Metadata: Identification_Information: Citation: Citation_Information: Originator: U.S. Geological Survey Publication_Date: 20201210 Title: Bathymetric data collected in the Belfast Bay, Maine pockmark field using a SWATHplus-M interferometric sonar in 2006 and 2008, by the U.S. Geological Survey (32-bit floating point raster, UTM 19 WGS 84, MLLW) Edition: 1.0 Geospatial_Data_Presentation_Form: raster digital data Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P90QQCOR Publication_Information: Publication_Place: Woods Hole Coastal and Marine Science Center, Woods Hole, Massachusetts Publisher: U.S. Geological Survey, Coastal and Marine Hazards and Resources Program Online_Linkage: https://doi.org/10.5066/P90QQCOR Online_Linkage: https://www.sciencebase.gov/catalog/item/5f5f962b82ce3550e3bff23b Larger_Work_Citation: Citation_Information: Originator: Brian D. Andrews Originator: William W. Danforth Originator: Laura L. Brothers Originator: Walter A. Barnhardt Publication_Date: 2020 Title: High-resolution geophysical data collected in the Belfast Bay, Maine pockmark field in 2006, 2008, and 2009 by the U.S. Geological Survey Edition: 1.0 Series_Information: Series_Name: data release Issue_Identification: DOI:10.5066/P90QQCOR Publication_Information: Publication_Place: Reston, Virginia Publisher: U.S. Geological Survey Other_Citation_Details: Suggested citation: Andrews, B.D., Danforth, W. W., Brothers, L.L., Barnhardt, W. A., 2020, High-resolution geophysical data collected in the Belfast Bay, Maine Pockmark Field in 2006, 2008, and 2009 by the U.S. Geological Survey: U.S. Geological Survey data release, https://doi.org/10.5066/P90QQCOR Online_Linkage: https://doi.org/10.5066/P90QQCOR Online_Linkage: https://www.sciencebase.gov/catalog/item/5f59214c82cefd9f2082c15e Description: Abstract: The U.S. Geological Survey, Woods Hole Coastal and Marine Science Center in cooperation with the University of Maine mapped approximately 50 square kilometers of the seafloor within Belfast Bay, Maine. Three geophysical surveys conducted in 2006, 2008 and 2009 collected swath bathymetric (2006 and 2008) and chirp seismic reflection profile data (2006 and 2009). The project characterized the spatial, morphological and subsurface variability of the Belfast Bay, Maine pockmark field. Pockmarks are large seafloor depressions that are associated with seabed fluid escape. Purpose: This bathymetric dataset was collected to understand the morphology of the pockmark field in Belfast Bay, Maine. Supplemental_Information: These data were collected during three separate surveys: Field Activity 2006-024-FA, 12-17 Sept, 2006 https://cmgds.marine.usgs.gov/fan_info.php?fan=2006-024-FA Field Activity 2008-024-FA, 17-24 Sept, 2008 https://cmgds.marine.usgs.gov/fan_info.php?fan=2008-024-FA Field Activity 2009-037-FA, 27-30 July, 2009 https://cmgds.marine.usgs.gov/fan_info.php?fan=2009-037-FA The EdgeTech 424 seismic system became inoperable at the beginning of survey 2008-024-FA, although the survey continued collecting interferometric and sidescan sonar data. The third survey in 2009 (2009-037-FA) was conducted to collect just seismic data that was not collected during 2008-024-FA. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 20060912 Ending_Date: 20080927 Currentness_Reference: Bathymetry data were collected on the following dates: 20060912-20060917 (Julian day 255-260); 20080924-20080927 (Julian day 261-268). Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -68.971634 East_Bounding_Coordinate: -68.875830 North_Bounding_Coordinate: 44.433091 South_Bounding_Coordinate: 44.305996 Keywords: Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: U.S. Geological Survey Theme_Keyword: USGS Theme_Keyword: Coastal and Marine Hazards and Resources Program Theme_Keyword: CMHRP Theme_Keyword: Department of the Interior Theme_Keyword: DOI Theme_Keyword: Woods Hole Coastal and Marine Science Center Theme_Keyword: WHCMSC Theme_Keyword: University of Maine Theme_Keyword: R/V Rafael Theme_Keyword: bathymetry Theme_Keyword: SWATHplus-M Theme_Keyword: Interferometric Sonar Theme_Keyword: GeoTIFF Theme_Keyword: Field Activity 2006-024-FA Theme_Keyword: Field Activity 2008-024-FA Theme_Keyword: pockmarks Theme_Keyword: Marine Geology Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: oceans Theme_Keyword: elevation Theme_Keyword: geoscientificInformation Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: interferometric sonar Theme_Keyword: bathymetry Theme_Keyword: marine geology Theme_Keyword: geophysics Theme_Keyword: geospatial datasets Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:5f5f962b82ce3550e3bff23b Place: Place_Keyword_Thesaurus: None Place_Keyword: United States of America Place_Keyword: Maine Place_Keyword: Atlantic Ocean Place_Keyword: Gulf of Maine Place_Keyword: Penobscot Bay Place_Keyword: Belfast Bay Place_Keyword: Islesboro Stratum: Stratum_Keyword_Thesaurus: none Stratum_Keyword: sea floor Stratum_Keyword: seafloor Temporal: Temporal_Keyword_Thesaurus: none Temporal_Keyword: 2006 Temporal_Keyword: 2008 Access_Constraints: none Use_Constraints: Public domain data from the U.S. Government are freely re-distributable with proper metadata and source attribution. Please recognize the U.S. Geological Survey as the originator of the dataset. These data are not to be used for navigation. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Brian Andrews Contact_Organization: U.S. Geological Survey Contact_Position: Geographer Contact_Address: Address_Type: mailing and physical address Address: 384 Woods Hole Rd. City: Woods Hole State_or_Province: MA Postal_Code: 02543-1598 Country: USA Contact_Voice_Telephone: 508-548-8700 x2348 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: bandrews@usgs.gov Browse_Graphic: Browse_Graphic_File_Name: https://www.sciencebase.gov/catalog/file/get/5f5f962b82ce3550e3bff23b?name=BelfastBay_SWATHplus_bathymetry_5m_browse.jpg Browse_Graphic_File_Description: Thumbnail image of bathymetry collected in Belfast Bay, Maine. Browse_Graphic_File_Type: JPG Data_Set_Credit: Please recognize the U.S. Geological Survey (USGS) as the source of this information. Data_Quality_Information: Logical_Consistency_Report: This grid represents processed SWATHplus-M interferometric bathymetry data gridded at 5-m resolution. Quality control and data processing were conducted to remove spurious points and reduce sound speed artifacts (refraction) using Computer Aided Resource Information System (CARIS) Hydrographic Information Processing System (HIPS v. 6.1) Completeness_Report: This grid does not include all the data from the tie lines in areas of overlap with main scheme lines. Survey lines collected in 2008 that overlap with lines collected in 2006 were intended for sonar calibration and are not included in this grid. Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: These data were navigated using Real-Time Kinematic Global Positioning System (RTK-GPS) which provides horizontal positional accuracies (x and y) on the decimeter scale. The SWATHplus transducers were mounted on a rigid pole from the bow of the R/V Rafael, approximately 0.5 below waterline. Position data were recorded by Hypack Software (v. 4.3). Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: Based on SWATHplus-M interferometric sonar system specifications, vertical accuracy of the raw data may approximate 1% of water depth, which translates to 0.03 0.9 meters within the Belfast Bay survey area. RTK-GPS was used to establish water-level heights relative to Mean Lower Low Water (MLLW), providing decimeter-scale accuracies. Tide-correction was done in post-processing (see process steps). Refraction artifacts were minimized by acquiring a range of sound velocity profiles throughout the survey area to model the sound velocity structure of the water column. Changes in vessel draft due to fuel consumption was not considered. Lineage: Source_Information: Source_Citation: Citation_Information: Originator: U.S. Geological Survey Publication_Date: Unpublished Material Title: raw SWATHplus-M data in .sxr format Geospatial_Data_Presentation_Form: digital data Type_of_Source_Media: disc Source_Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 2006 Ending_Date: 2008 Source_Currentness_Reference: ground condition Source_Citation_Abbreviation: SWATHplus-M echo sounder data Source_Contribution: SONAR CONFIGURATION: Bathymetry data were collected using a Systems Engineering and Assessment Ltd. (SEA) SWATHplus-M interferometric sonar operating at a frequency of 234 kHz. The sonar transducers were mounted on a rigid pole installed on the bow of the RV Rafael and were deployed at a depth of 0.7m below the water line while collecting data. Typical sonar operating parameters include a transmit power of 9, transmit length of 28 cycles, 20148 samples per channel and a 100-meter range. A motion reference unit (TSS Ltd.) Dynamic Motion Sensor (DMS) was mounted directly above the transducers and continuously measured vertical displacement (heave), and attitude (pitch and roll) of the survey vessel during data acquisition. Data were recorded to SWATHplus-M raw format (*.sxr) using Swath Processor software. Sound-velocity profiles were collected approximately every 2 hours during the survey using a hand-casted Applied Microsystems SV Plus sound velocimeter. Real-time Kinematic Global Positioning System (RTK-GPS) navigation was used to determine the horizontal and vertical position (x,y,z) of the GPS antenna with sub-meter accuracy mounted on top of the pole. The RTK-DGPS coordinates were transmitted to the survey vessel from a land-based RTK-DGPS station established by the USGS over National Ocean Service (NOS) monument 5191-A Belfast, Penobscot Bay, Maine Process_Step: Process_Description: Step 1. PROCESS GPS TIDES Note: Processing steps 1-3 described here are the same for both of the surveys that collected bathymetry (2006-024-FA, and 2008-024-FA)the processing date reflects the most recent (2008) date. Depths were corrected to Mean Lower Low Water (MLLW) using 1 second RTK-GPS heights of the GPS antenna mounted over the SWATHplus-M sonar head. These heights were extracted from each HYPACK navigation file using the AWK script "doRTK1_by_line_FIX" and smoothed in MATLAB (version 7.20.232 R2006a) using a third order polynomial. The smoothed 1-second heights were averaged to 1-minute heights and formatted for use in CARIS HIPS using the AWK script "DoRTK2" to produce the file "TidesAllCARIS.tid" The contact person for this and all subsequent processing steps below is Brian Andrews. Process_Date: 200809 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Brian Andrews Contact_Position: Geographer 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 x2348 Contact_Facsimile_Telephone: 508-457-2310 Contact_Electronic_Mail_Address: bandrews@usgs.gov Process_Step: Process_Description: Step 2. CONVERT SXR to SXP. Each raw SWATHplus-M bathymetric sonar file (sxr) was converted to a SWATHplus processed file (sxp) using SEA SWATHplus Swath Processor (ver. 3.5.19). During the conversion process, sound velocity profiles were used to minimize potential refraction artifacts from fluctuations in the speed of sound within the water column. Various bathymetric filters were applied to eliminate sounding outliers. Process_Date: 200809 Process_Step: Process_Description: Step 3. IMPORT SXPS to CARIS HIPS. A new CARIS HIPS project (ver. 6.1) was created using the Universal Transverse Mercator (UTM) Zone 19, WGS 84 coordinate system. Each SWATHplus processed file (sxp) was imported to the new CARIS project using the Import/Conversion Wizard. A 5-meter resolution Bathymetric and Statistical Error (BASE) Surface was created from the files for each Julian day. The BASE surface for each day was reviewed for any inconsistencies or data anomalies. Navigation was edited as needed using the navigation editor tool in CARIS. Filters were applied to each line including beam to beam slopes and across track angle. The CARIS refraction editor was used to adjust the speed of sound in some cases to flatten out the depth profiles produced by localized variations in speed of sound through the water column. Process_Date: 200809 Process_Step: Process_Description: STEP 4: CREATE FINAL BASE SURFACE: A 5-m BASE surface of the entire survey area created using all the lines from 2006 and only the lines from 2008 that did not overlap with 2006 (Lines L43f1-L86f1). The final CARIS HIPS BASE (depth) surface was exported as a 32-bit floating point GeoTIFF (BelfastBay_SWATHplus_bathymetry_5m.tif) using the export context menu with in HIPS (v. 9.0.18). Process_Date: 201509 Spatial_Data_Organization_Information: Direct_Spatial_Reference_Method: Raster Raster_Object_Information: Raster_Object_Type: Pixel Row_Count: 2822 Column_Count: 1524 Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Planar: Grid_Coordinate_System: Grid_Coordinate_System_Name: Universal Transverse Mercator Universal_Transverse_Mercator: UTM_Zone_Number: 19N Transverse_Mercator: Scale_Factor_at_Central_Meridian: 0.999600 Longitude_of_Central_Meridian: -69.000000 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: 5.000000 Ordinate_Resolution: 5.000000 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 Depth_Distance_Units: meters Depth_Encoding_Method: Explicit depth coordinate included with horizontal coordinates Entity_and_Attribute_Information: Overview_Description: Entity_and_Attribute_Overview: The GeoTIFF is a 32-bit image where the pixel values represent depth in meters referenced to the mean lower low tidal datum. Depth range is between -2.72 and -87.46 meters. Entity_and_Attribute_Detail_Citation: U.S. Geological Survey Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey-ScienceBase Contact_Address: Address_Type: mailing and physical address Address: Denver Federal Center, Building 810, Mail Stop 302 City: Denver State_or_Province: CO Postal_Code: 80225 Country: USA Contact_Voice_Telephone: 1-888-275-8747 Contact_Electronic_Mail_Address: sciencebase@usgs.gov Resource_Description: Bathymetric data collected in the Belfast Bay, Maine pockmark field using a SWATHplus-M interferometric sonar in 2006 and 2008, by the U.S. Geological Survey: includes the GeoTIFF image BelfastBay_SWATHplus_bathymetry_5m.tif, the browse graphic BelfastBay_SWATHplus_bathymetry_5m_browse.jpg, and Federal Geographic Data Committee (FGDC) Content Standards for Digital Geospatial Metadata (CSDGM) metadata file BelfastBay_SWATHplus_bathymetry_5m_meta.xml). 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: GeoTIFF Format_Version_Number: CARIS HIPS Format_Specification: 32-bit GeoTIFF file Format_Information_Content: GeoTiFF image file derived from bathymetry data collected by the U.S. Geological Survey in Belfast Bay, Maine. File_Decompression_Technique: Use WinZip, 7zip, or pkUnzip Transfer_Size: 5.24 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: https://www.sciencebase.gov/catalog/item/5f5f962b82ce3550e3bff23b Network_Resource_Name: https://www.sciencebase.gov/catalog/file/get/5f5f962b82ce3550e3bff23b Network_Resource_Name: https://doi.org/10.5066/P90QQCOR Access_Instructions: The first link is to the page containing the data, the second link downloads all data available from the page as a zip file, and the third link is to the publication landing page. Fees: none Technical_Prerequisites: To utilize this data, the user must have software capable of reading a 32-bit GeoTIFF. Metadata_Reference_Information: Metadata_Date: 20201210 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Brian Andrews Contact_Organization: U.S. Geological Survey, Northeast Region Contact_Position: Geographer Contact_Address: Address_Type: mailing address Address: 384 Woods Hole Road City: Woods Hole State_or_Province: MA Postal_Code: 02543 Contact_Voice_Telephone: 508-548-8700 ext. 2348 Contact_Electronic_Mail_Address: bandrews@usgs.gov Metadata_Standard_Name: FGDC Content Standard for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998 Metadata_Time_Convention: local time