Marci E. Marot 20170315 Tabular digital data Marci E. Marot Christopher G. Smith C. Scott Adams Kathyrn A. Richwine 20170315 Multimedia presentation U.S. Geological Survey Data Series 1045 St. Petersburg, FL U.S. Geological Survey https://doi.org/10.3133/ds1045 Scientists from the U.S. Geological Survey (USGS), St. Petersburg Coastal and Marine Science Center collected a set of sediment cores from the back-barrier environments along the Chandeleur Islands, Louisiana, in March 2012. The sampling efforts were part of a larger USGS study to evaluate effects on the geomorphology of the Chandeleur Islands following the construction of an artificial sand berm to reduce oil transport onto federally managed lands. The objective of this study was to evaluate the response of the back-barrier tidal and wetland environments to the berm. This report serves as an archive for sedimentological and radiochemical data derived from the sediment cores. The data described in this report is available for download. The Site_Locations.xlsx file includes sampling date, core location coordinates and elevation for sampling sites occupied on the Chandeleur Islands, Louisiana in March 2012 by the USGS, St. Petersburg Coastal and Marine Science Center. None 20120324 20120326 Ground condition Complete None planned -88.836353 -88.824796 29.969588 29.895421 ISO 19115 Topic Category geoscientificInformation biota oceans USGS Thesaurus geology geochemistry unconsolidated deposits None back-barrier estuaries wetland sediment latitude longitude easting northing elevation U.S. Geological Survey USGS U.S. Geological Survey St. Petersburg Coastal and Marine Science Center Geographic Names Information System (GNIS) Louisiana Gulf of Mexico Chandeleur Islands None sediment subsurface None March 2012 None 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. U.S. Geological Survey Marci Marot Geologist Mailing and physical

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St. Petersburg FL 33701 USA (727) 502-8000 mmarot@usgs.gov U.S. Geological Survey, Coastal and Marine Geology Program, St. Petersburg Coastal and Marine Science Center Microsoft Windows 7 Enterprise Service Pack 1 The positional accuracy of the sample locations was determined by the accuracy of the raw position data recorded by the GPS antenna during data collection. Differential Geographic Positioning System (DGPS) coordinates were obtained using post-processing software packages (National Geodetic Survey's On-Line Positioning User Service (OPUS), version 2.2 and Waypoint Product Group's GrafNav and GrafNet, version 8.30). This dataset contains the post-processed DGPS coordinates for samples collected during May 2012. This is a complete processed location and elevation data file for the 12BIM01 sediment data archive. All static base station sessions were processed through the On-Line Positioning User Service (OPUS) maintained by the National Oceanic and Atmospheric Administration (NOAA) and the National Geodetic Survey (NGS), and the results were entered into a spreadsheet to compute a final, time-weighted positional coordinate (latitude, longitude, and ellipsoid height). Base-station positional error for each GPS session was calculated as the absolute value of the final position minus the session position value. The maximum horizontal error of the base station coordinates used for post-processing the sample locations was 0.00018 seconds latitude and 0.00045 seconds longitude. All static base station sessions were processed through OPUS maintained by the National Oceanic and Atmospheric Administration (NOAA) and the National Geodetic Survey (NGS). The base location results from OPUS were entered into a spreadsheet to compute a final, time-weighted positional coordinate (latitude, longitude, and ellipsoid height). Base-station positional error for each GPS session was calculated as the absolute value of the final position minus the session position value. For this survey, the standard deviation or the base station ellipsoid height was 0.006 m and the maximum vertical error for the base station was +/- 0.021 m. All sample locations were post-processed to the base station coordinates. Accurate position and elevation data were obtained at all sampling locations with an Ashtech Differential Global Positioning System (DGPS) receiver and antenna with occupation times of 30 minutes. A GPS base station was erected at a temporarily installed USGS benchmark (TMRK) located on the sound side of the Chandeleur Islands within about 6 km of the furthest sample site. GPS receivers recorded the 12-channel full-carrier-phase positioning signals (L1/L2) from satellites via the Thales choke-ring antenna. This GPS instrument combination was duplicated on the rover GPS. The base receiver and the rover receiver record their positions concurrently at 1-second (s) recording intervals throughout the survey. Occupation times at the sample sites ranged from 5 to 30 minutes. 2012 U.S. Geological Survey Marci Marot Geologist Mailing and physical

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St. Petersburg FL 33701 USA (727) 502-8000 mmarot@usgs.gov The coordinate values of the GPS base station (TMRK) are the time-weighted average of values obtained from the National Geodetic Survey On-Line Positioning User Service (OPUS). The base station coordinates were imported into GrafNav and GrafNet, version 8.3 (Waypoint Product Group) and the GPS data from the rover were post-processed to the concurrent GPS session data at the base station. The GPS data were processed and exported in the World Geodetic System of 1984 (WGS84) (G1150) geodetic datum. 2012 U.S. Geological Survey Marci Marot Geologist Mailing and physical

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St. Petersburg FL 33701 USA (727) 502-8000 mmarot@usgs.gov Sample locations were transformed from the GPS acquisition datum (WGS84) to the North American Datum of 1983 (NAD83), and the North American Vertical Datum of 1988 (NAVD88) orthometric elevation (geoid model of 2009, GEOID09) using NOAA VDatum version 3.2 transformation software (http://vdatum.noaa.gov/) and imported into Esri ArcGIS version 10.1. 2013 U.S. Geological Survey Marci Maro Geologist Mailing and physical

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St. Petersburg FL 33701 USA (727) 502-8000 Vector Point 8 Universal Transverse Mercator 16 0.9996 87.0 0.0 500000.0 0.0 coordinate pair 0.001 0.001 Meters North American Datum of 1983 GRS 1980 6378137.0 298.257222101 North American Vertical Datum of 1988 0.001 Meters Attribute values Site_Location.xlsx Micr0soft Excel workbook defining the location of sediment samples collected in March 2012 from the northern Chandeleur Islands, Louisiana (U.S. Geological Survey Field Activity Number 12BIM01) USGS Core ID Core identification number USGS Core site identification number assigned by USGS scientist Sampling Date Date core was collected USGS 3/24/2012 3/26/2012 mm/dd/yyyy 1 day Latitude Latitude of sample location in decimal degrees (NAD83) USGS 29.89559 29.96950 decimal degrees 0.00001 Longitude Longitude of sample location in decimal degrees (NAD83) USGS -88.83258 -88.82502 decimal degrees 0.00001 Easting (m) X-coordinate (easting) of sample location in meters (NAD83, UTM Zone 16N) USGS 323182.483 323803.558 Meters 0.001 Northing (m) Y-coordinate (northing) of sample location in meters (NAD83, UTM Zone 16N) USGS 3308617.196 3316818.387 Meters 0.001 Elevation (m) Elevation of sample location in meters (NAVD88, GEOID09) USGS -0.010 0.374 Meters 0.001 U.S. Geological Survey Marci Marot Geologist Mailing and physical

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St. Petersburg FL 33701 USA (727) 502-8000 mmarot@usgs.gov Downloadable data Although these data have been processed successfully on a computer system at the U.S. Geological Survey (USGS), 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 USGS or U.S. Government shall not be held liable for improper or incorrect use of the data described and (or) contained herein. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Microsoft Excel 2010 This Microsoft Excel workbook contains site locations for sediment samples collected in March 2012 (USGS Field Activity Number 12BIM01). None 0.010 https://pubs.usgs.gov/ds/1045/downloads/Site_Locations.xlsx None, if obtained online This workbook was created using Microsoft Excel 2010 and can be opened using Microsoft Excel 2007 or higher; these data may also be viewed using the free Microsoft Excel Viewer (http://www.microsoft.com/). 20170315 U.S. Geological Survey Marci Marot Geologist Mailing and physical

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St. Petersburg FL 33701 USA (727) 502-8000 mmarot@usgs.gov Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998 None Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. None Unclassified None