In March of 2010, the U.S. Geological Survey (USGS) conducted geophysical surveys east of Cat Island, Mississippi. The efforts were part of the USGS Gulf of Mexico Science Coordination partnership with the U. S. Army Corps of Engineers (USACE) to assist the Mississippi Coastal Improvements Program (MsCIP) and the Northern Gulf of Mexico (NGOM) Ecosystem Change and Hazards Susceptibility Project by mapping the shallow geological stratigraphic framework of the Mississippi Barrier Island Complex. The data collected will be used to create baseline bathymetry information that will address seafloor change. This report contains swath bathymetry and side scan sonar data collected aboard the R/V Survey Cat during Cruise 10CCT01. A combination of software packages was used to process and grid the data. This data series describes the methodology used and the resulting data projects.

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. The bathymetry will provide elevations and show geomorphic characteristics of the seafloor, while the backscatter and acoustical backscatter imagery will enhance the geomorphic characteristics and give insight to variations of sediment types on the seafloor. This file contains the trackline locations and names of the single-beam bathymetry around Cat Island, Miss.

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. The bathymetry will provide elevations and show geomorphic characteristics of the seafloor, while the backscatter and acoustical backscatter imagery will enhance the geomorphic characteristics and give insight to variations of sediment types on the seafloor. This file contains the trackline locations and names for swath bathymetry and acoustic backscatter data around Cat Island, Miss.

In March of 2010, the U.S. Geological Survey (USGS) conducted geophysical surveys east of Cat Island, Mississippi. The efforts were part of the USGS Gulf of Mexico Science Coordination partnership with the U. S. Army Corps of Engineers (USACE) to assist the Mississippi Coastal Improvements Program (MsCIP) and the Northern Gulf of Mexico (NGOM) Ecosystem Change and Hazards Susceptibility Project by mapping the shallow geological stratigraphic framework of the Mississippi Barrier Island Complex. The data collected will be used to create baseline bathymetry information that will address seafloor change. This report contains swath bathymetry and side scan sonar data collected aboard the R/V Survey Cat during Cruise 10CCT01. A combination of software packages was used to process and grid the data. This data series describes the methodology used and the resulting data projects.

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. The bathymetry will provide elevations and show geomorphic characteristics of the seafloor, while the backscatter and acoustical backscatter imagery will enhance the geomorphic characteristics and give insight to variations of sediment types on the seafloor. This file is the 50-m cell size grid of the combined swath and single-beam bathymetry around Cat Island, Miss.

During the summers of 2008 and 2009 the United States Geological Survey (USGS) conducted bathymetric surveys from West Ship Island, Mississippi, to Dauphin Island, Alabama, as part of the Northern Gulf of Mexico (NGOM) Ecosystem Change and Hazard Susceptibility project. The survey area extended from the shoreline out to approximately two kilometers and included the adjacent passes. These findings were originally published in Dewitt and others (2012). This USGS data release includes updated elevation point data (xyz) in which NOAA's Vdatum version 3.6 was used convert the 2008-2009 XYZ soundings to Universal Transverse Mercator (UTM) North American Datum of 1983 (NAD83) horizontal datum and North American Vertical Datum of 1988 (NAVD88) GEOID12B vertical datum. One goal of this work was to create time-series of bathymetric change maps around the islands using data collected between 1916 to 1920, 2008 to 2009, and in 2016.

In August of 2013, the U.S. Geological Survey (USGS) conducted geophysical surveys offshore of Petit Bois Island, Mississippi. These efforts are a continued part of the U.S. Geological Survey Gulf of Mexico Science Coordination partnership with the U.S. Army Corps of Engineers (USACE) to assist the Mississippi Coastal Improvements Program (MsCIP) and the Northern Gulf of Mexico (NGOM) Ecosystem Change and Hazards Susceptibility Project, by mapping the shallow geologic stratigraphic framework of the Mississippi Barrier Island Complex. These geophysical surveys will provide the data necessary for scientists to define, interpret, and provide baseline bathymetry and seafloor habitat for this area to aid scientists in predicting future geomorphological changes to the islands with respect to climate change, storm impacts, and sea level rise. Furthermore, these data combined with the geomorphological results will provide the properties and extent of local offshore sand sediment resources available for planning and execution of the Gulf Islands National Seashore barrier island restoration. The geophysical data were collected during one cruise (USGS Field Activity Numbers 13CCT04) aboard the University of Southern Mississippi Research Vessel Tommy Munro offshore along the gulf side of Petit Bois Island, Gulf Islands National Seashore, Mississippi. Data were acquired with the following equipment: a Systems Engineering and Assessment, Ltd., SWATHplus interferometric sonar (468 kilohertz (kHz)), an EdgeTech 424 (4-24 kHz), an EdgeTech 525i chirp sub-bottom profiling system, and a Klein 3900 sidescan sonar system. This report serves as an archive of the processed interferometric swath bathymetry and sidescan sonar data. Geographic information system data products include an interpolated digital elevation model, an acoustic backscatter mosaic, a trackline map, and point data files. Additional files include error analysis maps, Field Activity Collection System logs, and formal Federal Geographic Data Committee metadata. NOTE: These data are scientific in nature and are not to be used for navigation. Any use of trade names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

These metadata describe the U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center (PCMSC) 2010 bathymetry data collected in Skagit Bay Washington that is provided as a 1-m resolution TIFF image, as well as a 1-m resolution shaded-relief TIFF image. In 2004, 2005, 2007, and 2010 the U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center (PCMSC) collected bathymetry and acoustic backscatter data in Skagit Bay, Washington using an interferometric bathymetric sidescan sonar system mounded to the USGS R/V Parke Snavely and the USGS R/V Karluk. The research was conducted in coordination with the Swinomish Indian Tribal Community, Skagit River System Cooperative, Skagit Watershed Council, Puget Sound Nearshore Ecosystem Restoration Project, and U.S. Army Corps of Engineers to characterize estuarine habitats and processes, including the sediment budget of the Skagit River and the influence of river-delta channelization on sediment transport. Information quantifying the distribution of habitats and extent that sediment transport influences habitats and the morphology of the delta is useful for planning for salmon recovery, agricultural resilience, flood risk protection, and coastal change associated with sea-level rise.

In 2010, the U.S. Geological Survey in Woods Hole, MA and St. Petersburg, FL, in partnership with the U.S. Army Corps of Engineers, Mobile District conducted geologic mapping to characterize the seafloor and shallow subsurface stratigraphy offshore of the Gulf Islands of Mississippi. The mapping was carried out during two cruises in March, 2010 on the R/V Tommy Munro of Biloxi, MS. Data were acquired with the following equipment: an SEA Ltd SwathPlus interferometric sonar (both 234 kHz and 468 kHz systems), a Klein 3000 and a Klein 3900 dual frequency sidescan-sonar, and an Edgetech 512i chirp subbottom profiling system. The long-term goal of this mapping effort is to produce high-quality, high-resolution geologic maps and geophysical interpretations that can be utilized to identify sand resources within the region and better understand the Holocene evolution and anticipate future changes in this coastal system. More information on the field work can be accessed from the Woods Hole Coastal and Marine Science Center Field Activity webpage https://cmgds.marine.usgs.gov/fan_info.php?fan=2010-012-FA or the St. Petersburg Coastal and Marine Geology InfoBank https://walrus.wr.usgs.gov/infobank/m/m210gm/html/m-2-10-gm.meta.html.

These metadata describe the U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center (PCMSC) 2007 bathymetry data collected in Skagit Bay Washington that is provided as a 1-m resolution TIFF image, as well as a 1-m resolution shaded-relief TIFF image. In 2004, 2005, 2007, and 2010 the U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center (PCMSC) collected bathymetry and acoustic backscatter data in Skagit Bay, Washington using an interferometric bathymetric sidescan sonar system mounded to the USGS R/V Parke Snavely and the USGS R/V Karluk. The research was conducted in coordination with the Swinomish Indian Tribal Community, Skagit River System Cooperative, Skagit Watershed Council, Puget Sound Nearshore Ecosystem Restoration Project, and U.S. Army Corps of Engineers to characterize estuarine habitats and processes, including the sediment budget of the Skagit River and the influence of river-delta channelization on sediment transport. Information quantifying the distribution of habitats and extent that sediment transport influences habitats and the morphology of the delta is useful for planning for salmon recovery, agricultural resilience, flood risk protection, and coastal change associated with sea-level rise.