Identification_Information: Citation: Citation_Information: Originator: U.S. Geological Survey Publication_Date: 2011 Title: tmunro_50m.asc - swath bathymetry collected by the U.S. Geological Survey offshore of the Gulf Islands, MS, 2010 (ESRI ASCII GRID) Edition: 1.0 Geospatial_Data_Presentation_Form: raster digital data Series_Information: Series_Name: Open-File Report Issue_Identification: 2010-1178 Publication_Information: Publication_Place: Woods Hole Science Center, Woods Hole, MA Publisher: U.S. Geological Survey, Coastal and Marine Geology Program Online_Linkage: http://pubs.usgs.gov/of/2010/1178/GIS_catalog/Bathy/bathy_grd.zip Larger_Work_Citation: Citation_Information: Originator: Elizabeth A. Pendleton Originator: Wayne E. Baldwin Originator: William W. Danforth Originator: Nancy T. Dewitt Originator: David S. Foster Originator: Arnell S. Forde Originator: Kyle W. Kelso Originator: William R. Pfeiffer Originator: Aaron M. Turecek Originator: James G. Flocks Originator: David C. Twichell Publication_Date: 2011 Title: Geophysical Data from offshore of the Gulf Islands from West Ship Island to Dog Key Pass, Mississippi Edition: 1.0 Series_Information: Series_Name: Open-File Report Issue_Identification: 2010-1178 Publication_Information: Publication_Place: Woods Hole Science Center, Woods Hole, MA Publisher: U.S. Geological Survey, Coastal and Marine Geology Program Online_Linkage: http://pubs.usgs.gov/of/2010/1178/ Description: Abstract: This report contains the geophysical, geospatial, and geologic interpretive data that were collected during two cruises on the R/V Tommy Munro along the western, offshore side of the Gulf Islands of Mississippi in 2010. Geophysical data were collected by the U.S. Geological Survey in Woods Hole, MA and St. Petersburg, FL, in cooperation with the U.S. Army Corps of Engineers Mobile District. Bathymetric, sidescan-sonar, and chirp-seismic data were acquired with the following equipment, respectively: a Systems Engineering and Assessment, Ltd., SwathPlus interferometric sonar; Klein 3000 and 3900 dual-frequency sidescan sonars; and an EdgeTech 512i chirp sub-bottom profiling system. Processed geospatial data files of the geophysical data are provided here, and were generated to attain the long-term goal of this mapping effort, which 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. Purpose: This grid represents approximately 270 square km of bathymetric data that were collected in 2010. These data are used to define the sea-floor morphology offshore of the Gulf Islands in Mississippi. Time_Period_of_Content: Time_Period_Information: Multiple_Dates/Times: Single_Date/Time: Calendar_Date: 20100304 Single_Date/Time: Calendar_Date: 20100305 Single_Date/Time: Calendar_Date: 20100306 Single_Date/Time: Calendar_Date: 20100307 Single_Date/Time: Calendar_Date: 20100308 Single_Date/Time: Calendar_Date: 20100309 Single_Date/Time: Calendar_Date: 20100311 Single_Date/Time: Calendar_Date: 20100315 Single_Date/Time: Calendar_Date: 20100316 Single_Date/Time: Calendar_Date: 20100317 Single_Date/Time: Calendar_Date: 20100319 Single_Date/Time: Calendar_Date: 20100320 Single_Date/Time: Calendar_Date: 20100327 Single_Date/Time: Calendar_Date: 20100328 Single_Date/Time: Calendar_Date: 20100329 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -89.083910 East_Bounding_Coordinate: -88.635118 North_Bounding_Coordinate: 30.231222 South_Bounding_Coordinate: 30.125219 Keywords: Theme: Theme_Keyword_Thesaurus: General Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Theme_Keyword: Woods Hole Coastal and Marine Science Center Theme_Keyword: WHSC Theme_Keyword: Coastal and Marine Geology Program Theme_Keyword: CMGP Theme_Keyword: bathymetry Theme_Keyword: swath bathymetry Theme_Keyword: interferometry Theme_Keyword: sea-floor morphology Theme_Keyword: WHSC field activity serial number 2010-012 Theme_Keyword: ArcRaster grid Theme_Keyword: St. Petersburg Coastal and Marine Science Center Theme_Keyword: CCWS Theme_Keyword: R/V Tommy Munro Theme_Keyword: St. Petersburg field activity serial number 10cct02 Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: oceans Theme_Keyword: oceans and coastal Theme_Keyword: oceans and estuaries Theme_Keyword: elevation Theme_Keyword: geoscientificInformation Theme_Keyword: imageryBaseMapsEarthCover Place: Place_Keyword_Thesaurus: General Place_Keyword: Mississippi Place_Keyword: Gulf Islands Place_Keyword: North Central Gulf Coast Place_Keyword: United States Place_Keyword: West Ship Island Place_Keyword: East Ship Island Place_Keyword: Horn Island Place_Keyword: Dog Key Pass Place_Keyword: Camille Cut Place_Keyword: Petit Bois Island Place_Keyword: Gulfport Ship Channel Place_Keyword: Gulf of Mexico Access_Constraints: None Use_Constraints: The Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: David C. Twichell Contact_Organization: U.S. Geological Survey Contact_Position: Oceanographer Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Rd. City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Contact_Voice_Telephone: (508) 548-8700x2266 Contact_Facsimile_Telephone: (508) 457-2310 Contact_Electronic_Mail_Address: dtwichell@usgs.gov Browse_Graphic: Browse_Graphic_File_Name: http://pubs.usgs.gov/of/2010/1178/images/bathy_grd.png Browse_Graphic_File_Description: 50-m swath bathymetric grid offshore of the Gulf Islands, MS Browse_Graphic_File_Type: PNG Native_Data_Set_Environment: Microsoft Windows XP Professional x64 Edition Version 2003 Service Pack 2; ESRI ArcCatalog 9.3 Build 1770 Cross_Reference: Citation_Information: Originator: Lijuan Huang Publication_Date: 20100226 Title: NOAA/NOS Hydrographic Planning Team (HPT) tide zone model Online_Linkage: http://www.tidesandcurrents.noaa.gov/hydro.html Cross_Reference: Citation_Information: Originator: J. F. Luis Publication_Date: 2007 Title: Mirone: A multi-purpose tool for exploring grid data. Geospatial_Data_Presentation_Form: document Series_Information: Issue_Identification: 33 Publication_Information: Publisher: Computers and Geosciences Online_Linkage: http://w3.ualg.pt/~jluis/mirone/mirone_Refs.htm Cross_Reference: Citation_Information: Originator: P. Wessel Originator: W.H.F. Smith Publication_Date: 1998 Title: New, improved version of the Generic Mapping Tools released Geospatial_Data_Presentation_Form: document Series_Information: Series_Name: EOS Transactions Issue_Identification: 79 Publication_Information: Publisher: American Geophysical Union Online_Linkage: http://gmt.soest.hawaii.edu/ Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: All attributes were checked in a consistent manner. Logical_Consistency_Report: Any spurious data points were removed during processing. Completeness_Report: All shore parallel survey lines were incorporated. Tie (shore perpendicular) lines were not used in grid generation. The R/V Tommy Munro was contracted for the month of March 2010. The Woods Hole Science Center acquired data onboard between March 4 and March 17, 2010. Bathy data were acquired on 20100304-20100309; 20100311;20100315-20100317. Day gaps in acquisition were due to inclement weather or seismic tieline acquisition. The St. Petersburg Coastal and Marine Science Center acquired data onboard the R/V Tommy Munro between March 19 and March 29, 2010. Bathy data for this dataset were acquired on 201003019-20100320; 20100327-2010329. Day gaps in acquisition were due to inclement weather or data acquisition in another survey area. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: These data were navigated with a Differential Global Positioning System (DGPS); they are accurate to +/- 1 to 2 meters, horizontally. Unless noted, all DGPS data are referenced to WGS84, and distance between sidemounted interferometric sonar and GPS antennae are corrected. Quantitative_Horizontal_Positional_Accuracy_Assessment: Horizontal_Positional_Accuracy_Value: 2 meters Horizontal_Positional_Accuracy_Explanation: The differential GPS is accurate within 1 to 2 meters. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: The theoretical vertical resolution of the SEA Ltd SwathPlus interferometric sonar is 1 % of water depth, approximately 0.1 m within the study area. An Octopus F180 Attitude and Positioning system was used to correct for vessel roll, pitch, heave, and yaw during the first leg, 2010-012FA, whereas an Octopus F190 Attitude and Positioning system was used during the second leg, 10cct02. Tidal offsets were corrected with a NOAA tide zone model and referenced to mean lower low water (MLLW). Errors associated with the tidal zone model could be less than or equal to the tidal range for this area which is ~0.4 m. The gridding algorithm and cell size used on these data could introduce errors as great as 3 m along the edges of the Gulfport Ship Channel. Gridding-induced errors are likely much smaller (< 0.5 m) for most of the study area where slopes are less than 1 degree. Changes in ship draft due to water and fuel usage were not considered. Quantitative_Vertical_Positional_Accuracy_Assessment: Vertical_Positional_Accuracy_Value: 0.5 meters Vertical_Positional_Accuracy_Explanation: The vertical resolution of the interferometric system combined with the zone tidal model produces an error of half a meter. Errors associated with the gridding algorithm are not included here. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: U.S. Geological Survey Type_of_Source_Media: disc Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20100304 Ending_Date: 20100315 Source_Contribution: Swath data acquisition at sea (2010): These bathymetric data were collected with 2 SEA Ltd Swathplus interferometric sonars (a 234 kHz and a 468 kHz system) mounted on the portside of the R/V Tommy Munro of Biloxi, MS. The Woods Hole Science Center acquired data with the 234 kHz system between March 4, 2010 and March 17, 2010. The St. Petersburg Coastal and Marine Science Center acquired data with the 468 kHz system between March 19, 2010 and March 29, 2010. All data were acquired with SwathPlus Software (version: 3.6.5). Tracklines are spaced 150 m apart in the shore parallel direction. Process_Step: Process_Description: SwathPlus Software (version: 3.6.5) was used to acquire the raw swath data (*.sxr) and output a processed soundings file (*.sxp). Several bathy filters were applied to the processed file within SwathPlus to remove erroneous soundings and reduce the density of the data. Corrections were also applied for speed of sound changes (using sound velocity profiles), ship motion, GPS antennae offsets, and transducer depth and angle below the surface. Bathy filters included a low amplitude (100), range (1-m below the surface), box (2-m to avoid nadir), alongtrack 1 (depth difference of 10-m, window size 10-m, and learn rate of 0.6), alongtrack 2 (depth difference of 1-m, window size 1-m, and learn rate of 0.9), and a mean filter (0.1-m). Process_Date: 2010 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Elizabeth A. Pendleton Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Rd. City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Contact_Voice_Telephone: (508) 548-8700x2259 Contact_Facsimile_Telephone: (508) 457-2310 Contact_Electronic_Mail_Address: ependleton@usgs.gov Process_Step: Process_Description: CARIS (version: HIPS and SIPS 6.1; service pack 2) was used to import the processed bathy files (*.sxp) from SwathPlus format to CARIS HDCS data format using the conversion utility. The data were corrected for errors in soundings due to additional sound refraction not accounted for by sound velocity profiles using the CARIS refraction editor. These artifacts can be recognized in a cross-swath profile of a relatively flat patch of sea floor. When viewing the swath data across a profile, the sea floor will appear to have a "frown" or "smile" when in fact the data should be flat across the profile. Insufficient and/or erroneous sound velocity information, which is usually due to too widely spaced or non-existent velocity profiles within an area, results in an under or over-estimate of water depth which increases with distance from the center of the swath. The bathymetric data were also corrected to mean lower low water (MLLW) using a discrete tidal-zoning model (DTZ) developed by NOAA/NOS's Hydrographic Planning Team (Huang, personal communication, 2010) (.). The DTZ model corrects differences in tidal phase and amplitude between the survey area and observations made at NOS tide gauges at Gulfport Harbor (8745557) and Pascagoula NOAA Lab (8741533). The tidal zone models were imported into CARIS (version: HIPS and SIPS 6.1) as text files and used to correct tidal observations for each survey. Once the tidal zone model was imported into CARIS using the tide editor, the tidal range and phase offsets were applied and remerged in CARIS(version: HIPS and SIPS 6.1), making all the soundings relative to MLLW. A 5-meter base surface of tide corrected bathymetric soundings was created in CARIS, then exported as ASCII x,y,z data. Source_Used_Citation_Abbreviation: CARIS (version: HIPS and SIPS 6.1; service pack 2) Process_Date: 2010 Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Elizabeth A. Pendleton Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Rd. City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Contact_Voice_Telephone: (508) 548-8700x2259 Contact_Facsimile_Telephone: (508) 457-2310 Contact_Electronic_Mail_Address: ependleton@usgs.gov Process_Step: Process_Description: The 5-m ASCII x,y,z file (for each cruise; St. Pete and WHSC) was gridded in GMT (version: 4.2.1; Wessel and Smith, 1998) using 'blockmedian' with a cell size of 50 meters. This routine was conducted to minimize edge effects in the 'surface' gridding routine because these data were collected at approximately 40-50% seafloor coverage. Next a tension spline routine (at 0.1) in GMT was used ('surface') to create a netCDF grid (*.grd or *.nc). Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Elizabeth A. Pendleton Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Rd. City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Contact_Voice_Telephone: (508) 548-8700 x2259 Contact_Facsimile_Telephone: (508) 457-2310 Contact_Electronic_Mail_Address: ependleton@usgs.gov Process_Step: Process_Description: The GMT grid (*.grd) was then converted to an ESRI Binary Grid via Mirone (version 1.5.0; Luis, 2007) and Matlab R2007b (version 7.5.0.342) - save grid as - ArcGIS binary grid. The projection was defined in ArcMap (version: 9.3) using Data Management Tools - Projections and Transformations - Define Projection: UTM, zone 16N, WGS84 Datum. Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Elizabeth A. Pendleton Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: U.S. Geological Survey Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543 Contact_Voice_Telephone: (508)-548-8700 x2259 Contact_Facsimile_Telephone: (508)-457-2310 Contact_Electronic_Mail_Address: ependleton@usgs.gov Process_Step: Process_Description: The ESRI Binary Grid was converted to an ASCII grid with an ESRI header using ArcToolbox (version 9.3; build 1850) -- Conversion Tools -- From Raster -- Raster to ASCII; in order to distribute these data via zipped files. Process_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Elizabeth A. Pendleton Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: U.S. Geological Survey Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543 Contact_Voice_Telephone: (508)-548-8700 x2259 Contact_Facsimile_Telephone: (508)-457-2310 Contact_Electronic_Mail_Address: ependleton@usgs.gov Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Raster Raster_Object_Information: Raster_Object_Type: Pixel Row_Count: 221 Column_Count: 861 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: 0.999600 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: 50.000000 Ordinate_Resolution: 50.000000 Planar_Distance_Units: meters Geodetic_Model: Horizontal_Datum_Name: D_WGS_1984 Ellipsoid_Name: WGS_1984 Semi-major_Axis: 6378137.000000 Denominator_of_Flattening_Ratio: 298.257224 Vertical_Coordinate_System_Definition: Depth_System_Definition: Depth_Datum_Name: Mean lower low water Depth_Resolution: 0.1 meters Depth_Distance_Units: meters Entity_and_Attribute_Information: Distribution_Information: Distributor: Contact_Information: Contact_Person_Primary: Contact_Person: Elizabeth A. Pendleton Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Rd. City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Contact_Voice_Telephone: (508) 548-8700x2259 Contact_Facsimile_Telephone: (508) 457-2310 Contact_Electronic_Mail_Address: ependleton@usgs.gov Resource_Description: Downloadable Data Distribution_Liability: Neither the U.S. Government, the Department of the Interior, nor the USGS, nor any of their employees, contractors, or subcontractors, make any warranty, express or implied, nor assume any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, nor represent that its use would not infringe on privately owned rights. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of these data or related materials. Any use of trade, product, or firm 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: WinZip Format_Version_Number: 14.0 Format_Information_Content: WinZip file containing an ESRI ASCII grid of swath bathymetric data collected offshore of the Gulf Islands, MS, and the associated metadata. File_Decompression_Technique: Use WinZip or pkUnzip Transfer_Size: 371 KB Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://pubs.usgs.gov/of/2010/1178/GIS_catalog/Bathy/bathy_grd.zip Access_Instructions: Data can be downloaded via the World Wide Web (WWW) Offline_Option: Offline_Media: DVD-ROM Recording_Capacity: Recording_Density: 4.75 Recording_Density_Units: Gbytes Recording_Format: UDF Fees: None Technical_Prerequisites: The grid contained in the GIS_catalog.zip file is available as an ESRI binary grid. To utilize this data, the user must have a GIS software package capable of reading an ESRI binary grid. The grid contained in the bathy_grd.zip file is available as an ASCII grid with an ESRI header. To utilize this data, the user must have a GIS software package capable of reading ASCII grids with ESRI headers, or be able to manipulate an ASCII matrix with a geospatial header. The ASCII raster files can be easily converted to ESRI grid format in either ArcView with Spatial Analyst extension (Import Data Source: ASCII Raster) or ArcGIS with Spatial Analyst extension (ASCII to Raster). The user should select floating point grid (as opposed to integer grid) when converting the bathymetry data. Metadata_Reference_Information: Metadata_Date: 20101022 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Elizabeth A. Pendleton Contact_Organization: U.S. Geological Survey Contact_Position: Geologist Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Country: USA Contact_Voice_Telephone: 508-548-8700 x2259 Contact_Facsimile_Telephone: (508)-457-2310 Contact_Electronic_Mail_Address: ependleton@usgs.gov Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Time_Convention: local time Metadata_Access_Constraints: None Metadata_Use_Constraints: None Metadata_Extensions: Online_Linkage: http://www.esri.com/metadata/esriprof80.html Profile_Name: ESRI Metadata Profile Lineage: