Metadata: Identification_Information: Citation: Citation_Information: Originator: U.S. Geological Survey Originator: Coastal and Marine Geology Program Publication_Date: 2013 Title: l676ar.m77t - MGD77 data file for Geophysical data from field activity L-6-76-AR in Arctic from 08/27/1976 to 09/03/1976 Geospatial_Data_Presentation_Form: tab-delimited ASCII text files Publication_Information: Publication_Place: Menlo Park, CA Publisher: U.S. Geological Survey Online_Linkage: http://www.ngdc.noaa.gov/mgg/trk/trackline/samuel_p._lee/l676ar/mgd77/ Larger_Work_Citation: Citation_Information: Originator: Wm. Clinton Steele Originator: Carolyn H. Degnan Originator: Gary B. Deeter Originator: Jean A. Riordan Publication_Date: 1980 Title: DESCRIPTION OF MARINE GEOPHYSICAL DATA COLLECTED BY THE U.S. GEOLOGICAL SURVEY AND HOW TO OBTAIN IT Edition: 1.0 Geospatial_Data_Presentation_Form: Digital Document Series_Information: Series_Name: U.S. Geological Survey Open File Report Issue_Identification: 167 Publication_Information: Publication_Place: Menlo Park, CA Publisher: U.S. Geological Survey Online_Linkage: http://pubs.usgs.gov/of/1989/0167/report.pdf Description: Abstract: Single-beam bathymetry, gravity, and magnetic data along with DGPS navigation data was collected as part of field activity L-6-76-AR in Arctic from 08/27/1976 to 09/03/1976, http://walrus.wr.usgs.gov/infobank/l/l676ar/html/l-6-76-ar.meta.html These data are reformatted from space-delimited ASCII text files located in the Coastal and Marine Geology Program (CMGP) InfoBank field activity catalog at http://walrus.wr.usgs.gov/infobank/l/l676ar/html/l-6-76-ar.bath.html, http://walrus.wr.usgs.gov/infobank/l/l676ar/html/l-6-76-ar.grav.html, and http://walrus.wr.usgs.gov/infobank/l/l676ar/html/l-6-76-ar.mag.html into MGD77T format provided by the NOAA's National Geophysical Data Center(NGDC). The MGD77T format includes a header (documentation) file (.h77t) and a data file (.m77t). More information regarding this format can be found in the publication listed in the Cross_reference section of this metadata file. Purpose: These data and information are intended for science researchers,students, policy makers, and general public. These data are not to be used for navigation purposes. The data are reformatted into MGD77T standard format for inclusion into NOAA's NGDC geophysical database. From there the data will be made available to GeoMapApp ( http://www.geomapapp.org/ ) and Virtual Ocean ( http://www.virtualocean.org/ ) Earth-browsing software. Access to the data is also provided via the USGS Coastal and Marine Geoscience Data System ( http://cmgds.marine.usgs.gov/ ). Supplemental_Information: The navigation data are digitally collected using a Satellite Integrated Navigation (SINS) system. The system is a space-based satellite navigation maintained by the United States government and is accessible using a satellite receiver. This system provides navigational accuracy of approximately 200 m.The Data Acquistion, Processing, and Storage (DAPS) group performs a number of processing steps to the navigation data once it is collected which can vary by cruise. These steps are outlined within the header information in each individual digital navigation (.05x) space-delimited ASCII data file. The header information rows are indicated by lines beginning with the character "!". There is no information on how the single-beam bathymetry, gravity, and magnetic data were collected. For each data gathering cruise leg, the available data in the following categories are forwarded to NGDC: navigation, gravity, magnetics, bathymetry, and seismic shot points. The available data for each cruise leg are re-formatted and combined into the Marine Geophysical Data Exchange Format (MGD77) and into the internal NGDC SEIS-NAV format by USGS using several USGS developed FORTRAN programs.The FORTRAN programs sample the navigation to every integer minute of the cruise. When necessary, the latitudes and longitudes are linearly interpolated. If the time between the actual navigation fixes exceeds five minutes, no data are included in the MGD77 file.To build the MGD77 file, gravity, magnetics, and bathymetry are added to this sampled navigation. When necessary, gravity, magnetics, and bathymetry data are linearly interpolated if the time between the actual data samples does not exceed five minutes. If a time gap exceeds this, the data are not reported.The navigation data are merged with the seismic shot point data in a SEIS- NAV format file. For this file, navigation data are interpolated for each shot point. Both types of files are written to magnetic tape and sent to NGDC. Time_Period_of_Content: Time_Period_Information: Range_of_Dates/Times: Beginning_Date: 19760827 Ending_Date: 19760903 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -168.31174 East_Bounding_Coordinate: -165.40790 North_Bounding_Coordinate: 67.51450 South_Bounding_Coordinate: 64.48150 Keywords: Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:60c852d8-3479-46cd-a0f0-700d97d03afd Theme: Theme_Keyword_Thesaurus: ISO 19115 Topic Category Theme_Keyword: geoscientificinformation Theme_Keyword: oceans Theme: Theme_Keyword_Thesaurus: None Theme_Keyword: Marine Geology Theme_Keyword: Marine Geophysics Theme_Keyword: Marine Gravity Field Theme_Keyword: Marine Magnetic Field Theme_Keyword: Magnetic Anomalies Theme_Keyword: Bathymetry Theme_Keyword: Water Depth Theme_Keyword: Seafloor Topography Theme: Theme_Keyword_Thesaurus: Data Categories for Marine Planning Theme_Keyword: distributions Theme_Keyword: bathymetry and elevation Theme: Theme_Keyword_Thesaurus: Marine Realms Information Bank (MRIB) keywords Theme_Keyword: single-beam echo sounder Theme_Keyword: gravimetry Theme_Keyword: magnetic field observations Theme_Keyword: marine geophysics Theme: Theme_Keyword_Thesaurus: USGS Thesaurus Theme_Keyword: single-beam echo sounder Theme_Keyword: bathymetry measurement Theme_Keyword: bathymetry Theme_Keyword: gravimeter measurement Theme_Keyword: magnetometer measurement Theme_Keyword: marine geophysics Place: Place_Keyword_Thesaurus: Geographic Names Information System (GNIS) Place_Keyword: AK Place_Keyword: Alaska Place_Keyword: Arctic Place_Keyword: Arctic Ocean Access_Constraints: None. These data are held in the public domain. Use_Constraints: This information is not intended for navigational purposes. Read and fully comprehend the metadata prior to data use. Uses of these data should not violate the spatial resolution of the data. Where these data are used in combination with other data of different resolution, the resolution of the combined output will be limited by the lowest resolution of all the data. Acknowledge the U.S. Geological Survey in products derived from these data. Share data products developed using these data with the U.S. Geological Survey.This database has been approved for release and publication by the Director of the USGS. Although this database has been subjected to rigorous review and is substantially complete, the USGS reserves the right to revise the data pursuant to further analysis and review. Furthermore, it is released on condition that neither the USGS nor the United States Government may be held liable for any damages resulting from its authorized or unauthorized use.Although this Federal Geographic Data Committee-compliant metadata file is intended to document these data in nonproprietary form, as well as in ArcInfo format, this metadata file may include some ArcInfo-specific terminology. Point_of_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Gregory K. Miller Contact_Organization: U.S. Geological Survey Contact_Position: Physical Scientist Contact_Address: Address_Type: mailing and physical Address: 600 4th Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: (727) 803-8747, ext. 3020 Contact_Electronic_Mail_Address: gmiller@usgs.gov Data_Set_Credit: Art Grantz (Chief Scientist) Cross_Reference: Citation_Information: Originator: Hittelman, Allen M., Groman, Robert C., Haworth, Richard T., Holcombe, Troy L., McHendrie, Graig, Smith, Stuart M., and Metzger, Dan R. Publication_Date: 2010 Title: The marine geophysical data exchange format - MGD77 / MGD77T Publication_Information: Publication_Place: Boulder, CO Publisher: National Geophysical Data Center, National Oceanic and Atmospheric Administration Other_Citation_Details: 25 p. Online_Linkage: http://www.ngdc.noaa.gov/mgg/dat/geodas/docs/mgd77.pdf Data_Quality_Information: Attribute_Accuracy: Attribute_Accuracy_Report: The validity or accuracy of bathymetry and navigation data is highly qualitative and depends on equipment and operating condition variables. Data quality is unknown, MGD77T files were formatted from InfoBank files identified as best available version. Logical_Consistency_Report: This data set is from one field activity with unknown instrument calibrations. Processed bathymetric depths were spot checked based on latitude and longitude against the Global Multi-Resolution Topography (GMRT) grid within GeoMapApp to ensure reasonable values. Completeness_Report: Start and end date/times of data >Navigation Data (l-6-76-ar.011 [DRS]) >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >197608271952300 197608272003000 >197608272009500 197608272319500 >197608272330010 197608272338100 >197608272355390 197608272357400 >197608280003500 197608280104140 >197608280111480 197608280526300 >197608280535500 197608280549500 >197608280556500 197608281022500 >197608281328500 197608281810000 >197608281816000 197608281844000 >197608281900200 197608282307500 >197608282345100 197608300010400 >197608300034400 197608302002100 >197608302007500 197608302015500 >197608302028100 197608302034100 >197608302043500 197609010243100 >197609010249100 197609010249100 >197609010256300 197609010641000 >197609010646400 197609030012500 >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >Gravity Data (l-6-76-ar.161_011) >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >197608272056120 197608272315120 >197608272325000 197608272334120 >197608272350360 197608272352420 >197608272358480 197608280100300 >197608280106480 197608281017300 >197608281323480 197609010238300 >197609010244120 197609010244120 >197609010251300 197609022329120 >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >Magnetics Data (l-6-76-ar.220_011) >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >197608271952300 197608272003200 >197608272009500 197608272320530 >197608272330010 197608272339300 >197608272355390 197608272357400 >197608280003500 197608280105500 >197608280111480 197608281023100 >197608281328500 197609010243500 >197609010249100 197609010249100 >197609010256300 197609010641200 >197609010646400 197609030012380 >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >Bathymetry Data (l-6-76-ar.335_011) >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >197608272300000 197608280128480 >197608280134420 197608280134420 >197608280141180 197608280141180 >197608280147000 197608280147000 >197608280221540 197608280233540 >197608280239000 197608280316420 >197608280322000 197608280414420 >197608280420240 197608280420240 >197608280428480 197608280503300 >197608280508540 197608280508540 >197608280514120 197608280514120 >197608280519360 197608280523360 >197608280529420 197608280706420 >197608281413060 197608281533480 >197608281556000 197608281713540 >197608281720120 197608281734540 >197608281740060 197608281925540 >197608281935180 197608281939120 >197608281944360 197608281945540 >197608281951180 197608282035540 >197608282041360 197608282049060 >197608282054540 197608282151420 >197608282156480 197608282245540 >197608282251240 197608282302540 >197608282308360 197608282308360 >197608282313480 197608282313480 >197608282319540 197608282319540 >197608282325360 197608282334540 >197608282343000 197608282343000 >197608282348240 197608282348240 >197608282353360 197608290015240 >197608290020540 197608290020540 >197608290026360 197608290100360 >197608290106060 197608290114420 >197608290122360 197608290129540 >197608290135540 197608290135540 >197608290142000 197608290206540 >197608290215420 197608290220000 >197608290228540 197608290319240 >197608290326480 197608290329360 >197608290600240 197608290714420 >197608290749120 197608290800540 >197608290855120 197608290914480 >197608290928300 197608290945540 >197608290951120 197608290951120 >197608290956240 197608291005360 >197608291010480 197608291045480 >197608291051420 197608291051420 >197608291057420 197608291101180 >197608291106420 197608291117420 >197608291122480 197608291122480 >197608291127540 197608291201120 >197608291206240 197608291231120 >197608291237120 197608291237120 >197608291243300 197608291246240 >197608291251420 197608291331060 >197608291337240 197608291337240 >197608291342360 197608291412420 >197608291417540 197608291454240 >197608291526240 197608291534180 >197608291540300 197608291615420 >197608291621300 197608291821540 >197608291900240 197608292214060 >197608292233300 197608292328540 >197608292342120 197608300036540 >197608300045240 197608300100000 >197608300115540 197608300445300 >197608300501300 197608300529420 >197608300535240 197608300554360 >197608300600000 197608300600000 >197608300618240 197608301049420 >197608301102240 197608301142540 >197608301148000 197608301357300 >197608301416480 197608301533180 >197608301546360 197608301648300 >197608301701540 197608301816240 >197608301821480 197608301933000 >197608301939120 197608302002480 >197608302017060 197608302040360 >197608302046180 197608302054000 >197608302100000 197608302301540 >197608302309300 197608310022360 >197608310136540 197608310319360 >197608310325120 197608310406540 >197608310715240 197608310758360 >197608310851540 197608311033540 >197608311046300 197608311133000 >197608311144420 197608311219240 >197608311225000 197608311324000 >197608311329300 197608311415240 >197608311420300 197608311430000 >197608311709000 197608311801420 >197608311806480 197608311806480 >197608311812060 197608311812060 >197608311818540 197608311827540 >197608311833120 197608311924180 >197608311930000 197608312008420 >197608312015000 197608312119240 >197608312247000 197609010206000 >197609010802060 197609010802060 >197609010809000 197609010817540 >197609010823000 197609010827060 >197609010832120 197609010836360 >197609010842000 197609010842000 >197609010847240 197609010942420 >197609010947480 197609011026000 >197609011031420 197609011129000 >197609011148240 197609011314060 >197609011320240 197609011405540 >197609011411300 197609011415120 >197609011420540 197609011432000 >197609011437060 197609011501060 >197609011508000 197609011551540 >197609011557180 197609011557180 >197609011602240 197609011703480 >197609011709120 197609011905060 >197609011916120 197609012043180 >197609012049000 197609012241120 >197609012247060 197609020543120 >YYYYMMDDHHMMSST YYYYMMDDHHMMSST Positional_Accuracy: Horizontal_Positional_Accuracy: Horizontal_Positional_Accuracy_Report: Unspecified Vertical_Positional_Accuracy: Vertical_Positional_Accuracy_Report: Unspecified Lineage: Process_Step: Process_Description: Navigation Data >Converted to time format with year at start. > >01/31/86 KAYE DUA0:[DATA.L676AR.N]L676AR.011; >DRB0:[DRS.REFMT]REFORMAT.EXE;5 > Process_Date: 19960119 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey (USGS) , Coastal and Marine Geology (CMG) Contact_Person: Carolyn H. Degnan Contact_Position: Geophysicist Contact_Address: Address_Type: mailing and physical address Address: USGS Pacific Coastal & Marine Science Center, 400 Natural Bridges Drive City: Santa Cruz State_or_Province: CA Postal_Code: 95060-5792 Country: USA Contact_Voice_Telephone: (831) 460-7452 Contact_Facsimile_Telephone: (831) 427-4748 Contact_Electronic_Mail_Address: infobank@octopus.wr.usgs.gov Process_Step: Process_Description: Gravity Data >10/31/1998 /tiger/l/l676ar/grav/l-6-76-ar.161_011 >/bear/programs/edit/automerge/automerge > >Input was... >Converted to time format with year at start. > >01/02/86 BARB DUA0:[DATA.L676AR.G]L676AR.161; >DRB0:[DRS.REFMT]REFORMAT.EXE;5 > >Input was... >Converted to time format with year at start. > >01/31/86 KAYE DUA0:[DATA.L676AR.N]L676AR.011; >DRB0:[DRS.REFMT]REFORMAT.EXE;5 > >time, lat, long, time(sec) to nearest nav fix, data values Process_Date: 19981031 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey (USGS) , Coastal and Marine Geology (CMG) Contact_Person: Carolyn H. Degnan Contact_Position: Geophysicist Contact_Address: Address_Type: mailing and physical address Address: USGS Pacific Coastal & Marine Science Center, 400 Natural Bridges Drive City: Santa Cruz State_or_Province: CA Postal_Code: 95060-5792 Country: USA Contact_Voice_Telephone: (831) 460-7452 Contact_Facsimile_Telephone: (831) 427-4748 Contact_Electronic_Mail_Address: infobank@octopus.wr.usgs.gov Process_Step: Process_Description: Magnetics Data >06/20/2012 carolyn l-6-76-ar.220_011 > >Reprocessed using subroutines from Susan Macmillan's >IGRF SYNTHESIS PROGRAM http://www.ngdc.noaa.gov/IAGA/vmod/igrf11.f >with IGRF-11 coeffiecients integrated into the source code. >/infobank/programs/mag/magred11/magred11.for >Using geodetic coordinate system (Earth shape approximated by spheriod) >with altitude 0.0 km (for sea level). > >Input was... >10/31/1998 /tiger/l/l676ar/mag/l-6-76-ar.200_011 >/bear/programs/edit/automerge/automerge > >Converted to time format with year at start. > >05/15/86 CAROLYN DRS$DATA:[LEE76]L676AR.200; >DRB0:[DRS.REFMT]REFORMAT.EXE;5 >was L676AR.200 from Barb (slaves were unreadable after 241/2329) > >Converted to time format with year at start. > >01/31/86 KAYE DUA0:[DATA.L676AR.N]L676AR.011; >DRB0:[DRS.REFMT]REFORMAT.EXE;5 > >time, lat, long, time(sec) to nearest nav fix, data values Process_Date: 20120620 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey (USGS) , Coastal and Marine Geology (CMG) Contact_Person: Carolyn H. Degnan Contact_Position: Geophysicist Contact_Address: Address_Type: mailing and physical address Address: USGS Pacific Coastal & Marine Science Center, 400 Natural Bridges Drive City: Santa Cruz State_or_Province: CA Postal_Code: 95060-5792 Country: USA Contact_Voice_Telephone: (831) 460-7452 Contact_Facsimile_Telephone: (831) 427-4748 Contact_Electronic_Mail_Address: infobank@octopus.wr.usgs.gov Process_Step: Process_Description: Bathymetry Data >11/03/2008 jpaz /infobank/l/l676ar/bath/l-6-76-ar.335_011 >/infobank/programs/edit/automerge/automerge > >Input was... >Converted to time format with year at start. > >02/11/86 BECKIE DISK$USERDISK:[BECKIE.TEMP]L676AR.335; >DRB0:[DRS.BAT]BATRED.EXE;1 >This file was hand-digetized in 2-way traveltime(secs). >It was reduced using no Matthews correction and velocity >of sound assumed was 1500m/sec. > >Input was... >Converted to time format with year at start. > >01/31/86 KAYE DUA0:[DATA.L676AR.N]L676AR.011; >DRB0:[DRS.REFMT]REFORMAT.EXE;5 > >time, lat, long, time(sec) to nearest nav fix, data values Process_Date: 20081103 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey (USGS) , Coastal and Marine Geology (CMG) Contact_Person: Carolyn H. Degnan Contact_Position: Geophysicist Contact_Address: Address_Type: mailing and physical address Address: USGS Pacific Coastal & Marine Science Center, 400 Natural Bridges Drive City: Santa Cruz State_or_Province: CA Postal_Code: 95060-5792 Country: USA Contact_Voice_Telephone: (831) 460-7452 Contact_Facsimile_Telephone: (831) 427-4748 Contact_Electronic_Mail_Address: infobank@octopus.wr.usgs.gov Process_Step: Process_Description: MGD77 file creation - The available data for each cruise leg are re-formatted and combined into the Marine Geophysical Data Exchange Format (MGD77) and into the internal NGDC SEIS-NAV format by USGS using several USGS developed FORTRAN programs.The FORTRAN programs sample the navigation to every integer minute of the cruise. When necessary, the latitudes and longitudes are linearly interpolated. If the time between the actual navigation fixes exceeds five minutes, no data are included in the MGD77 file.To build the MGD77 file, gravity, magnetics, and bathymetry are added to this sampled navigation. When necessary, gravity, magnetics, and bathymetry data are linearly interpolated if the time between the actual data samples does not exceed five minutes. If a time gap exceeds this, the data are not reported.The navigation data are merged with the seismic shot point data in a SEIS- NAV format file. For this file, navigation data are interpolated for each shot point. Both types of files are written to magnetic tape and sent to NGDC. Process_Date: 20120620 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey (USGS), Coastal and Marine Geology (CMG) Contact_Person: Carolyn H. Degnan Contact_Position: Geophysicist Contact_Address: Address_Type: mailing and physical address Address: USGS Pacific Coastal & Marine Science Center, 400 Natural Bridges Drive City: Santa Cruz State_or_Province: CA Postal_Code: 95060-5792 Country: USA Contact_Voice_Telephone: (831) 460-7452 Contact_Facsimile_Telephone: (831) 427-4748 Contact_Electronic_Mail_Address: infobank@octopus.wr.usgs.gov Process_Step: Process_Description: Keywords section of metadata optimized for discovery in USGS Coastal and Marine Geology Data Catalog. Process_Date: 20170201 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Person: Alan O. Allwardt Contact_Position: Contractor -- Information Specialist Contact_Address: Address_Type: mailing and physical address Address: 2885 Mission Street City: Santa Cruz State_or_Province: CA Postal_Code: 95060 Contact_Voice_Telephone: 831-460-7551 Contact_Facsimile_Telephone: 831-427-4748 Contact_Electronic_Mail_Address: aallwardt@usgs.gov Process_Step: Process_Description: Edited metadata to add keywords section with USGS persistent identifier as theme keyword. No data were changed. Process_Date: 20201019 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 Spatial_Data_Organization_Information: Indirect_Spatial_Reference: Arctic Direct_Spatial_Reference_Method: Point Point_and_Vector_Object_Information: SDTS_Terms_Description: SDTS_Point_and_Vector_Object_Type: Point Spatial_Reference_Information: Horizontal_Coordinate_System_Definition: Geographic: Latitude_Resolution: 0.000001 Longitude_Resolution: 0.000001 Geographic_Coordinate_Units: Decimal degrees Geodetic_Model: Horizontal_Datum_Name: D_WGS_1984 Ellipsoid_Name: WGS_1984 Semi-major_Axis: 6378137.000000 Denominator_of_Flattening_Ratio: 298.25722210100002 Entity_and_Attribute_Information: Detailed_Description: Entity_Type: Entity_Type_Label: l676ar.m77t Entity_Type_Definition: MGD77T single-beam bathymetry, gravity, and magnetics data file for L676AR Entity_Type_Definition_Source: NOAA's National Geophysical Data Center, See Hittelman and others (2010) Cross_Reference section above for details about the MGD77T format and citation information. Attribute: Attribute_Label: SURVEY_ID Attribute_Definition: Survey identifier supplied by the contributing organization Attribute_Definition_Source: NGDC Attribute_Domain_Values: Unrepresentable_Domain: This identifier varies in format and is supplied by the contributing organization Attribute: Attribute_Label: TIMEZONE Attribute_Definition: Time-zone correction Attribute_Definition_Source: NGDC Attribute_Domain_Values: Unrepresentable_Domain: In our datasets, no correction was applied. All values equal 0. Attribute: Attribute_Label: DATE Attribute_Definition: YYYYMMDD Attribute_Definition_Source: NGDC Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 19760827 Range_Domain_Maximum: 19760903 Attribute_Units_of_Measure: Year, month, day Attribute: Attribute_Label: TIME Attribute_Definition: Time Attribute_Definition_Source: NGDC Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0 Range_Domain_Maximum: 2359 Attribute_Units_of_Measure: hours and decimal minutes Attribute: Attribute_Label: LAT Attribute_Definition: Latitude Attribute_Definition_Source: World Geodetic System 1984 Geographic Coordinate System Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 64.48155 Range_Domain_Maximum: 67.51448 Attribute_Units_of_Measure: decimal degrees Attribute: Attribute_Label: LON Attribute_Definition: Longitude Attribute_Definition_Source: World Geodetic System 1984 Geographic Coordinate System Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -168.31173 Range_Domain_Maximum: -165.40790 Attribute_Units_of_Measure: decimal degrees Attribute: Attribute_Label: POS_TYPE Attribute_Definition: Indicates how lat/lon was obtained Attribute_Definition_Source: NGDC Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: 3 Attribute_Units_of_Measure: 1 = observed fix, 3 = interpolated fix, nil = unspecified Attribute: Attribute_Label: BAT_TTIME Attribute_Definition: Bathymetry, 2-way travel time Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 0.014 Range_Domain_Maximum: 0.075 Attribute_Units_of_Measure: seconds Attribute: Attribute_Label: CORR_DEPTH Attribute_Definition: Bathymetry, corrected depth Attribute_Definition_Source: U.S. Geological Survey Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 10.5 Range_Domain_Maximum: 56.3 Attribute_Units_of_Measure: decimal meters Attribute: Attribute_Label: BAT_CPCO Attribute_Definition: Bathymetric Correction code - details the procedure used for determining the sound velocity correction to depth Attribute_Definition_Source: NGDC Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 63 Range_Domain_Maximum: 63 Attribute_Units_of_Measure: 01-55 Matthews' Zones with zone , 59 Matthews' Zones, no zone specified, 60 S. Kuwahara Formula, 61 Wilson Formula, 62 Del Grosso Formula, 63 Carter's Tables, 88 Other (see Add. Doc.), 97 Computed using 1500 meters/sec, 98 Unknown if Corrected, 99 Unspecified Attribute: Attribute_Label: BAT_TYPCO Attribute_Definition: Bathymetry type code - indicates how the bathymetric value was obtained Attribute_Definition_Source: NGDC Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 1 Range_Domain_Maximum: 3 Attribute_Units_of_Measure: 1 - Observed, 3 - Interpolated (Header Seq. 12), 9 - Unspecified Attribute: Attribute_Label: MAG_TOT Attribute_Definition: Magnetics total field - 1st sensor Attribute_Definition_Source: NGDC Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 52147 Range_Domain_Maximum: 58859 Attribute_Units_of_Measure: gammas Attribute: Attribute_Label: MAG_RES Attribute_Definition: Magnetics residual field field Attribute_Definition_Source: NGDC Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -3708.1 Range_Domain_Maximum: 3756.8 Attribute_Units_of_Measure: gammas Attribute: Attribute_Label: GRA_OBS Attribute_Definition: Observed gravity Attribute_Definition_Source: NGDC Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 982232.7 Range_Domain_Maximum: 982451.9 Attribute_Units_of_Measure: milligals Attribute: Attribute_Label: EOTVOS Attribute_Definition: EOTVOS correction - E = 7.5 V cos(phi) * sin(alpha) + 0.0042 V*V Attribute_Definition_Source: NGDC Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -27 Range_Domain_Maximum: 33.4 Attribute_Units_of_Measure: milligals Attribute: Attribute_Label: FREEAIR Attribute_Definition: Free-air Anomaly = G(observed) minus G(theoretical) Attribute_Definition_Source: NGDC Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: -11.1 Range_Domain_Maximum: 2 Attribute_Units_of_Measure: milligals Overview_Description: Entity_and_Attribute_Overview: Bathymetry, gravity, magnetic, and navigation data for U.S. Geological Survey bathymetry survey L676AR in MGD77T format. Entity_and_Attribute_Detail_Citation: Attributes are obtained from MGD77T data files created from the navigation gravity, magnetic, and bathymetry best files. MGD77T is the standard, defined data format used for geophysical data in the National Geophysical Data Center. See Cross_Reference section above for citation details. Distribution_Information: Distributor: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey Contact_Address: Address_Type: mailing and physical address Address: 345 Middlefield Road MS 999 City: Menlo Park State_or_Province: CA Postal_Code: 94025 Country: USA Contact_Voice_Telephone: (650) 329-5078 Contact_Facsimile_Telephone: (650) 329-5190 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: MGD77t Format_Version_Number: 10 Format_Specification: MGD77 Format_Information_Content: tab-delimited ASCII text files. Transfer_Size: .789 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://www.ngdc.noaa.gov/mgg/trk/trackline/samuel_p._lee/l676ar/mgd77/ Access_Instructions: Data are available for download on the World Wide Web (WWW). Fees: None Metadata_Reference_Information: Metadata_Date: 20201019 Metadata_Contact: Contact_Information: Contact_Person_Primary: Contact_Person: Gregory K. Miller Contact_Organization: U.S. Geological Survey Contact_Position: Physical Scientist Contact_Address: Address_Type: mailing and physical address Address: U.S. Geological Survey, 600 Fourth Street South City: St. Petersburg State_or_Province: FL Postal_Code: 33701 Country: USA Contact_Voice_Telephone: (727) 803-8747, ext. 3020 Contact_Electronic_Mail_Address: gmiller@usgs.gov Metadata_Standard_Name: FGDC Content Standards for Digital Geospatial Metadata Metadata_Standard_Version: FGDC-STD-001-1998