Identification_Information: Citation: Citation_Information: Originator: Page C. Valentine Originator: Jessica L. Baker Originator: Tanya S. Unger Publication_Date: 2005 Title: bcksctter.tif: Backscatter intensity and sun-illuminated topographic imagery of the seafloor in the Stellwagen Bank National Marine Sanctuary region. Edition: 1.0 Geospatial_Data_Presentation_Form: remote-sensing image Series_Information: Series_Name: Scientific Investigations Map Issue_Identification: 2840 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/sim/2005/2840/data/backscatter/bcksctter.zip Larger_Work_Citation: Citation_Information: Originator: Page C. Valentine, editor Publication_Date: 2005 Title: Sea floor image maps showing topography, sun-illuminated topography, backscatter intensity, ruggedness, slope, and the distribution of boulder ridges and bedrock outcrops in the Stellwagen Bank National Marine Sanctuary region off Boston, Massachusetts Edition: 1.0 Series_Information: Series_Name: Scientific Investigations Map Issue_Identification: 2840 Publication_Information: Publication_Place: Woods Hole Science Center, Woods Hole, MA Publisher: U.S. Geological Survey, Coastal and Marine Geology Program Other_Citation_Details: 1:60,000, 6 maps, 12 sheets Online_Linkage: http://pubs.usgs.gov/sim/2005/2840/ Description: Abstract: This data set contains the sun-illuminated topographic imagery and backscatter intensity generated from a multibeam sonar survey of the Stellwagen Bank National Marine Sanctuary region off Boston, Massachusetts, an area of approximately 1100 square nautical miles. The Stellwagen Bank NMS Mapping Project is designed to provide detailed maps of the Stellwagen Bank region's environments and habitats and the first complete multibeam topographic and sea floor characterization maps of a significant region of the shallow EEZ. Data were collected on four cruises over a two year period from the fall of 1994 to the fall of 1996. The surveys were conducted aboard the Canadian Hydrographic Service vessel Frederick G. Creed, a SWATH (Small Waterplane Twin Hull) ship that surveys at speeds of up to 16 knots. The multibeam data were collected utilizing a Simrad Subsea EM 1000 Multibeam Echo Sounder (95 kHz) that is permanently installed in the hull of the Creed. Purpose: Development of interpretive seabed maps, sea floor imagery, and a GIS database that are accessible to scientists, policymakers, managers, and the general public. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 1994 Ending_Date: 1998 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: As needed Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -70.600 East_Bounding_Coordinate: -70.0333 North_Bounding_Coordinate: 42.800 South_Bounding_Coordinate: 42.0833 Keywords: Theme: Theme_Keyword_Thesaurus: General Theme_Keyword: Geographic Information Systems Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Theme_Keyword: Coastal and Marine Geology Program Theme_Keyword: CMGP Theme_Keyword: Woods Hole Science Center Theme_Keyword: WHSC Theme_Keyword: SIMRAD SUBSEA EM 1000 Theme_Keyword: Frederick G. Creed Theme_Keyword: Multibeam Echo Sounder Theme_Keyword: Sea floor topography Theme_Keyword: bathymetry Theme_Keyword: shaded relief imagery Theme_Keyword: backscatter intensity Theme_Keyword: psuedo color encoded Theme_Keyword: GeoTIFF image Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: oceans and estuaries Theme_Keyword: geoscientificInformation Theme_Keyword: imageryBaseMapsEarthCover Theme_Keyword: elevation Place: Place_Keyword_Thesaurus: General Place_Keyword: Massachusetts Place_Keyword: MA Place_Keyword: Stellwagen Bank National Marine Sanctuary Place_Keyword: SBNMS Place_Keyword: Shallow EEZ Place_Keyword: EEZ Place_Keyword: Gulf of Maine Place_Keyword: Atlantic Ocean Place_Keyword: North Atlantic Place_Keyword: Boston Access_Constraints: None Use_Constraints: Public domain data from the U.S. Government are freely redistributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey (USGS) as the source of this information. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Page C. Valentine Contact_Organization: U.S. Geological Survey Contact_Position: Research Geologist Contact_Address: Address_Type: mailing and physical address Address: U.S. Geological Survey Address: 384 Woods Hole Rd. City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Country: USA Contact_Voice_Telephone: (508) 548-8700 x2239 Contact_Facsimile_Telephone: (508) 457-2310 Contact_Electronic_Mail_Address: pvalentine@usgs.gov Browse_Graphic: Browse_Graphic_File_Name: http://pubs.usgs.gov/sim/2005/2840/data/backscatter/bcksctter-thumb.gif Browse_Graphic_File_Description: Thumbnail image showing backscatter intensity and sun-illuminated topography of the seafloor in Stellwagen Bank National Marine Sanctuary region. Browse_Graphic_File_Type: GIF Browse_Graphic: Browse_Graphic_File_Name: http://pubs.usgs.gov/sim/2005/2840/data/backscatter/bcksctter-browse.gif Browse_Graphic_File_Description: Browse image showing backscatter intensity and sun-illuminated topography of the seafloor in Stellwagen Bank National Marine Sanctuary region. Browse_Graphic_File_Type: GIF Native_Data_Set_Environment: Microsoft Windows XP Version 5.1 (Build 2600) Service Pack 2; ESRI ArcCatalog 9.0.0.535 Cross_Reference: Citation_Information: Originator: Page C. Valentine Originator: Tammie J. Middleton Originator: Sarah J. Fuller Publication_Date: 2001 Title: Sea floor maps showing topography, sun-illuminated topography, and backscatter intensity of the Stellwagen Bank National Marine Sanctuary region off Boston, Massachusetts Edition: 1.01 Series_Information: Series_Name: Open-File Report Issue_Identification: 00-410 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/of00-410/ Cross_Reference: Citation_Information: Originator: Page C. Valentine Originator: Jessica L. Baker Originator: Tanya S. Unger Publication_Date: 2003 Title: Backscatter intensity and sun-illuminated sea Floor topography of the Stellwagen Bank National Marine Sanctuary off Boston, Massachusetts Edition: 1.0 Geospatial_Data_Presentation_Form: map Series_Information: Series_Name: Geologic Investigations Map Issue_Identification: I-2676-C Publication_Information: Publication_Place: Woods Hole Science Center, Woods Hole, MA Publisher: U.S. Geological Survey, Coastal and Marine Geology Program Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The ship's position was determined with an accuracy of 10 m or better using a Magnavox 4200 geographic positioning system (GPS) receiver in conjunction with differential GPS corrections transmitted by U.S. Coast Guard radio beacons. At the start of each day, casts were made to record the sound velocity profile of the water column in the area to be surveyed. This information is used by the data acquisition system to correct for the refraction of the transmitted multibeam sound signal as it travels through the water to and from the sea floor. Logical_Consistency_Report: Multibeam echo sounder data was collected aboard the Canadian Hydrographic Service vessel Frederick G. Creed, an aluminum SWATH (Small Waterplane Area Twin Hull) ship that surveys at speeds up to 16 knots. The ship has two submerged torpedo-shaped hulls that support the main deck via two thin struts. This design reduces wave motion on the ship and resistance to the ship's forward motion through the water, thus making it a very stable platform at high survey speeds. Stability of the ship is also enhanced by the computer-controlled action of four stabilizer fins located fore and aft on the inboard side of the hulls. The stabilizers control the pitch and roll of the vessel and allow adjustment of the heel and trim of the ship while under way. An Applied Analytics POS/MV motion sensor located in the hull near the EM 1000 transducer detects changes in pitch, roll, and heave of the vessel. The motion information is recorded concurrently with the acquired multibeam signal and both are logged in a single file on the Sun workstation and made available to other workstations for further processing. Completeness_Report: The sidescan-sonar backscatter data are displayed in real time on the Sun workstation using software designed and written by the Ocean Mapping Group, University of New Brunswick. This display allows data gaps to be identified during the survey and also gives a measure of the data quality. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Sounding rates depend on water depth but vary from 2 to 4 per second in water depths less than 100 meters. Horizontal spatial resolution at these sounding rates is on the order of 10% of the water depth at 16 knots; however, vertical resolution is approximately 1% or better in the same depth range. Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: Sounding rates depend on water depth but vary from 2 to 4 per second in water depths less than 100 meters. Horizontal spatial resolution at these sounding rates is on the order of 10% of the water depth at 16 knots; however, vertical resolution is approximately 1% or better in the same depth range. Lineage: Process_Step: Process_Description: Multibeam data were processed using SwathEd, a suite of multibeam software editing and display tools developed by Dr. John Hughes Clarke of the Ocean Mapping Group, University of New Brunswick (UNB). Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Raster Raster_Object_Information: Raster_Object_Type: Pixel Row_Count: 6199 Column_Count: 3631 Vertical_Count: 1 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Map_Projection: Map_Projection_Name: Mercator Mercator: Standard_Parallel: 41.650000 Longitude_of_Central_Meridian: -70.316667 False_Easting: 0 False_Northing: 0 Planar_Coordinate_Information: Planar_Coordinate_Encoding_Method: row and column Coordinate_Representation: Abscissa_Resolution: 13.000000 Ordinate_Resolution: 13.000000 Planar_Distance_Units: meters Geodetic_Model: Horizontal_Datum_Name: North American Datum of 1983 Ellipsoid_Name: Geodetic Reference System 80 Entity_and_Attribute_Information: Overview_Description: Entity_and_Attribute_Overview: Backscatter imagery combines the sun-illuminated topography with the backscatter intensity (shown here in color) of the sea floor. Backscatter intensity is a measure of the hardness and roughness of the sea floor as determined from the strength of sound waves reflected from the seabed during the survey. High-backscatter materials (red and orange) are coarse sand, gravel (including piles and ridges of boulders), and rock outcrops. Moderate backscatter (green) represents sand or muddy sand. Low backscatter (blue) represents sandy mud and mud. These interpretations apply best in region's of low regional topography, because steep slopes can divert the paths of some of the reflected sound waves away from the survey vessel. Thus, seabed that slopes steeply away from the survey track can produce a lower backscatter intensity than if it were level. Unnatural-looking stripes and patterns oriented parallel or perpendicular to survey track lines are artifacts of data collection. Blank areas represent places where no data exists. Distribution_Information: Distributor: Contact_Information: Contact_Person_Primary: Contact_Person: Page C. Valentine Contact_Organization: U.S. Geological Survey Contact_Position: Research Geologist Contact_Address: Address_Type: mailing and physical address Address: U.S. Geological Survey Address: 384 Woods Hole Rd. City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Country: USA Contact_Voice_Telephone: (508) 548-8700 x2239 Contact_Facsimile_Telephone: (508) 457-2310 Contact_Electronic_Mail_Address: pvalentine@usgs.gov Resource_Description: Downloadable Data Distribution_Liability: Although these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data. 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: TIFF Format_Specification: GeoTIFF Format_Information_Content: A zip archive containing the GeoTIFF image, associated world file, and metadata. File_Decompression_Technique: zip Transfer_Size: 0.000 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://pubs.usgs.gov/sim/2005/2840/data/backscatter/bcksctter.zip Offline_Option: Offline_Media: DVD-ROM Recording_Capacity: Recording_Density: 4.75 Recording_Density_Units: Gbytes Recording_Format: UDF Fees: None Technical_Prerequisites: This image is available as a GEOTIFF image with an accompanying world file. To utilize this data, the user must have an image viewer, image processing or GIS software package capable of importing a GeoTIFF image. Metadata_Reference_Information: Metadata_Date: 20050822 Metadata_Review_Date: 20050822 Metadata_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Page C. Valentine Contact_Position: Research Geologist Contact_Address: Address_Type: mailing and physical address Address: U.S. Geological Survey Address: 384 Woods Hole Rd. City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Country: USA Contact_Voice_Telephone: (508) 548-8700 x2239 Contact_Facsimile_Telephone: (508) 457-2310 Contact_Electronic_Mail_Address: pvalentine@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