50-Meter Digital Elevation Model of Coastal Bathymetry Collected during USGS Cruise 13CCT04 Offshore of Petit Bois Island, Gulf Islands National Seashore, Mississippi, August 2014

Metadata:


Identification_Information:
Citation:
Citation_Information:
Originator: U.S. Geological Survey
Publication_Date: 2014
Title:
50-Meter Digital Elevation Model of Coastal Bathymetry Collected during USGS Cruise 13CCT04 Offshore of Petit Bois Island, Gulf Islands National Seashore, Mississippi, August 2014
Geospatial_Data_Presentation_Form: raster digital data
Online_Linkage: http://pubs.usgs.gov/ds/###/data/raster/13CCT04
Larger_Work_Citation:
Citation_Information:
Originator: Nancy T. DeWitt
Originator: James G. Flocks
Originator: Jack L. Kindinger
Originator: Julie C. Bernier
Originator: Kyle W. Kelso
Originator: Dana S. Wiese
Originator: Dave P. Finlayson
Originator: William R. Pfeiffer
Publication_Date: 2014
Title:
Archive of Side Scan Sonar and Swath Bathymetry Data Collected During USGS Cruise 13CCT04 Offshore of Petit Bois Island, Gulf Islands National Seashore, Mississippi, August 2014
Geospatial_Data_Presentation_Form: multimedia presentation
Series_Information:
Series_Name: U.S. Geological Survey Data Series
Issue_Identification: ###
Publication_Information:
Publication_Place: St. Petersburg, FL
Publisher: U.S. Geological Survey
Online_Linkage: http://pubs.usgs.gov/ds/###
Description:
Abstract:
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.
Purpose:
This 50 meter cell size digital elevation model is an interpretive product that was derived from the processed interferometric swath bathymetry data collected in August 2013 offshore of Petit Bois Island, Gulf Islands National Seashore, Mississippi.
Supplemental_Information:
The interferometric swath bathymetry was acquired using OmniSTAR High Precision Differential Geographic Positioning System (DGPS) in the ITRF2005 datum. However at various times during the cruise, difficulty in acquiring and maintaining satellite signal lock was encountered; therefor compromising the DGPS signal. To resolve the questionable DGPS accuracy for the vertical component a NOAA Tide Zone model was applied with verified six minute tide data from the Pascagoula NOAA Lab tide station (#8741533) and the Bay Waveland Yacht Club tide station (#8747437). The referenced the vertical (z) component was to Mean Low Lower Water (MLLW) datum. The dataset was transformed horizontally to WGS84(G1150)and also to NAD83 using GEOID12A (NOAA NGS VDatum software version 3.2 - http://vdatum.noaa.gov/). The final x,y,z position data was gridded at a 50 meter cell size resolution to create the digital elevation model.
Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20130813
Ending_Date: 20130823
Currentness_Reference: ground condition
Status:
Progress: Complete
Maintenance_and_Update_Frequency: none
Spatial_Domain:
Bounding_Coordinates:
West_Bounding_Coordinate: -88.542109
East_Bounding_Coordinate: -88.320794
North_Bounding_Coordinate: 30.193342
South_Bounding_Coordinate: 30.076200
Keywords:
Theme:
Theme_Keyword_Thesaurus: ISO 19115 Topic Category
Theme_Keyword: elevation
Theme_Keyword: geoscientificInformation
Theme_Keyword: imageryBaseMapsEarthCover
Theme_Keyword: oceans
Theme:
Theme_Keyword_Thesaurus: General
Theme_Keyword: marine geology
Theme_Keyword: bathymetry
Theme_Keyword: interferometry
Theme_Keyword: swath
Theme_Keyword: CARIS
Theme_Keyword: HIPS and SIPS
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: Coastal Change and Transport
Theme_Keyword: Interferometric Bathymetry
Theme_Keyword: 13CCT04
Theme_Keyword: Digital Elevation Model
Place:
Place_Keyword_Thesaurus: Geographic Names Information System (GNIS)
Place_Keyword: Gulf Islands National Seashore
Place_Keyword: Gulf of Mexico
Place_Keyword: Mississippi Sound
Place_Keyword: Petit Bois Island
Access_Constraints: None
Use_Constraints:
The U.S. Geological Survey requests that it be referenced as the originator of this dataset in any future products or research derived from these data. These data should not be used for navigational purposes.
Point_of_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: Nancy T. DeWitt
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: ndewitt@usgs.gov
Data_Set_Credit:
U.S. Geological Survey, Coastal and Marine Geology Program, St. Petersburg Coastal and Marine Science Center (SPCMSC)
Native_Data_Set_Environment:
Microsoft Windows 7 Service Pack 1; ESRI ArcGIS 10.1 Service Pack 1 Build 3143; Esri ArcCatalog 10.1 Build 3143

Data_Quality_Information:
Attribute_Accuracy:
Attribute_Accuracy_Report:
The accuracy of the data is determined during data collection. Methods are employed to maintain data collection consistency aboard various platforms. During mobilization, each piece of equipment 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 is complete and calibration status is considered acceptable, then survey operations commence. The system has a dedicated computer, and efforts are made to utilize the same equipment and software versions on both systems. However, upgrades and changes occur and require additional setup, measurements, and notation. For the interferometric swath bathymetry, offsets between the sonar head and the DGPS antennas were measured and entered into the CodaOctopus F190R internal setup program. DGPS was provided through the OmniSTAR High Performance wide-area GPS service. DGPS is always implemented for navigational accuracy either during acquisition or as a post-processing step. These bathymetric data have not been independently verified for accuracy.
Logical_Consistency_Report:
The interferometric swath bathymetry data were collected during one research cruise in August, 2013. Refer to the online data series linkage for field logs, vessel platform descriptions, and other survey information. This dataset was created to provide a post-processed bathymetric grid from the data. The digital elevation model is 50 meter cell-size resolution; data gaps between acquisition tracklines are predicted values generated by the gridding algorithm.
Completeness_Report:
This is a completely processed digital elevation model representing an interpolated bathymetric surface derived from the acoustic interferometric swath bathymetry data.
Positional_Accuracy:
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
The stated horizontal accuracy of the OmniSTAR HP navigation subscription used during swath bathymetry acquisition is reported by the service as +/-15 cm (95% of the time).
Quantitative_Horizontal_Positional_Accuracy_Assessment:
Horizontal_Positional_Accuracy_Value: -0.00000134 to +0.00000134
Horizontal_Positional_Accuracy_Explanation: latitude decimal degrees
Quantitative_Horizontal_Positional_Accuracy_Assessment:
Horizontal_Positional_Accuracy_Value: -0.0000019 to +0.0000019
Horizontal_Positional_Accuracy_Explanation: longitude decimal degrees
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
The stated vertical accuracy of the OmniSTAR HP navigation subscription used during swath bathymetry acquisition is +/-0.15 m (95% of the time). The Coda Octopus F190R IMU, which integrates the OmniSTAR HP position with motion, measures vessel velocity (+/- 0.014 m/s), roll and pitch (< 0.025 degrees), heading (1 m baseline 0.1 degrees), and heave (5 cm per meter of depth). The vertical accuracy for the SWATHplus-H system varies with depth and across track range. Insert tide model error here
Lineage:
Process_Step:
Process_Description:
Swath Bathymetry Acquisition: The interferometric swath bathymetry data were collected aboard the R/V Tommy Munro using the SEA SWATHplus-H 468 kHz interferometric sonar system. The system was fastened to a static pole mount with the sonar transducer in line with the Novatel GPS antennas sitting atop the mount. Boat position and motion data were recorded in real-time using a CodaOctopus F190R wetpod inertial measurement unit (IMU) mounted underwater between the transducer heads to minimize lever arm geometry errors between the observed depths and associated vessel motion. Real-time corrected positions were acquired via OmniSTAR HP (High-Precision differential global navigation satellite system) differential subscription service. OmniSTAR HP position correction data and motion data from the IMU were integrated with interferometric soundings in the SWATHplus software version 3.7.17 with positional and calibration offsets pre-defined by a session file(.sxs), allowing for real-time-corrected depths. Prior to deployment, all equipment offsets were measured. During the survey all swath tracklines were recorded in SEA SWATHplus raw data format (.sxr). A Valeport Mini Sound Velocity Sensor (SVS) was attached to the transducer mount and collected continuous 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 sound velocity profiler (Valeport miniSVP) was used to collect speed of sound profiles (water surface to seafloor) at intervals throughout the survey.
Process_Date: 2014
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: Nancy T. DeWitt
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: ndewitt@usgs.gov
Process_Step:
Process_Description:
Swath Bathymetry Processing: The Systems Engineering and Assessment Ltd., program SWATHplus serves as acquisition software and initial processing software. Preliminary roll calibration data were collected and processed using SWATHplus and Grid Processor software versions 3.07.17. Instrument offset and calibration values were then input into the session file (.sxs). The raw data files (.sxr) were processed using the updated system configuration file that contained the roll calibration values, measured equipment offsets, acquisition parameters, navigation parameters, SOS at sonar head, and the SVP cast data. Any acoustic filtering applied in SWATHplus was also written to the processed data file (.sxp). The initial datum for the swath and backscatter data was ITRF05, which is the real-time acquisition datum of OmniSTAR HP position and navigation data.
All processed data files (.sxp) were imported into CARIS HIPS and SIPS version 8.1 and finalized in version 8.1.7. The tide zone model and associated verified six minute tide data were applied using the CARIS Load Tide tool. The total propogated uncertainty was calculated. The original sounding data were edited for outliers using the CARIS Swath Editor tool and associated depth filters. Remaining outliers were then deleted manually. A CARIS BASE (Bathymetry with Associated Statistical Error) surface with the associated CUBE (Combined Uncertainty and Bathymetry Estimator) sample surface was created from the edited soundings dataset. A BASE hypothesis is the estimated value of a grid node representing all the soundings within a chosen resolution or grid-cell size (for example, 2 m) weighted by uncertainty and proximity, giving the final value as a "sample" of the data within the specific grid cell. A 2-m resolution CUBE surface was created to perform initial CUBE hypothesis editing followed by a higher 1-m resolution BASE surface cleaning using the CARIS Subset Editor tool. The 2-m resolution BASE surface sample x,y,z data were exported as ASCII in the ellipsoid datum of ITRF05 and MLLW vertical datum. The data were then transformed horizontally into WGS84(G1150) and also NAD83 referenced to GEOID12A with NOAA's VDatum software conversion tool version 3.2.
Process_Date: 2013
Source_Produced_Citation_Abbreviation: 13CCT04_v2_IFB_04_2m_ITRF05_MLLW.txt
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: Nancy DeWitt
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: ndewitt@usgs.gov
Process_Step:
Process_Description:
Datum transformation: Using the transformation software VDatum version 3.2, the interferometric swath bathymetric data were transformed horizontally from their data acquisition datum (ITRF05) to the WGS84 (G1150) and North American Datum of 1983 (NAD83) reference frame using the National Geodetic Survey (NGS) geoid model of 2012A (GEOID12A).
Source_Used_Citation_Abbreviation:
13CCT04_v2_IFB_04_2m_ITRF05_MLLW_XY_part1of6; 13CCT04_v2_IFB_04_2m_ITRF05_MLLW_XY_part2of6; 13CCT04_v2_IFB_04_2m_ITRF05_MLLW_XY_part3of6; 13CCT04_v2_IFB_04_2m_ITRF05_MLLW_XY_part4of6; 13CCT04_v2_IFB_04_2m_ITRF05_MLLW_XY_part5of6; 13CCT04_v2_IFB_04_2m_ITRF05_MLLW_XY_part6of6
Process_Date: 2014
Source_Produced_Citation_Abbreviation:
13CCT04_v2_IFB_04_2m_WGS84_G1150_MLLW_part1of6; 13CCT04_v2_IFB_04_2m_WGS84_G1150_MLLW_part2of6; 13CCT04_v2_IFB_04_2m_WGS84_G1150_MLLW_part3of6; 13CCT04_v2_IFB_04_2m_WGS84_G1150_MLLW_part4of6; 13CCT04_v2_IFB_04_2m_WGS84_G1150_MLLW_part5of6; 13CCT04_v2_IFB_04_2m_WGS84_G1150_MLLW_part6of6
Source_Produced_Citation_Abbreviation:
13CCT04_v2_IFB_04_2m_NAD83_MLLW_XY_part1of6; 13CCT04_v2_IFB_04_2m_NAD83_MLLW_XY_part2of6; 13CCT04_v2_IFB_04_2m_NAD83_MLLW_XY_part3of6; 13CCT04_v2_IFB_04_2m_NAD83_MLLW_XY_part4of6; 13CCT04_v2_IFB_04_2m_NAD83_MLLW_XY_part5of6; 13CCT04_v2_IFB_04_2m_NAD83_MLLW_XY_part6of6
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: Nancy DeWitt
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: ndewitt@usgs.gov
Process_Step:
Process_Description:
Gridding Bathymetric data: Using Esri ArcGIS, the swath soundings were imported into ESRI’s ArcMap version 10.1 and gridded using the Geostatistical Analyst Tool's "radial basis function". This allowed the user to adjust interpolation parameters with regard to real data spatial resolution and orientation when predicting values. This method provided for a less biased representation of the dataset as a whole. A cross-validation report can be generated when using the radial basis function that helps the user understand how well the model will predict data values at locations without data points. In general the cross-validation takes one point and predicts its position using the weighted surrounding data values. This predicted value is compared against the actual value of that data point and general statistics are computed. The validation report for the swath bathymetry 50-m grid is listed below. The radial basis function surface was exproted to a raster file. A bounding polygon representing the extent of survey tracklines was created and converted into a raster mask using the ArcGIS "polygon to raster" conversion tool. The DEM was then clipped to the raster mask using the ArcGIS Spatial Analyst "extract by raster mask" tool. It is common, in large-area, shallow water surveys, to find wide data gaps between tracklines relative to the swath width surveyed. To minimize this concern in the final DEM, the ArcGIS Spatial Analyst "neighborhood" low-pass raster- data filter was applied.
Source_Used_Citation_Abbreviation:
13CCT04_v2_IFB_04_2m_WGS84(G1150)_MLLW_txt: This text file is the combination of files 13CCT04_v2_IFB_04_2m_WGS84(G1150)_MLLW_partXof6.txt (Where X is 1 through 6).
Process_Date: 2014
Source_Produced_Citation_Abbreviation: 13CCT04_IFB_04_WGS84_G1150_MLLW_DEM.tif
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: Nancy DeWitt
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: ndewitt@usgs.gov

Spatial_Data_Organization_Information:
Direct_Spatial_Reference_Method: Raster
Raster_Object_Information:
Raster_Object_Type: Grid Cell
Row_Count: 257
Column_Count: 427
Vertical_Count: 1

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: 0.9996
Longitude_of_Central_Meridian: -87.0
Latitude_of_Projection_Origin: 0.0
False_Easting: 500000.0
False_Northing: 0.0
Planar_Coordinate_Information:
Planar_Coordinate_Encoding_Method: row and column
Coordinate_Representation:
Abscissa_Resolution: 50
Ordinate_Resolution: 50
Planar_Distance_Units: meter
Geodetic_Model:
Horizontal_Datum_Name: D North American 1983
Ellipsoid_Name: GRS 1980
Semi-major_Axis: 6378137.0
Denominator_of_Flattening_Ratio: 298.257222101
Vertical_Coordinate_System_Definition:
Depth_System_Definition:
Depth_Datum_Name: Mean Lower Low Water (MLLW)
Depth_Resolution: 0.10
Depth_Distance_Units: meter
Depth_Encoding_Method: Implicit coordinate

Distribution_Information:
Distributor:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: Nancy DeWitt
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: ndewitt@usgs.gov
Resource_Description: Downloadable data
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, 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: GeoTIFF
File_Decompression_Technique: ZIP
Transfer_Size: 352 KB
Digital_Transfer_Option:
Online_Option:
Computer_Contact_Information:
Network_Address:
Network_Resource_Name:
http://pubs.usgs.gov/ds/###/data/raster/13CCT04_IFB_50_ITRF05_MLLW_DEM.zip
Offline_Option:
Offline_Media: DVD
Recording_Capacity:
Recording_Density: 4.75
Recording_Density_Units: GB
Recording_Format: UDF
Fees: none
Technical_Prerequisites:
The raster contained in the .zip file is available as GeoTIFF. To utilize this data, the user must have a GIS software package capable of reading .tif format.

Metadata_Reference_Information:
Metadata_Date: 2014
Metadata_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: Nancy T. DeWitt
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: ndewitt@usgs.gov
Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata
Metadata_Standard_Version: FGDC-STD-001-1998
Metadata_Use_Constraints:
The U.S. Geological Survey requests that it be referenced as the originator of this dataset in any future products or research derived from these data.
Metadata_Security_Information:
Metadata_Security_Classification_System: None
Metadata_Security_Classification: Unclassified
Metadata_Security_Handling_Description: None

Generated by mp version 2.9.27 on Thu Sep 18 09:11:50 2014