2005011314532500FALSE20050513113221002005051311322100{5399DB14-0575-4D28-BA02-9405B68CC6E4}Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.0.0.535enPulley Ridge is a series of drowned barrier islands that extends almost 200 km in 60-100 m water depths. This drowned ridge is located on the Florida Platform in the southeastern Gulf of Mexico about 250 km west of Cape Sable, Florida. This barrier island chain formed during the initial stage of the Holocene marine transgression. These islands were then submerged and left abandoned near the outer edge of the Florida Platform. The southern portion of Pulley Ridge hosts zooxanthellate scleractinian corals, green, red and brown macro algae, and a mix of deep and typically shallow-water tropical fishes. This reef community is in unusually deep water, and its extent and the controls on its distribution were unknown. To address these questions scientists from the U.S. Geological Survey Coastal and Marine Geology Program in cooperation with scientists from the University of South Florida Department of Marine Sciences have completed a detailed mapping of the southernmost 35 km of Pulley Ridge. The area was mapped using multibeam bathymetry, sidescan-sonar imagery, and high-resolution seismic-reflection profiling to define the geologic framework on which the reef is established. Submersible dives, remotely operated vehicle (ROV) transects, and transects of bottom photographs and video were collected to identify the corals and to map their distribution. This extensive suite of data has been compiled and preliminary analysis of the data suggests that the reefs are not tied to the ridge system, but instead are more broadly distributed. Whether reef distribution is controlled by oceanographic conditions or by subtle differences in the substrate that overlies the barrier island system is unclear, and are topics of continued research.This sidescan-sonar mosaic is used to map the morphology of the seafloor.David C. Twichell2005Area A (northeastern portion) Sidescan-Sonar Mosaic, Pulley Ridge: Geographic Coordinate Systemarea_a_geog.tifremote-sensing imageVeeAnn A. Crosshttp://pubs.usgs.gov/of/2005/1089/data/sidescan/geographic/area_a_geog.zipVeeAnn A. CrossDavid C. TwichellRobert B. HalleyKate T. CiembronowiczBret D. JarrettErika S. Hammar-KloseAl C. HineStan D. LockerDave F. Naarhttp://pubs.usgs.gov/of/2005/10892005GIS Compilation of Data Collected from the Pulley Ridge Deep Coral Reef RegionOpen-File Report2005-1089Woods Hole Science Center, Woods Hole, MAU.S. Geological Survey, Coastal and Marine Geology Programground condition2001090720010908None planned-83.682614-83.59750125.00141424.878594-83.682614-83.59750124.87859425.001414GeneralFloridaFlorida ShelfGulf of MexicoNorth AmericaPulley RidgeUnited StatesGeneralCMGPCoastal and Marine Geology Programcoralcoral reefOF 2005-1089Open-File Reportsidescansidescan sonarTIFFU.S. Geological SurveyUSGSWoods Hole Science CenterDF-1000field activity serial number 01010field activity identifier S-1-01-GMmosaicreefNone.The U.S. Geological Survey must be referenced as the originator of the dataset in any future products or research derived from these data.Raster DatasetDavid C. TwichellU.S. Geological SurveyOceanographermailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2266(508) 457-2310dtwichell@usgs.govUSGS image processing system: near real-time mosaicking of high-resolution sidescan-sonar dataW.W. DanforthT.F. O'BrienW.C. Schwab1991Jan. 1991Sea TechnologyArchive of sidescan-sonar data and DGPS navigation data, collected during USGS cruise SUNC01010, Pulley Ridge, Gulf of Mexico, 05 September - 12 September 2001E.S. Hammar-KloseD.C. TwichellC.R. Worley2003Open-File Report02-155Woods Hole Science Center, Woods Hole, MAU.S. Geological SurveyDigital mapping of sidescan sonar data with the Woods Hole Image Processing System softwareV.F. Paskevich1992Open-File Report92-536U.S. Geological SurveyMAPIT: An improved method for mapping digital sidescan sonar data using the Woods Hole Image Processing System (WHIPS) SoftwareV.F. Paskevich1996Open-File Report96-281U.S. Geological SurveyMicrosoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.0.0.535area_a_geog.tif-83.682614-83.59750125.00141424.8785941-83.682614-83.59750125.00141424.8785941enFGDC Content Standards for Digital Geospatial MetadataFGDC-STD-001-1998local timeVeeAnn A. CrossU.S. Geological SurveyMarine Geologistmailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2251(508) 457-2310vatnipp@usgs.gov20050513http://www.esri.com/metadata/esriprof80.htmlESRI Metadata ProfileISO 19115 Geographic Information - MetadataDIS_ESRI1.0datasetDownloadable Data63.80863.808David C. TwichellU.S. Geological SurveyOceanographermailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2266(508) 457-2310dtwichell@usgs.govThese data were prepared by an agency of the United States Government. Neither the United States government nor any agency thereof, nor any of their employees, make any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed in this report, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States government or any agency thereof. Any views and opinions of authors expressed herein do not necessarily state or reflect those of the United States government or any agency thereof. Although all data published in this report have been used by the USGS, no warranty, expressed or implied, is made by the USGS as to the accuracy of the data and related materials and/or the functioning of the software. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the USGS in the use of this data, software, or related materials.002file://\\VEECRODTXP\Projects\Reefs\GIS\sidescan\geographic\area_a_geog.tifLocal Area Network63.808Raster DatasetRasterPixel1360585490.0000100.00000981Upper LeftTRUEPackBits1pixel codesFALSETIFFGCS_North_American_1983North American Datum of 1983Geodetic Reference System 806378137.000000298.257222Decimal degreesrow and column0.0000100.000009GCS_North_American_19832185490.00001Degree136050.000009Degree20050513Sidescan-sonar imagery was collected using an EG&G DF1000 sidescan sonar system and logged to a Triton Elics QMIPS data logging computer.Erika Hammar-KloseU.S. Geological SurveyMarine Geologistmailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x23445084572310ehammark@usgs.govThe digital sidescan data were then processed and mapped to provide proper geographic locations of features identified in the imagery. The processing steps included subsampling the raw sidescan data using a median filtering routine to suppress speckle noise and reduce file size, and correct for slant-range distortion, signal attenuation, and dropped sonar lines using XSonar (Danforth et al., 1991). After these processing steps, the imagery was mapped into its proper geographic location using techniques summarized by Paskevich (1996). Individual sidescan swaths were mapped with each pixel geographically positioned at a resolution of 1 m/pixel.Erika Hammar-KloseU.S. Geological SurveyMarine Geologistmailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x23445084572310ehammark@usgs.govNon-overlapping swaths were then brought into the remote sensing software package PCI. The techniques for generating the composite digital sidescan mosaic are summarized by Paskevich (1992).Once the mosaics were completed, noise and areas of no data were trimmed from the fringes of the completed mosaic. VeeAnn A. CrossU.S. Geological SurveyMarine Geologistmailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2251(508) 457-2310vatnipp@usgs.govA linear stretch was applied in PCI to the sidescan image. This stretch was from 0-255 with resulting values between 0 and 254. This was done so that the white background (255) could be made transparent in the GIS.VeeAnn A. CrossU.S. Geological SurveyMarine Geologistmailing and physical address384 Woods Hole Rd.Woods HoleMA02543-1598(508) 548-8700 x2251(508) 457-2310vatnipp@usgs.govThe image was reprojected to geographic coordinates using BlueMarble Geographic Transformer version 5.1. The central latitude was auto-computed (24deg 56' 24.01" N).The ship was navigated with Differential GPS which has an assumed accuracy of better than 10 meters. A transponder was used to range to fish, which introduces additional positional accuracy of the sidescan imagery.30mThe pixel value represents the DN return value of the sidescan-sonar system. A high value (i.e. 254) indicates a highly reflective sea floor surface, while a low value (i.e. 0) indicates low reflectance.
All of the sidescan-sonar imagery was collected at a 600 m swath.Band_1Table256ObjectIDObjectIDOID400Internal feature number.ESRISequential unique whole numbers that are automatically generated.ValueValueInteger000RedRedDouble000GreenGreenDouble000BlueBlueDouble000