Metadata: Identification_Information: Citation: Citation_Information: Originator: U.S. Geological Survey Publication_Date: 20161221 Title: Coastal Interferometric Swath Bathymetry Data Collected in 2015 from the Chandeleur Islands, Louisiana: 2015_Chand_IFB_5m_NAD83_NAVD88_GEOID09_DEM Geospatial_Data_Presentation_Form: Raster digital data Series_Information: Series_Name: U.S. Geological Survey Data Release Issue_Identification: doi:10.5066/F7NV9GC8 Online_Linkage: https://doi.org/10.5066/F7NV9GC8 Description: Abstract: The U.S. Geological Survey St. Petersburg Coastal and Marine Science Center (USGS SPCMSC), collected swath bathymetry data offshore of the Northern Chandeleur Islands, Louisiana in September 2015. This USGS Data Release includes the resulting processed elevation point data (xyz) and an interpolated digital elevation model (DEM). For further information regarding data collection and/or processing methods, refer to previously published USGS Data Series 847 and 848 (https://doi.org/10.3133/ds8487 and https://doi.org10.3133/ds848) Purpose: This zip archive contains a DEM that was derived from processed x,y,z data points for the interferometric swath bathymetry data collected in September 2015 offshore of the Chandeleur Islands, Louisiana (USGS field activity number (FAN), 2015-331-FA). Additional survey and data details are available at http://cmgds.marine.usgs.gov/fan_info.php?fan=2015-331-FA Supplemental_Information: The DEM was derived from processed swath data that are provided as an American Standard Code for Information Interchange (ASCII) x,y,z point data file. These values are not the individual soundings but are the exported BASE (Bathymetry with Associated Statistical Error) surface at 5-meter spatial distances with associated CUBE (Combined Uncertainty and Bathymetry Estimator) sample surface created from the edited soundings dataset using CARIS HIPS and SIPS version 9.1. These are considered interpolated samples in which one value represents all soundings within a five-meter node, weighted by uncertainty and proximity, giving the final value as a data sample within the specific grid cell. The swath bathymetry data were collected and processed in World Geodetic System of 1984 (WGS84). This dataset was subsequently transformed to the North American Datum of 1983 (NAD83), using the National Oceanic and Atmospheric Administration (NOAA) VDatum version 3.5 transformation software (http://vdatum.noaa.gov/), and included in the data release as 2015_Chand_IFB_5m_NAD83_NAVD88_GEOID09_XYZ.txt. The data were collected using the WGS 84 reference ellipsoid. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20150915 Ending_Date: 20150921 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: Not planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -88.87805384 East_Bounding_Coordinate: -88.83262031 North_Bounding_Coordinate: 30.07266169 South_Bounding_Coordinate: 30.01512066 Keywords: Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:d9526068-88bd-48b1-b76b-fe14fa4f9260 Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: oceans Theme_Keyword: elevation Theme_Keyword: location Theme_Keyword: geoscientificInformation Theme_Keyword: imageryBaseMapsEarthCover Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: marine geology Theme_Keyword: geophysics Theme_Keyword: bathymetry Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: interferometry Theme_Keyword: swath Theme_Keyword: Systems Engineering and Assessment Theme_Keyword: SEA Theme_Keyword: SWATHplus-H Theme_Keyword: hydrography Theme_Keyword: geophysical Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Theme_Keyword: Coastal and Marine Geology Program Theme_Keyword: CMGP Theme_Keyword: St. Petersburg Coastal and Marine Science Center Theme_Keyword: SPCMSC Theme_Keyword: Barrier Island Evolution Research Project Theme_Keyword: Barrier Island Mapping Theme_Keyword: 2015-331-FA Theme_Keyword: datum Theme_Keyword: shoreline Theme_Keyword: interferometric bathymetry Theme_Keyword: IFB Place: Place_Keyword_Thesaurus: Geographic Names Information System (GNIS) Place_Keyword: Louisiana Place_Keyword: Gulf of Mexico Place_Keyword: Chandeleur Islands Stratum: Stratum_Keyword_Thesaurus: Oregon Geospatial Enterprise Office (GEO) Stratum Keyword Stratum_Keyword: sea surface Stratum_Keyword: epipelagic Temporal: Temporal_Keyword_Thesaurus: None Temporal_Keyword: September 2015 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 to be acknowledged as originator of these data in future products or derivative research. Access_Constraints: none Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Jake J. Fredericks Contact_Organization: U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center 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)502-8033 Contact_Electronic_Mail_Address: jfredericks@usgs.gov Data_Set_Credit: U.S. Geological Survey, Coastal and Marine Geology Program, St. Petersburg Coastal and Marine Science Center Native_Data_Set_Environment: Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; Esri ArcGIS 10.2.2.3552 Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The accuracy of the data was determined during data collection. This dataset was from one research cruise and was therefore internally consistent. Methods were employed to maintain data collection consistency aboard the platform. During mobilization, each piece of equipment was isolated to obtain internal and external offset measurements with respect to the survey platform. All the critical measurements were recorded manually and digitally entered into their respective programs. For the interferometric swath bathymetry (IFB), offsets between the sonar head and the Differential Global Positioning System (DGPS) antennas were measured and entered into the CodaOctopus F190R+ internal setup program. The DGPS correction was obtained from Marinestar High-precision (HP) differential global navigation satellite system, a satellite positioning service, from Fugro, Inc. This signal was received through the Coda Octopus F190R+ GPS antennas. These bathymetric data have not been independently verified for accuracy. Logical_Consistency_Report: This file represents the post-processed bathymetric data (x,y,z) collected during a swath bathymetry survey (2015-331-FA). Completeness_Report: These are complete post-processed x,y,z bathymetric data points from acoustic swath data collected near the Chandeleur Islands, Louisiana, in September 2015. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Navigation information was recorded in real-time kinematic mode via the CODA Octopus F190R+ Precision Attitude and Positioning System. Differential GPS correction was obtained through the Marinestar HP broadcast subscription from Fugro, Inc. The manufacturer's stated horizontal accuracy is 10 centimeters (cm) 95% of the time. The trackline position data were recorded using HYPACK version 15.0.1.1 hydrographic acquisition and processing software. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: The manufacturer's stated vertical accuracy of Marinestar GPS subscription is 15 cm, 95% of the time. The Coda Octopus F190R+ inertial measurement unit (IMU), which integrates the Marinestar position with motion, measures vessel velocity (+/- 0.014 meters/second [m/s]), roll and pitch (less than 0.025 degrees), heading (1 m baseline 0.1 degrees), and heave (5 cm per meter (m) of depth). The vertical accuracy for the SWATHplus-H system varies with depth and across track range. At 57 m, it is accurate to 10 cm vertically. Maximum vertical transformation error reported by VDatum version 3.5 was 0.171 m or 17.1 centimeters for eastern Louisiana. The sum of the errors (+/- 0.013 m + +/-0.15 m +0.171 m) in the vertical direction is equal to +/-.334 m or +/- 33.4 cm. Lineage: Process_Step: Process_Description: Swath Bathymetry Acquisition: The interferometric swath bathymetry data were collected aboard the R/V Sallenger in September 2015 using the SEA SWATHplus-H 468 kHz interferometric sonar system. The transducer system was fastened to a static pole mount deployed over the starboard side gunnel. The Novatel GPS antennas were mounted atop the cabin. Boat position and motion data were recorded in real-time using a CodaOctopus F190R+ wetpod IMU. The IMU was mounted underwater between the transducer heads to minimize lever arm geometry errors between observed depths and vessel motion. Real-time corrected positions were acquired via Marinestar HP DGPS subscription service from Fugro, Inc. Marinestar HP position correction data and motion data from the IMU were integrated with interferometric soundings using SWATHplus software, version 3.10.2.0, with positional and calibration offsets pre-defined by a session file (.sxs), allowing for real-time-corrected depths. Before deployment, all equipment offsets were measured. During the survey, all swath tracklines were recorded in SWATHplus raw data format (.sxr). A Valeport Mini Sound Velocity Sensor (miniSVS) was attached to the transducer mount and collected continuous speed of sound (SOS) measurements at the depth of the transducers. These values were directly read and incorporated into the SWATHplus raw data format during acquisition providing a real-time speed of sound at the transducer while underway. In addition, a separate Mini Sound Velocity Profiler (Valeport miniSVP) was used to collect speed of sound profiles (water surface to seafloor) approximately every two hours throughout the survey as well as other areas of question such as rapid transitions in water depth. Process_Date: 2015 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Jake J. Fredericks Contact_Organization: U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: (727) 502-8033 Contact_Electronic_Mail_Address: jfredericks@usgs.gov Process_Step: Process_Description: Swath Bathymetry Processing: Data were collected with SWATHplus-H and Bathyswath 3.10.2, an acquisition and initial processing program. Preliminary roll calibration trackline data were collected and processed using Bathyswath Swath Processor version 3.10.2.0 and Bathyswath Grid Processor software version 3.10.0.0. Instrument offsets and calibration values were input into the session file (.sxs) and the raw data files (.sxr) were then processed using the updated system configuration file containing roll calibration values, measured equipment offsets, acquisition parameters, navigation and motion from the F190R+, SOS at the sonar head, and SVP cast data. Any calibration offsets and acoustic filtering utilized in Bathyswath was then applied to each raw data file to create a processed data file (.sxp), and then imported into advanced sounding data processing software CARIS HIPS and SIPS (CARIS) version 9.1. The initial real-time processing datum for the swath and backscatter data was WGS84, which is the acquisition datum for Marinestar HP position and navigation data. Within CARIS, outliers for the navigation data and processed soundings were removed using program filters. Any remaining data outliers were then removed manually. A CARIS BASE surface with associated CUBE sample surface was created from the edited soundings. A CUBE hypothesis is the estimated value of a grid node representing all the soundings within a chosen resolution or grid-cell size (for example, 5 m) weighted by uncertainty and proximity, giving the final value as a "sample" of the data within the specific grid cell. This algorithm allows for multiple grid-node hypotheses to be verified or overridden by the user while maximizing processing efficiency. A final visual inspection of the dataset in addition to Quality Control and Quality Assurance (QA/QC) procedures were implemented to ensure all outliers and erroneous data points had been removed from the final BASE surface. In order to provide the dataset in a non-proprietary format, the final XYZ data were exported as an ASCII comma-separated file. Process_Date: 20160416 Source_Produced_Citation_Abbreviation: 2015_Chand_IFB_5m_WGS84_XYZ.txt Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Jake J. Fredericks Contact_Organization: U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: (727) 502-8033 Contact_Electronic_Mail_Address: jfredericks@usgs.gov Process_Step: Process_Description: Datum Transformation: The text file 2015_Chand_IFB_5m_NAD83_NAVD88_GEOID09.txt was converted using VDatum version 3.5 from WGS84 to the North American Datum of 1983 (NAD83) reference frame and the North American Vertical Datum of 1988 (NAVD88) orthometric height using the National Geodetic Survey (NGS) geoid model of 2009 (GEOID09). Source_Used_Citation_Abbreviation: 2015_Chand_IFB_5m_WGS84_XYZ.txt Process_Date: 2016 Source_Produced_Citation_Abbreviation: 2015_Chand_IFB_5m_NAD83_NAVD88_GEOID09_XYZ.txt Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Noreen A. Buster Contact_Organization: U.S. Geological Survey St. Petersburg Coastal and Marine Science Center Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: (727) 502-8114 Contact_Electronic_Mail_Address: nbuster@usgs.gov Process_Step: Process_Description: DEM Creation: Final X,Y,Z point data were imported into Esri ArcGIS 10.2.2.3552 and gridded using the 3D Analyst and Spatial Analyst toolsets. A triangulated irregular network (TIN) was generated and then used to create the DEM by use of the "Tin to Raster" tool, natural neighbors algorithm, with a cell size of 25m. Elevation DEM raster created with a 25-m resolution. Source_Used_Citation_Abbreviation: 2015_Chand_IFB_5m_NAD83_NAVD88_GEOID09_XYZ.txt Process_Date: 20160512 Source_Produced_Citation_Abbreviation: 2015_Chand_IFB_25m_NAD83_NAVD88_GEOID09_DEM.tif Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Noreen A. Buster Contact_Organization: U.S. Geological Survey St. Petersburg Coastal and Marine Science Center Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: (727) 502-8114 Contact_Electronic_Mail_Address: nbuster@usgs.gov Process_Step: Process_Description: Added keywords section with USGS persistent identifier as theme keyword. Process_Date: 20201013 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: VeeAnn A. Cross Contact_Position: Marine Geologist Contact_Address: Address_Type: Mailing and Physical Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Contact_Voice_Telephone: 508-548-8700 x2251 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: vatnipp@usgs.gov Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: raster Raster_Object_Information: Raster_Object_Type: pixel Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 16 Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.999600 Longitude_of_Central_Meridian: -87.000000 Latitude_of_Projection_Origin: 0.000000 False_Easting: 500000.000000 False_Northing: 0.000000 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: row and column Coordinate_Representation: Abscissa_Resolution: 25.000000 Ordinate_Resolution: 25.000000 Planar_Distance_Units: meters Geodetic_Model: Horizontal_Datum_Name: North American Datum 1983 Ellipsoid_Name: Geodetic Reference System 80 Semi-major_Axis: 6378137.000000 Denominator_of_Flattening_Ratio: 298.257222101 Vertical_Coordinate_System_Definition: Altitude_System_Definition: Altitude_Datum_Name: North American Vertical Datum 1988 (GEOID09) Altitude_Resolution: 0.0001 cm Altitude_Distance_Units: meters Altitude_Encoding_Method: Attribute values Distribution_Information: Distributor: Contact_Information: Contact_Person_Primary: Contact_Person: Jake J. Fredericks Contact_Organization: U.S. Geological Survey - St. Petersburg Coastal and Marine Science Center 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)502-8033 Contact_Electronic_Mail_Address: jfredericks@usgs.gov Distribution_Liability: 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 constitute any such warranty. The USGS shall not be held liable for improper or incorrect use of the data described 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. Standard_Order_Process: Digital_Form: Digital_Transfer_Information: Format_Name: GeoTIFF Format_Version_Number: 2 Format_Specification: GeoTIFF Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://coastal.er.usgs.gov/data-release/doi-F7NV9GC8/data/2015_Chand_IFB_25m_NAD83_NAVD88_GEOID09_DEM.zip Fees: None Metadata_Reference_Information: Metadata_Date: 20201013 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Jake J. Fredericks Contact_Organization: U.S. Geological Survey St. Petersburg Coastal and Marine Science Center 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: jfredericks@usgs.gov Metadata_Standard_Name: Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Security_Information: Metadata_Security_Classification_System: none Metadata_Security_Classification: unclassified Metadata_Security_Handling_Description: None