Metadata: Identification_Information: Citation: Citation_Information: Originator: U.S. Geological Survey Originator: Coastal and Marine Geology Program Publication_Date: 2013 Title: l3a81nc.m77t - MGD77 data file for Geophysical data from field activity L-3A-81-NC in Central Coast, Northern California from 04/16/1981 to 04/26/1981 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/l3a81nc/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-3A-81-NC in Central Coast, Northern California from 04/16/1981 to 04/26/1981, http://walrus.wr.usgs.gov/infobank/l/l3a81nc/html/l-3a-81-nc.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/l3a81nc/html/l-3a-81-nc.bath.html, http://walrus.wr.usgs.gov/infobank/l/l3a81nc/html/l-3a-81-nc.grav.html, and http://walrus.wr.usgs.gov/infobank/l/l3a81nc/html/l-3a-81-nc.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: 19810416 Ending_Date: 19810426 Currentness_Reference: ground condition Status: Progress: Complete Maintenance_and_Update_Frequency: None planned Spatial_Domain: Bounding_Coordinates: West_Bounding_Coordinate: -122.64710 East_Bounding_Coordinate: -119.20955 North_Bounding_Coordinate: 37.81914 South_Bounding_Coordinate: 34.08567 Keywords: Theme: Theme_Keyword_Thesaurus: USGS Metadata Identifier Theme_Keyword: USGS:85fe3b45-3eb1-44cf-bef4-860ad704c5d0 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: CA Place_Keyword: Central California EEZ Place_Keyword: Central Coast, Northern California Place_Keyword: North Pacific Ocean Place_Keyword: Northern California Place_Keyword: Northern Pacific Ocean Place_Keyword: USA 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: Dave McCulloch (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-3a-81-nc.070) >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >198104161750000 198104181441000 >198104181459000 198104181525000 >198104181534000 198104240721000 >198104240737000 198104261705000 >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >Gravity Data (l-3a-81-nc.152_070) >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >198104161900180 198104170014180 >198104170225180 198104170625180 >198104170640420 198104170836420 >198104170847420 198104171729420 >198104171740420 198104171832420 >198104171848420 198104180300420 >198104180315420 198104180720480 >198104181250180 198104181932420 >198104181939360 198104182011360 >198104182024360 198104182040360 >198104182051360 198104190227360 >198104190233180 198104190437540 >198104190446540 198104190507000 >198104190517000 198104190525000 >198104190602300 198104191328360 >198104191421360 198104191759240 >198104191808060 198104192215060 >198104192249300 198104200607480 >198104200626420 198104200646540 >198104200653000 198104200830240 >198104200837000 198104201453420 >198104201504420 198104201520420 >198104201529480 198104201824300 >198104201848480 198104202241120 >198104202321120 198104210659240 >198104210707240 198104210741240 >198104210751240 198104210809300 >198104210821300 198104211427360 >198104211446540 198104211549000 >198104211607000 198104211621000 >198104211631000 198104220058120 >198104220115120 198104220159180 >198104220221180 198104220249180 >198104220302360 198104220534480 >198104220542300 198104221029240 >198104221101240 198104221327540 >198104221336120 198104221915480 >198104221951480 198104222028000 >198104222039180 198104222045180 >198104222050300 198104230406480 >198104230420480 198104230436480 >198104230441540 198104230449540 >198104230504120 198104231005240 >198104231021240 198104231055300 >198104231111300 198104231223480 >198104231239480 198104231257540 >198104231335060 198104232029360 >198104232037360 198104240441240 >198104240517000 198104241041300 >198104241046360 198104241141360 >198104241216360 198104241642240 >198104241713240 198104241825240 >198104241832060 198104250321180 >198104250346180 198104250558480 >198104250613480 198104251641240 >198104251647540 198104251742000 >198104251751000 198104251815000 >198104251825180 198104251920300 >198104260350300 198104260645180 >198104260657180 198104260837180 >198104260856180 198104261258180 >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >Magnetics Data (l-3a-81-nc.220_070) >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >198104171906400 198104180726430 >198104181242150 198104181939230 >198104181944350 198104190531100 >198104190607270 198104191804590 >198104191812030 198104200835350 >198104200841030 198104201830020 >198104201852500 198104210705580 >198104210712260 198104211433180 >198104211450540 198104220539580 >198104220546300 198104221334220 >198104221341100 198104231229340 >198104231243500 198104241831580 >198104241837060 198104251821300 >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >Bathymetry Data (l-3a-81-nc.301_070) >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >198104170639400 198104180725470 >198104181242150 198104181937390 >198104181944350 198104182018350 >198104182032350 198104190529230 >198104190607270 198104191803030 >198104191812030 198104200834230 >198104200841030 198104201828270 >198104201852500 198104202249100 >198104202301100 198104210705020 >198104210712260 198104211433140 >198104211450540 198104211600580 >198104211607580 198104211607580 >198104211613580 198104220539060 >198104220546300 198104221333140 >198104221341100 198104222049180 >198104222054300 198104230441300 >198104230446540 198104231228460 >198104231243500 198104241830260 >198104241837060 198104251646060 >198104251652540 198104251714540 >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. > >05/09/85 KAYE USR$DISK:[KAYE.COASTAL]NEW.070; >USR$DISK:[DRS.REFMT]REFORMAT.EXE;4 >Original filename is l381nc.sinsd1._ from VAM339 > 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/l3a81nc/grav/l-3a-81-nc.152_070 >/bear/programs/edit/automerge/automerge > >Input was... >Converted to time format with year at start. > >10/11/85 BARB DRS$DATA:[L381NC.G]L381NC.152; >DRB0:[DRS.REFMT]REFORMAT.EXE;4 > >Input was... >Converted to time format with year at start. > >05/09/85 KAYE USR$DISK:[KAYE.COASTAL]NEW.070; >USR$DISK:[DRS.REFMT]REFORMAT.EXE;4 >Original filename is l381nc.sinsd1._ from VAM339 > >time, lat, long, time(sec) to nearest nav fix, data values Process_Date: 19981031 Process_Contact: Contact_Information: Contact_Organization_Primary: Contact_Organization: U.S. Geological Survey (USGS) , Coastal and Marine Geology (CMG) Contact_Person: Carolyn H. Degnan Contact_Position: Geophysicist Contact_Address: Address_Type: mailing and physical address Address: USGS Pacific Coastal & Marine Science Center, 400 Natural Bridges Drive City: Santa Cruz State_or_Province: CA Postal_Code: 95060-5792 Country: USA Contact_Voice_Telephone: (831) 460-7452 Contact_Facsimile_Telephone: (831) 427-4748 Contact_Electronic_Mail_Address: infobank@octopus.wr.usgs.gov Process_Step: Process_Description: Magnetics Data >06/20/2012 carolyn l-3a-81-nc.220_070 > >Reprocessed using subroutines from Susan Macmillan's >IGRF SYNTHESIS PROGRAM http://www.ngdc.noaa.gov/IAGA/vmod/igrf11.f >with IGRF-11 coeffiecients integrated into the source code. >/infobank/programs/mag/magred11/magred11.for >Using geodetic coordinate system (Earth shape approximated by spheriod) >with altitude 0.0 km (for sea level). > >Input was... >10/31/1998 /tiger/l/l3a81nc/mag/l-3a-81-nc.200_070 >/bear/programs/edit/automerge/automerge > >Converted to time format with year at start. > >11/18/85 CAROLYN DRS$DATA:[L381NC.M]L381NC.200; >DRB0:[DRS.REFMT]REFORMAT.EXE;4 >was L381NC._.MAGSB1 on TAM262 >was L381NC220.DAT on VAM262 > >Converted to time format with year at start. > >05/09/85 KAYE USR$DISK:[KAYE.COASTAL]NEW.070; >USR$DISK:[DRS.REFMT]REFORMAT.EXE;4 >Original filename is l381nc.sinsd1._ from VAM339 > >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 >10/31/1998 /tiger/l/l3a81nc/bath/l-3a-81-nc.301_070 >/bear/programs/edit/automerge/automerge > >Input was... >Converted to time format with year at start. > >08/29/85 BECKIE DUA0:[DATA.L381NC.B]L381NC.301; >DRB0:[DRS.REFMT]REFORMAT.EXE;4 >This file is edited 2 min. digitrack bathy. > >Input was... >Converted to time format with year at start. > >05/09/85 KAYE USR$DISK:[KAYE.COASTAL]NEW.070; >USR$DISK:[DRS.REFMT]REFORMAT.EXE;4 >Original filename is l381nc.sinsd1._ from VAM339 > >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: 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: Central Coast, Northern California 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: l3a81nc.m77t Entity_Type_Definition: MGD77T single-beam bathymetry, gravity, and magnetics data file for L3A81NC 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: 19810416 Range_Domain_Maximum: 19810426 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: 34.08567 Range_Domain_Maximum: 37.81914 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: -122.64710 Range_Domain_Maximum: -119.20955 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: MAG_TOT Attribute_Definition: Magnetics total field - 1st sensor Attribute_Definition_Source: NGDC Attribute_Domain_Values: Range_Domain: Range_Domain_Minimum: 47488.5 Range_Domain_Maximum: 59535 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: --2668.1 Range_Domain_Maximum: 9798.5 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: 979668.2 Range_Domain_Maximum: 979967.7 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: -68.3 Range_Domain_Maximum: 40.9 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: -75.5 Range_Domain_Maximum: 37.3 Attribute_Units_of_Measure: milligals Overview_Description: Entity_and_Attribute_Overview: Bathymetry, gravity, magnetic, and navigation data for U.S. Geological Survey bathymetry survey L3A81NC 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: 1.1 Digital_Transfer_Option: Online_Option: Computer_Contact_Information: Network_Address: Network_Resource_Name: http://www.ngdc.noaa.gov/mgg/trk/trackline/samuel_p._lee/l3a81nc/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