This grid represents interpolated data; processed to account for gaps that occurred along-track and between adjacent lines.
Nearly all quality main survey line bathymetric data (generally shore parallel for the USGS surveys) that were collected within the Buzzards Bay survey area were incorporated in this grid. Approximately 340 square-km of additional bathymetric data collected within Vineyard Sound, Massachusetts during these field activities were published in USGS Open-File Report 2012-1006 High-Resolution Geophysical Data from the Inner Continental Shelf: Vineyard Sound, Massachusetts (
http://pubs.usgs.gov/of/2012/1006/).
Soundings from the USGS surveys were processed and edited using Computer Aided Resource Information System (CARIS) Hydrographic Information Processing System (HIPS; ver. 6.1 and 7.1). Although the soundings were manually edited, small data spikes may exist at outer edges of some swaths. In addition, small gaps between adjacent survey lines may exist, especially in depth less than 14 meters. Tielines and transit lines were generally excluded from this grid if quality main survey line data were available. The tieline and transit line data were used to verify tide corrections during post-processing.
NOAA's CARIS directory for survey H11319 was provided to the USGS. No additional swath processing or navigation editing was performed to the NOAA data in CARIS.
Horizontal_Positional_Accuracy:
Horizontal_Positional_Accuracy_Report:
Hydrographic survey H11319: Horizontal sounding positional control for the NOAA H11319 survey was determined using the Global Positioning System (GPS) corrected by U.S. Coast Guard Differential GPS (DGPS) beacon stations. The primary DGPS beacon used for survey H11319 was at Acushnet, MA and the secondary beacon was at Portsmouth, NH. No horizontal control stations were established for the NOAA survey. Additional information may be found in the NOAA Descriptive Report for survey H11319 and the Data Acquisition and Processing Report.
Field activities 2009-002-FA and 2010-004-FA: Navigation was acquired with a Coda Octopus F180 Differential Global Positioning System + Wide Area Augmentation System (DGPS+WAAS), which is accurate to + or - 1 to 2 meters, horizontally. All DGPS data are referenced to WGS84. The SWATHPlus transducers were mounted on a rigid pole, approximately 2.46 m below the water line, along the starboard side of the M/V Megan T. Miller. The DGPS antenna was located on the same pole approximately 4.3m above the sea surface. These offsets were corrected within the SWATHPlus acquisition software.
Field activity 2011-004-FA: Navigation was acquired with a Coda Octopus F180 Differential Global Positioning System + Wide Area Augmentation System (DGPS+WAAS), which is accurate to + or - 1 to 2 meters, horizontally. All DGPS data are referenced to WGS84. The SWATHPlus transducers were mounted on a rigid pole, approximately 2.17 m below the water line, along the port side of the M/V Scarlett Isabella. The DGPS antenna was located on the same pole approximately 4.6m above the sea surface. These offsets were corrected within the SWATHPlus acquisition software.
The DGPS horizontal positional accuracy is estimated to be within 3-5 m; WAAS enabled DGPS accuracy is estimated to be within less than 3 m and the accuracy of RTK-GPS (which was not applied to the horizontal positions for these surveys) is estimated to be less than 1 m. However, the U.S. Coast Guard maintains a maritime DGPS service providing 10 meter accuracy for the coastal areas of the continental US; therefore, a very conservative, worse-case estimate of the horizontal positional accuracy of this survey data is approximately 10 meters (although these systems have been shown to be reliable to less than 2m). (sources:
http://www.noaa.gov;
http://www.nos.noaa.gov;
http://www.ngs.noaa.gov;
http://www.nstb.tc.faa.gov/;
http://www.navcen.uscg.gov).
Vertical_Positional_Accuracy:
Vertical_Positional_Accuracy_Report:
NOAA Hydrographic survey H11319: NOAA's National Ocean Service Hydrographic Surveys Specifications and Deliverables closely follow the International Hydrographic Organizations Standards for Hydrographic Surveys, Reference tests conducted in the summer 2004 showed that the NOAA Ship RUDE's sonar system exceeded the International Hydrographic Organization's "Special Order" specification. Position and attitude on the NOAA Ship Rude was measured using TSS POS/MV 320 and a Trimble DSM-212L DGPS receiver. A SeaBird SBE 19 SEACAT conductivity, temperature and depth (CTD) profiler was used to measure sound-velocity data. The tidal datum for survey H11319 is Mean Lower Low Water (MLLW). Tidal corrections were calculated using verified data from tidal station #8452660 at Newport, RI, and final corrected soundings (from a zoned tidal model) were referenced to MLLW (NOAA DAPR, 2004; NOAA DR, 2004). Refer to the NOAAShipRUDE2004 Data Acquisition and Processing Report (DAPR) and the Horizontal and Vertical Control Report in the Descriptive Report, for detailed equipment, vessel configuration and setting information.
USGS field activities 2009-002-FA, 2010-004-FA and 2011-004-FA: Vertical accuracy of the raw data based on system specifications may approximate 1% of water depth, 0.1 to 0.4 meters within the survey area. However, overall vertical accuracies on the order of 50cm or better are assumed based on the following considerations: The Coda Octopus F180 Attitude and Positioning system, used to correct for vessel roll, pitch, heave, and yaw, has a theoretical vertical accuracy of a few mm. Tidal offsets were corrected to MLLW using Real-Time Kinematic GPS (RTK-GPS) heights in post-processing (see process steps). Corrections were sent via cellular modem and VHF radio to the ship from the base station on land. The primary reference station is located at the USGS Marine Operations Facility (MOF) in Falmouth, MA. USGS field tests (unpublished) using submerged targets suggest that the vertical accuracy of the RTK-GPS tidal correction is less than 30cm. Refraction artifacts were minimized by acquiring a range of sound velocity profiles with a hand-casted Applied MicroSystems SV Plus sound velocimeter during survey 2009-002-FA and an ODIM MVP30 moving vessel profiler during surveys 2010-004-FA and 2011-004-FA. Sound velocity data are entered into the SWATHPlus acquisition software to model the sound velocity structure of the water column. Gridding algorithms and cell sizes for these data could introduce errors as great as 3m along the edges of the data, but gridding-induced errors are likely much smaller (less than 20cm) for most of the survey area. Changes in ship draft due to water and fuel usage were not considered.
Source_Information:
Source_Citation:
Citation_Information:
Originator: U.S. Geological Survey
Publication_Date: Unpublished Material
Title: raw bathymetry data
Type_of_Source_Media: disc
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20090528
Ending_Date: 20110513
Source_Currentness_Reference:
ground condition of individual surveys on the following dates: 20090528-20090618; 20100515-20100520; 20110513
Source_Citation_Abbreviation: none
Source_Contribution:
This bathymetric dataset is a combination of data collected by the USGS (with a 234 kHz Systems Engineering and Assessment Ltd. (SEA) SWATHplus interferometric sonar mounted on the M/V Megan T. Miller (2009 and 2010) and the M/V Scarlett Isabella (2011)). Data were acquired between May 2009 and May 2011.
USGS Configuration:
Survey: Survey lines were run at an average speed of 5 knots and were spaced 50-100 m apart to obtain overlapping swaths of data and full seafloor coverage.
Sonar: The SEA SWATHplus-M operates at a frequency of 234 kHz and a variable range (increased or decreased manually depending on water depth). The system was operated with a transmit power: 80 percent, a transmit length: 12 cycles (2009-002-FA and 2010-004-FA) or 43 cycles (2011-004-FA), 3072 samples per channel (2009-002-FA) or 4096 samples per channel (2010-004-FA and 2011-004-FA), and a variable range (increased or decreased depending on water depth).
Speed of Sound: Sound-velocity profiles were collected approximately every 2 hours by hand casted Applied MicroSystems SV Plus sound velocimeter (2009-002-FA), or an ODIM MVP30 moving vessel profiler (2010-004-FA and 2011-004-FA).
Tides: Tides were typically corrected during post-processing using one- or two-minute interval averages of the RTK tide data recorded in the "TID" message string of the HYPACK navigation file for each line (however; RTK signal dropouts during survey 2009-002-FA and 2010-004-FA made it necessary to post-process the base and rover navigation data using NovAtel GrafNav (version: 8.30.1123) to calculate the RTK tide offset values, see process steps for more details).
While much effort was devoted to cleaning the data and minimizing survey artifacts, some artifacts may still be seen in the final gridded data including an along track artifact at nadir (the ship track) and at the far edges of a survey line where adjacent swaths overlap. These artifacts are especially noticeable in areas of little local relief.
Source_Information:
Source_Citation:
Citation_Information:
Originator:
National Oceanic and Atmospheric Administration, National Ocean Service
Publication_Date: Unpublished Material
Title: CARIS HIPS database of bathymetry data
Type_of_Source_Media: disc
Source_Time_Period_of_Content:
Time_Period_Information:
Range_of_Dates/Times:
Beginning_Date: 20040330
Ending_Date: 20040412
Source_Currentness_Reference:
ground condition of individual survey on the following dates: 20040330-20040412
Source_Citation_Abbreviation: none
Source_Contribution:
This bathymetric dataset is data collected by the NOAA (with a 455 kHz multibeam-echosounder mounted on the NOAA Ship RUDE(2004)). Data were acquired in March and April 2004.
NOAA Configuration:
Survey: All data were collected by the NOAA Ship RUDE. Trackline spacing for survey H11319 was based on a estimate of 2.5 times the water depth to achieve overlapping swaths for full seafloor coverage. For this area survey lines were typically between 25-50m apart. Ship speed was determined such that the survey achieved a sampling rate of 3.2 pings per 3 meters of along track distance.
Sonar: The RESON SeaBat 8125 is a 0.5 degree (across-track) by 1 degree (along-track) beam angle system which operates at a frequency of 455 kHz and collects 240 individual soundings in a swath oriented perpendicular to the vessel track. The system is capable of ping rates ranging from 3.02 Hz to 40.05 Hz but for this survey, the maximum ping rate was set to 20 Hz.
Speed of Sound: SeaBird SBE 19 SEACAT conductivity, temperature and depth (CTD) profiler was used to measure sound-velocity data.
Tides: The tidal datum for survey H11319 is Mean Lower Low Water (MLLW). Tidal corrections were calculated using verified data from tidal station #8452660 at Newport, RI, and final corrected soundings (from a zoned tidal model) were referenced to MLLW.
Other: All bathymetry processing, including tide-correction, were done by NOAA Hydrographers. NOAA's Computer Aided Resource Information System (CARIS) directory was provided to the USGS. Refer to the Fall Data Acquisition and Processing Report (DAPR) and the Horizontal and Vertical Control Report, for detailed equipment, vessel configuration and setting information.
Only the data necessary to fill gaps in the 2009-2011 USGS bathymetry survey data were used. Although the CARIS database contains the "raw" bathymetry soundings, it also contains any of the soundings and navigation edits, refraction and tide corrections, and motion reference unit offsets that were done by NOAA hydrographers. All NOAA-provided edits, corrections, and offsets were used in the final bathymetry grid for Buzzards Bay. No additional editing was done to the NOAA-provided data.
Process_Step:
Process_Description:
1. Raw to Processed conversion for USGS field activity 2009-002-FA, 2010-004-FA and 2011-004-FA: Each raw SWATHPlus bathymetric sonar file (sxr) was converted to a SWATHPlus processed file (sxp) using SEA SWATHPlus Swath Processor (vers. 3.06 in 2009 and 2010 and ver. 3.07 in 2011). 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. Several bathymetric filters were applied to remove erroneous soundings and reduce the density of the data. Predicted tidal information was merged into the processed file (sxp) during this conversion, however observed tidal corrections were applied later in the processing flow.
Bathymetric filtering typically included low amplitude (100%), range (0-4m), box (3-50m depth, 1.5-75m horizontal), median (window size 5), alongtrack 1 (depth difference of 5-m, window size 5-m, and learn rate of 0.7), alongtrack 2 (depth difference of 1.5-m, window size 1m, and learn rate of 0.9), and mean filters (0.25m). These represent the typical parameters used for the majority of the USGS survey although the values may have been adjusted slightly for specific parts of the survey area. Processing occurred in 2009, 2010, and 2011.
Process_Date: 2011
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Seth Ackerman
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
Country: USA
Contact_Voice_Telephone: 508-548-8700 x2315
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: sackerman@usgs.gov
Process_Step:
Process_Description:
2. CARIS processing for USGS field activity 2009-002-FA, 2010-004-FA and 2011-004-FA: A new CARIS HIPS project (vers. 6.1 and 7.1) was created for each field activity with projection information set to Universal Transverse Mercator (UTM) Zone 19, WGS84. 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 reviewed and edited as needed using the navigation editor tool. Beam-to-beam slopes and across track angle filters were applied to the soundings line by line. The refraction editor was used to adjust sound speed values in areas where velocimeter data did not adequately correct depth profiles obviously influenced by local anomalies in speed of sound through the water column.
CARIS processing for NOAA hydrographic survey H10993: The CARIS HIPS directory was received from the National Oceanic and Atmospheric Administration - National Geophysical Data Center (NOAA-NGDC). The multibeam bathymetric data from NOAA was delivered fully processed and tide-corrected by NOAA Hydrographers. The CARIS HIPS project was reviewed and checked for any inconsistencies. Survey lines that were not needed to create a complete gridded surface for the Buzzards Bay survey area were removed from the project. Processing occurred in 2009, 2010, and 2011.
Process_Date: 2011
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Seth Ackerman
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
Country: USA
Contact_Voice_Telephone: 508-548-8700 x2315
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: sackerman@usgs.gov
Process_Step:
Process_Description:
3. Prepare and apply RTK Tide data for USGS field activities 2009-002-FA, 2010-004-FA and 2011-004-FA:
Tides files were created during post-processing using one- or two-minute interval averages of the RTK tide data recorded in the "TID" message string of the HYPACK navigation file for each line. The TID messages from DEV 1 (which was the Ashtech Z-Extreme during survey 2009-002-FA and the NovAtel DL-V3 receiver during surveys 2010-004-FA and 2011-004-FA) were used to extract the tide offset values. This was done using a shell script called getNovatelTides and an AWK script called parseHypackNovatelTides.awk
However; RTK signal dropouts during parts of surveys 2009-002-FA and 2010-004-FA made it necessary to post-process the base station and rover navigation data using NovAtel GrafNav (version: 8.30.1123). This process calculates the RTK tide offset values, using the height data recorded separately by the Master/Base station (which was set up at the USGS Marine Operations Facility) and the Remote/Rover station (the GPS antennea on the survey vessel). RTK tide data processed with GrafNav were then formatted for input into CARIS using a Perl script parse_GrafNav_files.pl.
The tide (.tid) files for each survey were finalized by using data from either the GrafNav processed or the HYPACK extracted tide data.
In Buzzards Bay:
RTK tidal corrections for Survey 2009-002-FA were post-processed from base-station and rover data using GrafNav, except for discrete periods of JD152 (1200-2359), JD158 (0000-1516 and 2353-2359), JD159 (0000-2400), and JD160 (0000-0145) where HYPACK extracted tides were used.
Only HYPACK extracted tide data were used for Survey 2010-004-FA.
Only HYPACK extracted tide data were used for Survey 2011-004-FA.
RTK tide corrections were loaded and applied to the soundings line by line in CARIS. Each line was re-merged and the preliminary BASE surfaces were recomputed to incorporate the new tide information. Additional swath editing was done in CARIS using the swath and area based editors to remove any additional inconsistencies and minimize survey artifacts. Processing occurred in 2009, 2010, and 2011.
Process_Date: 2011
Source_Produced_Citation_Abbreviation:
09002_TID_master.tid; 10004_RTK_Tides_BBay.tid; 11004_TID_master.tid
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Seth Ackerman
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
Country: USA
Contact_Voice_Telephone: 508-548-8700 x2315
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: sackerman@usgs.gov
Process_Step:
Process_Description:
4. Final BASE surface creation: A new CARIS HIPS project was made to create final BASE surfaces for all of the bathymetric data from the NOAA and USGS surveys. A 5-meter BASE surface was created for the entire area of the Buzzards Bay survey area utilizing all the quality bathymetric soundings data from USGS surveys 2009-002-FA, 2010-004-FA and 2011-004-FA. Survey lines from NOAA hydrographic survey H10993 were added to the project and then added to the Buzzards Bay Base Surface. Processing occurred in 2011 and 2012.
Process_Date: 2012
Source_Produced_Citation_Abbreviation: CARIS HIPS BASE (BB_All)
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Seth Ackerman
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
Country: USA
Contact_Voice_Telephone: 508-548-8700 x2315
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: sackerman@usgs.gov
Process_Step:
Process_Description:
5. The CARIS HIPS BASE surface was exported from CARIS as a Bathymetry Attributed Grid (BAG) file and then imported into IVS 3D Fledermaus (version 7.3); [Import -> Import Gridded Data - BAG/Open Nav Surface]. This creates a Fledermaus SD file. Then in IVS 3D DMagic, SD file was exported to ARC/INFO ASCII GRID format (outputfile: BB_All.asc).
Process_Date: 2012
Source_Produced_Citation_Abbreviation: IVS 3D SD file (BB_All.sd)
Source_Produced_Citation_Abbreviation: ARC/INFO ASCII GRID (BB_All.asc)
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Seth Ackerman
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
Country: USA
Contact_Voice_Telephone: 508-548-8700 x2315
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: sackerman@usgs.gov
Process_Step:
Process_Description:
6. Using Esri ArcToolbox (version 9.3), converted ARC/INFO ASCII GRID to an Esri ArcRaster Grid [Conversion Tools, To Raster, ASCIIToRaster] creating final bathymetry grid "BB_bathy5m".
Process_Date: 2012
Source_Produced_Citation_Abbreviation: Esri ArcRaster Grid (BB_bathy5m)
Process_Contact:
Contact_Information:
Contact_Person_Primary:
Contact_Person: Seth Ackerman
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
Country: USA
Contact_Voice_Telephone: 508-548-8700 x2315
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: sackerman@usgs.gov
Process_Step:
Process_Description:
Edits to the metadata were made to fix any errors that MP v 2.9.32 flagged. This is necessary to enable the metadata to be successfully harvested for various data catalogs. In some cases, this meant adding text "Information unavailable" or "Information unavailable from original metadata" for those required fields that were left blank. Other minor edits were probably performed (title, publisher, publication place, etc.). The distribution format name was modified in an attempt to be more consistent with other metadata files of the same data format. The metadata date (but not the metadata creator) was edited to reflect the date of these changes. The metadata available from a harvester may supersede metadata bundled within a download file. Compare the metadata dates to determine which metadata file is most recent.
Process_Date: 20151208
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: VeeAnn A. Cross
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: mailing and physical address
Address: 384 Woods Hole Rd
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543
Contact_Voice_Telephone: 508-548-8700 x2251
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description: USGS Thesaurus keywords added to the keyword section.
Process_Date: 20180720
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: VeeAnn A. Cross
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: Mailing and Physical
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: 508-548-8700 x2251
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description: Crossref DOI link was added as the first link in the metadata.
Process_Date: 20191118
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: VeeAnn A. Cross
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: Mailing and Physical
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: 508-548-8700 x2251
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
Process_Step:
Process_Description:
Added keywords section with USGS persistent identifier as theme keyword.
Process_Date: 20200908
Process_Contact:
Contact_Information:
Contact_Organization_Primary:
Contact_Organization: U.S. Geological Survey
Contact_Person: VeeAnn A. Cross
Contact_Position: Marine Geologist
Contact_Address:
Address_Type: Mailing and Physical
Address: 384 Woods Hole Road
City: Woods Hole
State_or_Province: MA
Postal_Code: 02543-1598
Contact_Voice_Telephone: 508-548-8700 x2251
Contact_Facsimile_Telephone: 508-457-2310
Contact_Electronic_Mail_Address: vatnipp@usgs.gov
