Noreen A. Buster William R. Pfeiffer Jennifer L. Miselis Jack L. Kindinger Dana S. Wiese U.S. Geological Survey 20110131 raster digital data USGS Data Series Publication DS739 http://pubs.usgs.gov/ds/739 http://pubs.usgs.gov/ds/739/Data_downloads_Cat.html In September and October of 2010, the U.S. Geological Survey (USGS), in cooperation with the Army Corps of Engineers (USACE), conducted geophysical surveys around Cat Island, Miss. to collect bathymetry, acoustical backscatter, and seismic reflection data (seismic-reflection data have been published separately, Forde and others, 2012). The geophysical data along with sediment vibracore data (yet to be published) will be integrated to analyze and produce a report describing the geomorphology and geologic evolution of Cat Island. Interferometric swath bathymetry, and acoustical backscatter data were collected aboard the RV G.K. Gilbert during the first cruise which took place September 7-15, 2010. Single-beam bathymetry was collected in very shallow water around the island aboard the RV Streeterville from September 28 through October 2, 2010 to bridge the gap between the landward limit of the previous cruise and the shoreline. The survey area extended from the nearshore to approximately 5 kilometers (km) offshore to the north, south, and west, and approximately 2 km to the east. This report archives bathymetry and acoustical backscatter data and provides information and mapping products essential for completion of the project goals. In order to comprehend seafloor surface lithology; acoustic backscatter mosaics, such as the data herein, are used as an aid in determining seafloor material types and extents. The file containing the backscatter data is a 1m GeoTIFF raster data set. These geophysical surveys will provide the data necessary for scientists to define, interpret, and provide acoustic backscatter data for interpretation of sea floor substrate and habitat. Additionally they will aid scientists in proposing theories on future geomorphological changes of the islands with respect to climate change, storm impact, and sea-level rise. Furthermore, these data will provide information for barrier island restoration, anthropogenic effects, and sediment distribution. The dataset herein is a complete side-scan sonar backscatter image for the study area offshore of the above-mentioned area. For more information refer to http://ngom.usgs.gov/gomsc/mscip/index.html. The U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center assigns a unique identifier to each cruise or field activity. For example, 10BIM04 tells us the data were collected in 2010 (10) for the Barrier Island Monitoring (BIM) study and the data were collected during the fourth (04) field activity for that project in that calendar year. Refer to <http://walrus.wr.usgs.gov/infobank/programs/html/definition/activity.html> for a detailed description of the method used to assign the field activity ID. Data were collected using the USGS research vessel R/V Gilbert. Side-scan sonar and interferometric swath bathymetry data were collected simultaneously along the tracklines during the geophysical operations. The side-scan sonar tow fish was flown off the port quarter, astern of the vessel. The interferometric swath transducer was pole-mounted off the starboard quarter of the research vessel. Navigation was acquired with a Coda Octopus F190 Precision Attitude and Positioning System and differentially corrected with OmniSTAR HP DGPS constellation. See the digital FACS equipment log for details about the acquisition equipment used. Both raw datasets were stored digitally and processed using SonarPro and CARIS HIPS and SIPS software version 7.1 in the USGS St. Petersburg office. For more information on processing, refer to the Equipment and Processing page. Chirp seismic reflectivity data were also collected during this survey and are archived separately. 20100907 20100915 ground condition Complete As needed -88.485858 -88.171679 30.254499 30.101438 USGS Metadata Identifier USGS:64f1072c-69a8-4233-a7f3-051dc36344a9 ISO 19115 Topic Category oceans and coastal geoscientific information None side scan swath backscatter sonar St. Petersburg Coastal and Marine Science Center USGS CMGP coastal and marine geology U.S. Geological Survey SPCMSC acoustic Data Categories for Marine Planning distributions bathymetry and elevation USGS Thesaurus interferometric sonar bathymetry measurement bathymetry marine geophysics Geographic Names Information System United States of America (USA) Cat Island Pass Mississippi Gulf Islands National Seashore Cat Island None sediment geology barrier island sea floor None 2010 September none These data should not be used for navigational purposes. The U.S. Geological Survey requests that it be referenced as the originator of this data set in any future products or research derived from these data. U.S. Geological Survey Jack Kindinger Research Geologist mailing

600 4th Street South

St. Petersburg Florida 33701 United States (727) 803-8747 jkindinger@usgs.gov U.S. Geological Survey Microsoft Windows 7 Version 6.1 (Build 7600) ; ESRI ArcGIS 10.0.4.4000 The accuracy of the data is determined during data collection. This dataset is from a single cruise and therefore internally consistent. Methods are employed to maintain data collection consistency aboard various platforms. During mobilization, each piece of equipment (swath and sonar) is isolated to obtain internal and external offset measurements with respect to the survey platform. All the critical measurements are recorded manually and digitally and entered into their respective programs for calibration. Once calibration status is considered acceptable, then survey operations commence. Each system has a dedicated computer, and efforts are made to utilize the same equipment and software versions. However, upgrades and changes occur and require additional setup, measurements, and notation. The swath transducer sonar head was pole-mounted on the starboard side of the vessel. Offsets between the sonar head and the Differential Global Positioning System (DGPS) antennas were measured and entered into the F190 internal setup program. DGPS is normally provided through the OmniSTAR High Performance wide-area GPS service unless otherwise noted. This dataset was completed on a single and continuous cruise over 4 days from the same research vessel platform. There may in some cases be data missing and inconsistent with reported tracklines. This is directly due to the exclusion of poor data, instrument failures, or maybe for the sake of consistent spatial resolution. The ship was navigated using the Coda Octopus F190 Precision Attitude and Positioning System. The software used is the F180 Series version 4.0.5. Two antennas received the integrated OmniSTAR High Performance DGPS correction. The software used is F180 Series version 4.0.5. The horizontal accuracy of bathymetric data is at the limit of OmniSTAR, a wide-area differential GPS service, which is within 20 cm. Unless noted, all DGPS data are referenced to WGS84. The swath transducer sonar head was pole-mounted off the starboard quarter of the vessel. Offsets between the sonar head and the DGPS antennas were measured and entered into the F190 internal calibration and setup program. 20 centimeters Side-scan data acquisition was at sea, collected with a Klein 3900 dual-frequency towfish flown port-quarter of the RV Gilbert. Data were acquired using SonarPro v.11.3 during a cruise in September 2010. Data were collected along planned tracklines approximately 150 meters apart at an average vessel speed of 4 knots. Navigation was calculated by means of DGPS satellite constellation position feed. Navigation data acquisition was at sea, collected with a real-time DGPS system aboard the RV Gilbert. Navigation data were collected in a hydrographic survey software application along planned tracklines approximately 150 meters apart at an average vessel speed of 4 knots. 20100601 Jacobs Technology William R. Pfeiffer Data Modeler mailing

600 4th Street South

St. Petersburg Florida 33701 (727) 803-8747 wpfeiffer@usgs.gov Within CARIS SIPS v7.0 data were converted from .xtf format to digitize altitude, filter speckle noise, and apply AVG and TVG corrections. The corrected lines were then used to create Georeferenced Backscatter Rasters (GeoBARs), which were fully blended into a 1 meter/pixel resolution composite mosaic. A complete GeoTIFF was then exported for use in a GIS. 20100601 Jacobs Technology William R. Pfeiffer Data Modeler mailing

600 4th Street South

St. Petersburg Florida 33701 (727) 803-8747 wpfeiffer@usgs.gov Keywords section of metadata optimized for discovery in USGS Coastal and Marine Geology Data Catalog. 20170214 U.S. Geological Survey Alan O. Allwardt Contractor -- Information Specialist mailing and physical address

2885 Mission Street

Santa Cruz CA 95060 831-460-7551 831-427-4748 aallwardt@usgs.gov Added keywords section with USGS persistent identifier as theme keyword. 20201013 U.S. Geological Survey VeeAnn A. Cross Marine Geologist Mailing and Physical

384 Woods Hole Road

Woods Hole MA 02543-1598 508-548-8700 x2251 508-457-2310 vatnipp@usgs.gov Raster Pixel 30085 31919 1 Transverse Mercator 0.9996 -87.0 0.0 500000.0 0.0 coordinate pair 0.5 0.5 meter D WGS 1984 WGS 1984 6378137.0 298.257223563 Image pixel values contain acoustic reflectivity values normalized to an 8-bit digital number range (0-255). Lower pixel intensity values correlate with lower signal loss in decibels. The background color is depicted at pixel value 255. GeoTIFF imagery is three bands with pixel values 0 to 255. U.S. Geological Survey U.S. Geological Survey Information Services mailing

Box 25286, Federal Center

Denver CO 80225-0046 U.S. 1-888-ASK-USGS infoservices@usgs.gov This DVD 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. GeoTIFF 294 http://pubs.usgs.gov/ds/739/ None Publications are available from U.S. Geological Survey Information Services, Box 25286, Federal Center, Denver, CO 80225-0046 (telephone: 1-888-ASK-USGS, e-mail: infoservices@usgs.gov). 20210922 Jacobs Technology William R. Pfeiffer Data Modeler mailing and physical

600 Fourth St. South

St. Petersburg Florida 33701 (727) 803-8747 wpfeiffer@usgs.gov FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998 local time None Unclassified None