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: geology Theme_Keyword: rocks and deposits Theme_Keyword: unconsolidated deposits Theme_Keyword: wetland ecosystems Theme_Keyword: field sampling Theme_Keyword: push coring Theme_Keyword: augering Theme_Keyword: core analysis Theme_Keyword: porosity Theme_Keyword: bulk density Theme_Keyword: radioactivity Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: sediment Theme_Keyword: lithology Theme_Keyword: marsh core Theme_Keyword: loss on ignition Theme_Keyword: LOI Theme_Keyword: radiochemistry Theme_Keyword: gamma spectroscopy Theme_Keyword: 21CCT02 Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Place: Place_Keyword_Thesaurus: Geographic Names Information System (GNIS) Place_Keyword: Mississippi Place_Keyword: Gulf of Mexico Place_Keyword: Grand Bay Place_Keyword: Point aux Chenes 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. Point_of_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Alisha M. Ellis Contact_Position: Geologist Contact_Address: Address_Type: Mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: aellis@usgs.gov Data_Set_Credit: U.S. Geological Survey St. Petersburg Coastal and Marine Science Center Native_Data_Set_Environment: Dell Windows 10 Enterprise version 22H2; Microsoft Excel for Microsoft 365 MSO version 2208; VDatum version 3.6; GrafNav, version 8.7; iCRco QPC XSCAN32 version 2.10. Cross_Reference: Citation_Information: Originator: Cutshall, N.H., and Larsen, I.L. Publication_Date: 198607 Title: Calibration of a portable intrinsic Ge gamma-ray detector using point sources and testing for field applications Series_Information: Series_Name: Health Physics Issue_Identification: Volume 51 Other_Citation_Details: Pages 53-59 Online_Linkage: https://doi.org/10.1097/00004032-198607000-00004 Cross_Reference: Citation_Information: Originator: Osbourne, T.Z., and DeLaune R.D. Publication_Date: 20131018 Title: Soil and sediment sampling of inundated environments Series_Information: Series_Name: Methods in Biogeochemistry of Wetlands Issue_Identification: Volume 10 Other_Citation_Details: Pages 21-41 Online_Linkage: https://doi.org/10.2136/sssabookser10.c2 Cross_Reference: Citation_Information: Originator: Cutshall, N.H., Larsen, I.L., and Olsen, C.R. Publication_Date: 19830215 Title: Direct analysis of Pb-210 in sediment samples: self-absorption corrections Series_Information: Series_Name: Nuclear Instruments and Methods in Physics Research Issue_Identification: Volume 206, Issues 1-2 Other_Citation_Details: Pages 309-312 Online_Linkage: https://doi.org/10.1016/0167-5087(83)91273-5 Cross_Reference: Citation_Information: Originator: Dean, W.E. Publication_Date: 19740301 Title: Determination of carbonate and organic matter in calcareous sediments and sediment rocks by loss on ignition: comparison with other methods Series_Information: Series_Name: Journal of Sedimentary Petrology Issue_Identification: Volume 44, No. 1 Other_Citation_Details: Pages 242-248 Cross_Reference: Citation_Information: Originator: Nittrouer, C.A., Sternberg, R.W., Carpenter, R., and Bennett, J.T. Publication_Date: 197905 Title: The use of Pb-210 geochronology as a sedimentological tool: application to the Washington continental shelf Series_Information: Series_Name: Marine Geology Issue_Identification: Volume 31, Issues 3-4 Other_Citation_Details: Pages 297-316 Online_Linkage: https://doi.org/10.1016/0025-3227(79)90039-2 Cross_Reference: Citation_Information: Originator: Galle, O.K., and Runnels, R.T. Publication_Date: 19601201 Title: Determination of CO2 in carbonate rocks by controlled loss on ignition Series_Information: Series_Name: Journal of Sedimentary Petrology Issue_Identification: Volume 30, No. 4 Other_Citation_Details: Pages 613-618 Online_Linkage: https://doi.org/10.1306/74D70ABF-2B21-11D7-8648000102C1865D Cross_Reference: Citation_Information: Originator: Santisteban, J.I., Mediavilla, R., Lopez-Pamo, E., Dabrio, C.J., Blanca Ruiz Zapata, M., Garcia, M.J.G., Castano, S., and Martinez-Alfaro, P.E. Publication_Date: 200410 Title: Loss on ignition: a qualitative or quantitative method for organic matter and carbonate mineral content in sediments? Series_Information: Series_Name: Journal of Paleolimnology Issue_Identification: Volume 32 Other_Citation_Details: Pages 287-299 Online_Linkage: https://doi.org/10.1023/B:JOPL.0000042999.30131.5b Cross_Reference: Citation_Information: Originator: Wang, Q., Li, Y., and Wang, Y. Publication_Date: 201103 Title: Optimizing the weight loss-on-ignition methodology to quantify organic and carbonate carbon of sediments from diverse sources Series_Information: Series_Name: Environmental Monitoring and Assessment Issue_Identification: Volume 174 Other_Citation_Details: Pages 241-257 Online_Linkage: https://doi.org/10.1007/s10661-010-1454-z Cross_Reference: Citation_Information: Originator: Heiri, O., Lotter, A.F., and Lemcke, G. Publication_Date: 200101 Title: Loss on Ignition as a method for estimating organic and carbonate content in sediments: reproducibility and comparability of results Series_Information: Series_Name: Journal of Paleolimnology Issue_Identification: Volume 25 Other_Citation_Details: Pages 101-110 Online_Linkage: https://doi.org/10.1023/A:1008119611481 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The positional accuracy of the sample locations has a horizontal error of +/-8 millimeters (mm) + 0.5 parts per million (ppm) root mean square (RMS) and a vertical error of +/-15 mm + 0.5 ppm RMS. Replicate analyses of loss on ignition are reported for quality assurance. The gamma spectroscopic radioisotope activities reported include the counting error for all samples. The critical level for gamma spectroscopy is reported for each core set. Logical_Consistency_Report: Position and elevation data at each sample site were recorded with a Trimble R10 GNSS system set to 1 s continuous topo for shorelines and 10 s static occupations for all other data points. At the start of each survey a baseline mark was collected at the same location at the Grand Bay NERR headquarters. Completeness_Report: This data release (doi:10.5066/P9XYDHFZ) contains all sediment data associated with this USGS FAN and includes the geographic site location, sediment physical properties, and sediment radiochemistry activities for 2 cores collected at 2 sites on Point aux Chenes marsh and marsh surface and estuarine grab samples, collected in August 2021. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: +/-8 mm + 0.5 ppm RMS. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: +/-15 mm + 0.5 ppm RMS. Lineage: Process_Step: Process_Description: At 2 sites on the Point aux Chenes marsh, push cores (GB537M, GB572M) were collected with 10.16-cm diameter polycarbonate barrels. Upon retrieval, similar to methods described in Osbourne and DeLaune (2013; with the exception of not adding water for extraction when not necessary due to the sediments being saturated) and calculation of compaction due to coring, the cores were visually inspected for disturbances (i.e., 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. The cores were transported upright, in order to avoid slumping and preserve the natural sediment orientation, to the SPCMSC laboratory for sectioning. 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 (i.e., 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 logs, in centimeters. Once described and photographed horizontally with a scale bar and label, peat augers were discarded in the field. The field logs associated with those peat augers are available upon request. Sample identifiers consist of the USGS alternate FAN or project ID (21CCT02), a site-specific identifier (for example, GB572), and appended with an alphabetic identifier to differentiate the sediment collection method (M for marsh push core, R for Russian peat auger). Push core locations were initially recorded at the time of collection using a Garmin GPSMAP 76S or Garmin 62stc handheld GPS receiver. Marsh site coordinates were also recorded using a GPS antenna with base station set up. Site location information includes sample type, date collected, location relative to the shoreline, latitude, longitude, elevation, core lengths, and YSI measurements, 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. Process_Date: 2021 Source_Produced_Citation_Abbreviation: 21CCT02_SiteInformation.csv Source_Produced_Citation_Abbreviation: 21CCT02_SiteInformation.xlsx Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Joseph Terrano Contact_Position: Physical Scientist Contact_Address: Address_Type: Mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: (727) 502-8000 Contact_Electronic_Mail_Address: jterrano@usgs.gov Process_Step: Process_Description: DGPS Acquisition: A Trimble R10 GNSS and TSC3 data collector were used to collect global positioning system (GPS) coordinates and elevations. Both the R10 and TSC3 were mounted onto a 2-m graphite rod with a mounted foot to keep the rod on the surface of the marsh. A projected coordinate system (NAD_1983_StatePlane_Mississippi_East_FIPS_2301) was used for data collection. At marsh core sites, the "Measure Points" tool was used. Data were exported from the TSC3 as a shapefile (.shp). The .shp was pulled from the export folder and brought into ArcGIS software where the projection was defined as NAD_1983_StatePlane_Mississippi_East_FIPS_2301 (ESRI:102694). Process_Date: 2021 Source_Produced_Citation_Abbreviation: 21CCT02_SiteInformation.csv Source_Produced_Citation_Abbreviation: 21CCT02_SiteInformation.xlsx Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Joseph Terrano Contact_Position: Physical Scientist Contact_Address: Address_Type: Mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: (727) 502-8000 Contact_Electronic_Mail_Address: jterrano@usgs.gov Process_Step: Process_Description: GPS Post-Processing: Elevation data were sent to the USGS SPCMSC as ArcGIS shapefiles. Within ArcMap, the data were reprojected from NAD_1983_StatePlane_Mississippi_East_FIPS_2301 into NAD_1983_UTM_Zone_16N (North American Datum of 1983 Universal Transverse Mercator Zone 16 North), using the "reproject" geoprocessing tool. The final shapefile was exported into tabular digital data format (Comma Separated Values [CSV]). Process_Date: 2021 Source_Produced_Citation_Abbreviation: 21CCT02_SiteInformation.csv Source_Produced_Citation_Abbreviation: 21CCT02_SiteInformation.xlsx Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Joseph Terrano Contact_Position: Physical Scientist Contact_Address: Address_Type: Mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: (727) 502-8000 Contact_Electronic_Mail_Address: jterrano@usgs.gov Process_Step: Process_Description: Upon return from the field, all marsh push cores were X-rayed vertically using a stand, to avoid sediment slumping, 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 exported as Tag Image File Format (.tiff) files and edited in Adobe Photoshop, using grayscale color inversion, and inserting a reference scale bar. X-ray images were used as visual aids prior to extrusion and subsampling to assess peat thickness in comparison with peat augers, presence of macrofossils which may impede sectioning, and to ensure cores are intact for the length of the core. Process_Date: 2021 Source_Produced_Citation_Abbreviation: 18CCT09_21CCT02_Xrays.zip Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey St. Petersburg Coastal and Marine Science Center Contact_Person: Alisha M. Ellis Contact_Position: Geologist Contact_Address: Address_Type: Mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: U.S. Contact_Voice_Telephone: (727) 502-8000 Contact_Electronic_Mail_Address: aellis@usgs.gov Process_Step: Process_Description: Following x-raying, all cores were vertically extruded and sectioned into 1-cm intervals using a serrated knife, pre-measured polycarbonate ring, and extruder (in accordance with methods described in Osbourne and DeLaune, 2013 and in 1-cm intervals as is standard for sediment and radiochemical analyses; Nittrouer and others, 1979) at the USGS SPCMSC sediment core laboratory. The outer circumference of each sample interval was removed to avoid use of sediment that was in contact with the polycarbonate barrel which could result in contamination by sediment from other depths due to movement within the barrel both during collection and extruding; each sediment interval was bagged in a zipped baggie, homogenized, and refrigerated (Osbourne and DeLaune, 2013). Process_Date: 2021 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey St. Petersburg Coastal and Marine Science Center Contact_Person: Alisha M. Ellis Contact_Position: Geologist Contact_Address: Address_Type: Mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: U.S. Contact_Voice_Telephone: (727) 502-8000 Contact_Electronic_Mail_Address: aellis@usgs.gov Process_Step: Process_Description: In the laboratory, marsh core samples were homogenized in the sample bag to ensure a representative subsample from the 1-cm interval, 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. To calculate, 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/weigh boat, and the weight was recorded. The wet sediment sample and tray were placed in a drying oven for 48 hours at 60 °C to remove water content. A 1 mL split from the original wet sample was also taken for diatom analysis and was dried using the same procedure. Water content (θ) was determined as the mass of water (lost when dried) relative to the initial wet sediment mass. Porosity (φ) was estimated from the equation φ = θ / [θ+(1-θ)/ρs] where ρs is grain density assumed to be 2.5 grams per cubic centimeter (g/cm^3), representative of a silty quartz sand. 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 (.xlsx). A comma-separated values (.csv) data file containing the tabular data in plain text is included in the download file. Some depth intervals in the .csv file display as dates due to csv formatting. Process_Date: 2021 Source_Produced_Citation_Abbreviation: 21CCT02_SedimentPhysicalProperties.csv Source_Produced_Citation_Abbreviation: 21CCT02_SedimentPhysicalProperties.xlsx Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey St. Petersburg Coastal and Marine Science Center Contact_Person: Alisha M. Ellis Contact_Position: Geologist Contact_Address: Address_Type: Mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: U.S. Contact_Voice_Telephone: (727) 502-8000 Contact_Electronic_Mail_Address: aellis@usgs.gov Process_Step: Process_Description: Organic matter (OM) content was determined with a mass loss technique referred to as loss on ignition (LOI). The dry sediment subsample from the previous process step, measuring dry bulk density, was homogenized with a porcelain mortar and pestle. Approximately 2 to 6 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 (Celsius) 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 (modified from Dean, 1974 who heated the furnace to 100 °C for 1 hour). The dried sediment was returned to the muffle furnace and heated to 550 °C over a period of 30 minutes and kept at 550 °C (Galle and Runnels, 1960) for 6 hours (optimal exposure times for complete combustion of organic carbon are reported ranging between 1–12 hours; Dean, 1974; Wang and others, 2011; Heiri and others, 2001; Santisteban and others, 2004). Following the 6-hour burn time for removal of organic carbon, the furnace's temperature was lowered to 60 °C, at which point the sediments could be reweighed safely while preventing the absorption of moisture, which can affect the measurement. The mass lost during the 6-hour baking period relative to the 110 °C-dried mass is used as a metric of OM content (Dean, 1974). Approximately 12.3 percent of the field samples were run in triplicate 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 (.xlsx). A comma-separated values (.csv) data file containing the tabular data in plain text is included in the download file. Some depth intervals in the .csv file display as dates due to csv formatting. Process_Date: 2023 Source_Produced_Citation_Abbreviation: 21CCT02_SedimentPhysicalProperties.csv Source_Produced_Citation_Abbreviation: 21CCT02_SedimentPhysicalProperties.xlsx Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey St. Petersburg Coastal and Marine Science Center Contact_Person: Alisha M. Ellis Contact_Position: Geologist Contact_Address: Address_Type: Mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: U.S. Contact_Voice_Telephone: (727) 502-8000 Contact_Electronic_Mail_Address: aellis@usgs.gov Process_Step: Process_Description: Dried, ground sediment from the 1-cm depth intervals of 2 push cores were analyzed for the detection of radionuclides by standard gamma-ray spectrometry (Cutshall and Larsen, 1986) at the USGS SPCMSC radioisotope lab. Intervals from the uppermost 40 cm were analyzed from each core. The sediments were sealed in airtight polypropylene containers for planar detectors or polystyrene test tubes for the well detector. Sediments placed in the test tubes were sealed with a layer of epoxy. The sample weights and counting container geometries were matched to pre-determined calibration standards. 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 daughter isotopes lead-214 (Pb-214) and bismuth-214 (Bi-214). The sealed samples were then counted for 48-72 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 Pb-210 (46.5 keV), thorium-234 (Th-234; 63.3 keV), Pb-214 (295.7 and 352.5 keV; proxies for Ra-226), 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 (.xlsx) include the counting error for all samples, results from each core are on its own tab. The critical level is reported for each core. A comma-separated values (.csv) data file containing the tabular data in plain text is included in the download file. Some depth intervals in the .csv file display as dates due to csv formatting. Process_Date: 2023 Source_Produced_Citation_Abbreviation: 21CCT02_GammaSpectroscopy.csv Source_Produced_Citation_Abbreviation: 21CCT02_GammaSpectroscopy.xlsx Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey St. Petersburg Coastal and Marine Science Center Contact_Person: Marci E. Marot Contact_Position: Geologist Contact_Address: Address_Type: Mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: U.S. Contact_Voice_Telephone: (727) 502-8000 Contact_Electronic_Mail_Address: mmarot@usgs.gov Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: 18CCT09_SiteInformation.csv, 21CCT02_SiteInformation.xlsx Entity_Type_Definition: Comma-separated values text file (.csv) and Microsoft Excel workbook defining the field sampling dates, site locations, elevations, water depths, core lengths and compaction, and water quality parameters for the push cores collected in this study (USGS FAN 2021-320-FA, alternate FAN/project ID 21CCT02). Some values in the .csv file display as dates due to csv formatting, and no data values are indicated with a hyphen. Entity_Type_Definition_Source: USGS Attribute: Attribute_Label: Alternate FAN Attribute_Definition: Alternate field activity number assigned by the USGS to the sample collection. Attribute_Definition_Source: USGS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: 21CCT02 Enumerated_Domain_Value_Definition: Alternate FAN (FAN 2021-320-FA). Enumerated_Domain_Value_Definition_Source: USGS Attribute: Attribute_Label: Sample ID Attribute_Definition: Sample identifier assigned by USGS scientist consisting of GB to indicate Grand Bay and a three-digit number. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Character string Attribute: Attribute_Label: Sample Type Collected Attribute_Definition: Additional sample identifier designations appended to identify sample type collected at a single site. For some sites, multiple sample types were collected, which is designated by a letter and space between each sample type. Attribute_Definition_Source: USGS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: M Enumerated_Domain_Value_Definition: Marsh push core Enumerated_Domain_Value_Definition_Source: USGS Attribute_Domain_Values: Enumerated_Domain: Enumerated_Domain_Value: R Enumerated_Domain_Value_Definition: Russian peat auger core Enumerated_Domain_Value_Definition_Source: USGS Attribute: Attribute_Label: Transect Site ID Attribute_Definition: Marsh samples were collected along shore perpendicular transects, with each transect referred to as a site number. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Sample sites include Site 7 and 9. Attribute: Attribute_Label: Distance from Shoreline (m) Attribute_Definition: Distance, in meters, from the shoreline where the samples at that site were collected. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 20 Range_Domain_Maximum: 50 Attribute_Units_of_Measure: meters Attribute: Attribute_Label: Date Collected Attribute_Definition: Date identifier Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 08/04/21 Range_Domain_Maximum: 08/04/21 Attribute_Units_of_Measure: mm/dd/yy Attribute: Attribute_Label: Latitude (NAD83) Attribute_Definition: Latitude of station location, in decimal degrees (North American Datum of 1983). Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 30.33677 Range_Domain_Maximum: 30.34447 Attribute_Units_of_Measure: Decimal degrees Attribute_Measurement_Resolution: 0.00001 Attribute: Attribute_Label: Longitude (NAD83) Attribute_Definition: Longitude of site location, in decimal degrees (North American Datum of 1983). Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -88.44894 Range_Domain_Maximum: -88.44667 Attribute_Units_of_Measure: Decimal degrees Attribute_Measurement_Resolution: 0.00001 Attribute: Attribute_Label: Elevation (m, NAVD88 GEOID12A) Attribute_Definition: The elevation, in meters, of each site relative to the North American Datum of 1988 GEOID12A. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.325 Range_Domain_Maximum: 0.404 Attribute_Units_of_Measure: meters Attribute_Measurement_Resolution: 0.001 Attribute: Attribute_Label: Water Depth (m) Attribute_Definition: The depth of the water recorded at each estuarine site, in meters. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1.5 Range_Domain_Maximum: 1.5 Attribute_Units_of_Measure: meters Attribute_Measurement_Resolution: 0.1 Attribute: Attribute_Label: Field Estimated Recovered Core Length (cm) Attribute_Definition: The approximate length of the push core collected, in centimeters, as recorded in the field. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 28.2 Range_Domain_Maximum: 44.2 Attribute_Units_of_Measure: centimeters Attribute_Measurement_Resolution: 0.2 Attribute: Attribute_Label: Coring Compaction (cm) Attribute_Definition: The approximate amount of compaction withstood by the push core, in centimeters, as recorded in the field. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 2.7 Range_Domain_Maximum: 9.2 Attribute_Units_of_Measure: centimeters Attribute_Measurement_Resolution: 0.1 Attribute: Attribute_Label: Core Diameter (cm) Attribute_Definition: The diameter of the acrylic core barrel used to collect the push cores, in centimeters. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 10.16 Range_Domain_Maximum: 10.16 Attribute_Units_of_Measure: centimeters Attribute_Measurement_Resolution: 0.01 Attribute: Attribute_Label: Number Auger Sections (N) Attribute_Definition: The total number of 50-centimeter sections of Russian Peat Augers collected at each station. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 3 Range_Domain_Maximum: 4 Attribute_Units_of_Measure: Number of 50-centimeter sections Attribute_Measurement_Resolution: 1.0 Attribute: Attribute_Label: Recovered Auger Length (cm) Attribute_Definition: The total length of the Russian Peat Auger collected at each site in centimeters, as recorded in the field. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 109.0 Range_Domain_Maximum: 160.0 Attribute_Units_of_Measure: centimeters Attribute_Measurement_Resolution: 0.5 Attribute: Attribute_Label: Marsh Unit Thickness (cm) Attribute_Definition: The estimated vertical extent/depth of the marsh unit, in centimeters. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 109 Range_Domain_Maximum: 129 Attribute_Units_of_Measure: centimeters Attribute_Measurement_Resolution: 1.0 Attribute: Attribute_Label: Elevation of Basal Marsh Contact (m, NAVD88 GEOID12A) Attribute_Definition: The estimated elevation of the basal marsh contact, in meters, at each site relative to the North American Vertical Datum of 1988 GEOID12A. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -0.944 Range_Domain_Maximum: -0.746 Attribute_Units_of_Measure: meters Attribute_Measurement_Resolution: 0.001 Detailed_Description: Entity_Type: Entity_Type_Label: 21CCT02_SedimentPhysicalProperties.csv, 21CCT02_SedimentPhysicalProperties.xlsx Entity_Type_Definition: Comma-separated values text file (.csv) and Microsoft Excel workbook listing water content, porosity, dry bulk density (DBD) and loss-on-ignition (LOI) data for sediment cores collected on and around Point aux Chenes marsh, Mississippi (USGS FAN 2021-320-FA, alternate FAN/project ID 21CCT02). The results for each core are provided on its own tab. Some values in the .csv file display as dates due to csv formatting, and no data values are indicated with a hyphen. Entity_Type_Definition_Source: USGS Attribute: Attribute_Label: Core ID Attribute_Definition: Core identifier assigned by a USGS scientist. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Identifier consists of alternate FAN (21CCT02), hyphen, sample ID (GB####), hyphen, sample type (M = marsh push core), hyphen, PP (physical parameters subsample). A, B, and C indicate laboratory replicates of a single sample. Attribute: Attribute_Label: Depth (cm) Attribute_Definition: Depth interval in centimeters measured below the core surface, A, B, and C indicates laboratory replicate. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0-1 Range_Domain_Maximum: 40-41.2 Attribute_Units_of_Measure: centimeters Attribute_Measurement_Resolution: 0.2 Attribute: Attribute_Label: Water Content (g-water/g-wet) Attribute_Definition: The ratio of the mass of water to the mass of wet sediment. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.39 Range_Domain_Maximum: 0.76 Attribute_Units_of_Measure: Grams of water per grams of wet sediment Attribute_Measurement_Resolution: 0.01 Attribute: Attribute_Label: Dry Bulk Density (g/cm^3) Attribute_Definition: Dry bulk density of the sediment interval. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.25 Range_Domain_Maximum: 0.91 Attribute_Units_of_Measure: Grams per cubic centimeter Attribute_Measurement_Resolution: 0.01 Attribute: Attribute_Label: Loss On Ignition (g-OM/g-dry) Attribute_Definition: The ratio of the mass of organic matter combusted at 550 degrees Celsius to the pre-combusted mass of dry sediment. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.06 Range_Domain_Maximum: 0.79 Attribute_Units_of_Measure: Grams of organic matter per grams of dry sediment Attribute_Measurement_Resolution: 0.01 Detailed_Description: Entity_Type: Entity_Type_Label: 21CCT02_GammaSpectroscopy.csv, 21CCT02_GammaSpectroscopy.xlsx Entity_Type_Definition: Comma-separated values text file (.csv) and Microsoft Excel workbook summarizing the total cesium-137, lead-210, radium-226, thorium-234, potassium-40, and their associated errors for each depth interval for the sediment cores collected from the Point aux Chenes marsh, Mississippi (USGS FAN 2021-320-FA, alternate FAN/project ID 21CCT02). The results are provided for each core on its own tab. Some values in the .csv file display as dates due to csv formatting, no data values are indicated with a double hyphen, and values of ND indicate not detected. Entity_Type_Definition_Source: USGS Detailed_Description: Entity_Type: Entity_Type_Label: 21CCT02_GammaSpectroscopy.csv Entity_Type_Definition: Comma-separated values text file summarizing the total cesium-137, lead-210, radium-226, thorium-234, potassium-40, and their associated errors for each depth interval for the sediment cores collected from the Point aux Chenes marsh, Mississippi (USGS FAN 2021-320-FA, alternate FAN/project ID 21CCT02). Entity_Type_Definition_Source: USGS Attribute: Attribute_Label: Core ID Attribute_Definition: Core identifier assigned by a USGS scientist. Attribute_Definition_Source: USGS Attribute_Domain_Values: Unrepresentable_Domain: Identifier consists of alternate FAN (21CCT02), hyphen, sample ID (GB####), hyphen, sample type (M = marsh push core). Attribute: Attribute_Label: Depth (cm) Attribute_Definition: Depth interval in centimeters measured below the core surface. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0-1 Range_Domain_Maximum: 39-40 Attribute_Units_of_Measure: centimeters Attribute_Measurement_Resolution: 1.0 Attribute: Attribute_Label: Cs-137 (dpm/g) Attribute_Definition: The total activity of cesium-137 for each centimeter interval of every core in disintegrations per minute per gram of sediment. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.10 Range_Domain_Maximum: 1.30 Attribute_Units_of_Measure: Disintegrations per minute per gram Attribute_Measurement_Resolution: 0.01 Attribute: Attribute_Label: Cs-137 Error (+/- dpm/g) Attribute_Definition: The counting error associated with the total activity of cesium-137 for each centimeter interval for every core in disintegrations per minute per gram of sediment. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.04 Range_Domain_Maximum: 0.13 Attribute_Units_of_Measure: Disintegrations per minute per gram Attribute_Measurement_Resolution: 0.01 Attribute: Attribute_Label: Pb-210 (dpm/g) Attribute_Definition: The total activity of lead-210 for each centimeter interval of every core in disintegrations per minute per gram of sediment. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1.82 Range_Domain_Maximum: 8.34 Attribute_Units_of_Measure: Disintegrations per minute per gram Attribute_Measurement_Resolution: 0.01 Attribute: Attribute_Label: Pb-210 Error (+/- dpm/g) Attribute_Definition: 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. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.19 Range_Domain_Maximum: 0.39 Attribute_Units_of_Measure: Disintegrations per minute per gram Attribute_Measurement_Resolution: 0.01 Attribute: Attribute_Label: Ra-226 (dpm/g) Attribute_Definition: The total activity of radium-226 for each centimeter interval of every core in disintegrations per minute per gram of sediment. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1.17 Range_Domain_Maximum: 1.95 Attribute_Units_of_Measure: Disintegrations per minute per gram Attribute_Measurement_Resolution: 0.01 Attribute: Attribute_Label: Ra-226 Error (+/- dpm/g) Attribute_Definition: The counting error associated with the total activity of radium-226 for each centimeter interval for every core in disintegrations per minute per gram of sediment. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.07 Range_Domain_Maximum: 0.13 Attribute_Units_of_Measure: Disintegrations per minute per gram Attribute_Measurement_Resolution: 0.01 Attribute: Attribute_Label: Th-234 (dpm/g) Attribute_Definition: The total activity of thorium-234 for each centimeter interval of every core in disintegrations per minute per gram of sediment. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1.81 Range_Domain_Maximum: 7.27 Attribute_Units_of_Measure: Disintegrations per minute per gram Attribute_Measurement_Resolution: 0.01 Attribute: Attribute_Label: Th-234 Error (+/- dpm/g) Attribute_Definition: The counting error associated with the total activity of thorium-234 for each centimeter interval for every core in disintegrations per minute per gram of sediment. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.23 Range_Domain_Maximum: 0.52 Attribute_Units_of_Measure: Disintegrations per minute per gram Attribute_Measurement_Resolution: 0.01 Attribute: Attribute_Label: K-40 (dpm/g) Attribute_Definition: The total activity of potassium-40 for each centimeter interval of every core in disintegrations per minute per gram of sediment. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 4.68 Range_Domain_Maximum: 22.09 Attribute_Units_of_Measure: Disintegrations per minute per gram Attribute_Measurement_Resolution: 0.01 Attribute: Attribute_Label: K-40 Error (+/- dpm/g) Attribute_Definition: The counting error associated with the total activity of potassium-40 for each centimeter interval for every core in disintegrations per minute per gram of sediment. Attribute_Definition_Source: USGS Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.78 Range_Domain_Maximum: 1.79 Attribute_Units_of_Measure: Disintegrations per minute per gram Attribute_Measurement_Resolution: 0.01 Overview_Description: Entity_and_Attribute_Overview: The processed x-ray images of each marsh push core are provided for non-quantitative purposes only (18CCT09_21CCT02_Xrays.zip). Entity_and_Attribute_Detail_Citation: Core x-radiographic images (.jpg) provided in, in: Ellis, A.M., Smith, C.G., Vargas, J., and Everhart, C., 2021, Sedimentologic Data from Point aux Chenes Marsh and Estuary, Mississippi, (ver. 2.0, August 2023), https://doi.org/10.5066/P9XYDHFZ. Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey, St. Petersburg Coastal and Marine Science Center Contact_Person: Alisha M. Ellis Contact_Position: Geologist Contact_Address: Address_Type: Mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: aellis@usgs.gov Resource_Description: 21CCT02_SiteInformation.csv, 21CCT02_SiteInformation.xlsx, 21CCT02_SedimentPhysicalProperties.csv, 21CCT02_SedimentPhysicalProperties.xlsx, 21CCT02_GammaSpectroscopy.csv, 21CCT02_GammaSpectroscopy.xlsx, 21CCT02-GB537M_xray.jpg, and 21CCT02-GB572M_xray.jpg Distribution_Liability: 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. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: Compressed (zip) archive Format_Version_Date: 2023 Format_Specification: WinZip, 7-Zip Format_Information_Content: This zip archive includes Microsoft Excel spreadsheets (.xlsx), comma-separated values text files (.csv), Joint Photographic Experts Group files (JPEG) and accompanying metadata for sediment data from cores collected from the Point aux Chenes marsh (USGS FAN 2021-320-FA). File_Decompression_Technique: Unzip Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P9XYDHFZ/data/18CCT09_21CCT02_SiteInformation.zip Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P9XYDHFZ/data/18CCT09_21CCT02_SedimentPhysicalProperties.zip Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P9XYDHFZ/data/18CCT09_21CCT02_GammaSpectroscopy.zip Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P9XYDHFZ/data/18CCT09_21CCT02_FieldLogs.zip Network_Resource_Name: https://coastal.er.usgs.gov/data-release/doi-P9XYDHFZ/data/18CCT09_21CCT02_Xrays.zip Fees: None, if obtained online Technical_Prerequisites: The data tables for USGS FAN 2021-320-FA were created in Microsoft Excel and can be opened using Microsoft Excel 2007 or higher. 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. Metadata_Reference_Information: Metadata_Date: 20230823 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Alisha M. Ellis Contact_Position: Geologist Contact_Address: Address_Type: Mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: 727-502-8000 Contact_Electronic_Mail_Address: aellis@usgs.gov Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Access_Constraints: None Metadata_Use_Constraints: Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Metadata_Security_Information: Metadata_Security_Classification_System: None Metadata_Security_Classification: Unclassified Metadata_Security_Handling_Description: None