l284an.m77t - MGD77 data file for Geophysical data from field activity L-2-84-AN in Antarctica from 02/03/1984 to 03/03/1984

Frequently anticipated questions:

• What does this data set describe?
  1. How might this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
• Who produced the data set?
  1. Who are the originators of the data set?
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
• Why was the data set created?
• How was the data set created?
  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
  3. What similar or related data should the user be aware of?
• How reliable are the data; what problems remain in the data set?
  1. How well have the observations been checked?
  2. How accurate are the geographic locations?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
  5. How consistent are the relationships among the data, including topology?
• How can someone get a copy of the data set?
  1. Are there legal restrictions on access or use of the data?
  2. Who distributes the data?
  3. What's the catalog number I need to order this data set?
  4. What legal disclaimers am I supposed to read?
  5. How can I download or order the data?
• Who wrote the metadata?

What does this data set describe?

1. How might this data set be cited?
   U.S. Geological Survey, and Coastal and Marine Geology Program, 2013, l284an.m77t - MGD77 data file for Geophysical data from field activity L-2-84-AN in Antarctica from 02/03/1984 to 03/03/1984: U.S. Geological Survey, Menlo Park, CA.

   Online Links:

   • http://www.ngdc.noaa.gov/mgg/trk/trackline/samuel_p._lee/l284an/mgd77/

   This is part of the following larger work.
   Steele, Wm. Clinton, Degnan, Carolyn H., Deeter, Gary B., and Riordan, Jean A., 1980, DESCRIPTION OF MARINE GEOPHYSICAL DATA COLLECTED BY THE U.S. GEOLOGICAL SURVEY AND HOW TO OBTAIN IT: U.S. Geological Survey Open File Report 167, U.S. Geological Survey, Menlo Park, CA.

   Online Links:

   • http://pubs.usgs.gov/of/1989/0167/report.pdf

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: 163.00166
   East_Bounding_Coordinate: -173.37114
   North_Bounding_Coordinate: -43.59192
   South_Bounding_Coordinate: -77.64513
   

3. What does it look like?
4. Does the data set describe conditions during a particular time period?

   Beginning_Date: 03-Feb-1984

   Ending_Date: 03-Mar-1984

   Currentness_Reference:

   ground condition

5. What is the general form of this data set?

   Geospatial_Data_Presentation_Form: tab-delimited ASCII text files
   

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?
      

      Indirect_Spatial_Reference: Antarctica
      

      This is a Point data set. It contains the following vector data types (SDTS terminology):
      • Point
   2. What coordinate system is used to represent geographic features?
      Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.000001. Longitudes are given to the nearest 0.000001. Latitude and longitude values are specified in Decimal degrees. The horizontal datum used is D_WGS_1984.
      The ellipsoid used is WGS_1984.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.25722210100002.
      
7. How does the data set describe geographic features?

   l284an.m77t

   MGD77Tsingle-beam bathymetry, gravity, and magnetics data file for L284AN (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.)

   SURVEY_ID

   Survey identifier supplied by the contributing organization (Source: NGDC) This identifier varies in format and is supplied by the contributing organization

   TIMEZONE

   Time-zone correction (Source: NGDC) In our datasets, no correction was applied. All values equal 0.

   DATE

   YYYYMMDD (Source: NGDC)

   Range of values
   Minimum:	19840203
   Maximum:	19840303
   Units:	Year, month, day

   TIME

   Time (Source: NGDC)

   Range of values
   Minimum:	0
   Maximum:	2359.75
   Units:	hours and decimal minutes

   LAT

   Latitude (Source: World Geodetic System 1984 Geographic Coordinate System)

   Range of values
   Minimum:	-77.64512
   Maximum:	-43.59192
   Units:	decimal degrees

   LON

   Longitude (Source: World Geodetic System 1984 Geographic Coordinate System)

   Range of values
   Minimum:	-173.37114
   Maximum:	179.99866
   Units:	decimal degrees

   POS_TYPE

   Indicates how lat/lon was obtained (Source: NGDC)

   Range of values
   Minimum:	1
   Maximum:	3
   Units:	1 = observed fix, 3 = interpolated fix, nil = unspecified

   BAT_TTIME

   Bathymetry, 2-way travel time (Source: U.S. Geological Survey)

   Range of values
   Minimum:	0.067
   Maximum:	4.51
   Units:	seconds

   CORR_DEPTH

   Bathymetry, corrected depth (Source: U.S. Geological Survey)

   Range of values
   Minimum:	50.3
   Maximum:	3336.5
   Units:	decimal meters

   BAT_CPCO

   Bathymetric Correction code - details the procedure used for determining the sound velocity correction to depth (Source: NGDC)

   Range of values
   Minimum:	63
   Maximum:	63
   Units:	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

   BAT_TYPCO

   Bathymetry type code - indicates how the bathymetric value was obtained (Source: NGDC)

   Range of values
   Minimum:	1
   Maximum:	3
   Units:	1 - Observed, 3 - Interpolated (Header Seq. 12), 9 - Unspecified

   MAG_TOT

   Magnetics total field - 1st sensor (Source: NGDC)

   Range of values
   Minimum:	63859.5
   Maximum:	66431.6
   Units:	gammas

   MAG_TOT2

   Magnetics total field - 2nd sensor (Source: NGDC)

   Range of values
   Minimum:	63929
   Maximum:	66425.9
   Units:	gammas

   MAG_RES

   Magnetics residual field field (Source: NGDC)

   Range of values
   Minimum:	-655.2
   Maximum:	719.7
   Units:	gammas

   MAG_RESSEN

   SENSOR FOR RESIDUAL FIELD (Source: NGDC)

   Range of values
   Minimum:	1
   Maximum:	1
   Units:	1 - first sensor, 2 - second sensor, 9 - Unspecified

   GRA_OBS

   Observed gravity (Source: NGDC)

   Range of values
   Minimum:	980558.9
   Maximum:	982989.5
   Units:	milligals

   EOTVOS

   EOTVOS correction - E = 7.5 V cos(phi) * sin(alpha) + 0.0042 V*V (Source: NGDC)

   Range of values
   Minimum:	-15
   Maximum:	20.4
   Units:	milligals

   FREEAIR

   Free-air Anomaly = G(observed) minus G(theoretical) (Source: NGDC)

   Range of values
   Minimum:	-89.8
   Maximum:	40.6
   Units:	milligals

   LINEID

   LINE/TRACK/SEGMENT ID (Source: NGDC)

   Range of values
   Minimum:	401
   Maximum:	419
   Units:	Used, for example, to cross reference with seismic data.

   POINTID

   SEISMIC SHOT-POINT NUMBER/POINT ID (Source: NGDC)

   Range of values
   Minimum:	41
   Maximum:	6359
   Units:	Used, for example, to cross reference with seismic data.

   Entity_and_Attribute_Overview:

   Bathymetry, gravity, magnetic, and navigation data for U.S. Geological Survey bathymetry survey L284AN 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.

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • U.S. Geological Survey
   • Coastal and Marine Geology Program
2. Who also contributed to the data set?

   Alan Cooper (Chief Scientist)

3. To whom should users address questions about the data?
   Gregory K. Miller

   U.S. Geological Survey

   Physical Scientist

   600 4th Street South

   St. Petersburg, FL
   

   USA

   (727) 803-8747, ext. 3020 (voice)

   gmiller@usgs.gov

Why was the data set created?

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/ ).

How was the data set created?

1. From what previous works were the data drawn?
2. How were the data generated, processed, and modified?

   Date: 19-Jan-1996 (process 1 of 7)

   Navigation Data >Converted to time format with year at start. > >10/16/86 CAROLYN DRS$DATA:[L284AN.TEST]L284ANEOT.070; >DUA0:[DRS.NAV]EOTCSSP.EXE; > >Input was... >10/16/86 CAROLYN DRS$DATA:[L284AN.TEST]L284ANMERG.070; >DUA0:[DRS.EDIT]MERGEIT.EXE;1 >removed and interpolated 180 degree longitude fix errors > >08/27/86 BECKIE DUA0:[DATA.L284AN]L284AN.070; >DRB0:[DRS.NAV]EOTCSSP.EXE; > >03/14/85 KAYE USR$DISK:[DRS.DATA.L2.N]NEW.055; >USR$DISK:[DRS.REFMT]REFORMAT.EXE;3 >Data has been run through sinsadj, naved and wpedit > >08/27/86 BECKIE DUA0:[DATA.L284AN]L284AN.070; >DRB0:[DRS.NAV]EOTCSSP.EXE; > >03/14/85 KAYE USR$DISK:[DRS.DATA.L2.N]NEW.055; >USR$DISK:[DRS.REFMT]REFORMAT.EXE;3 >Data has been run through sinsadj, naved and wpedit > Person who carried out this activity:
   

   U.S. Geological Survey (USGS) , Coastal and Marine Geology (CMG)

   Attn: Carolyn H. Degnan

   Geophysicist

   USGS Pacific Coastal & Marine Science Center, 400 Natural Bridges Drive

   Santa Cruz, CA
   

   USA

   (831) 460-7452 (voice)

   (831) 427-4748 (FAX)

   infobank@octopus.wr.usgs.gov

   Date: 31-Oct-1998 (process 2 of 7)

   Gravity Data >10/31/1998 /tiger/l/l284an/grav/l-2-84-an.163_070 >/bear/programs/edit/automerge/automerge > >Input was... >Converted to time format with year at start. > >07/07/86 CAROLYN DRS$DATA:[L284AN.NEWZELAND]L284AN.163; >DRB0:[DRS.EDIT]MERGEIT.EXE;1 >eotvos and faa were processed in New Zealand and re-merged >with obs_grv and theo_grv from L284AN.161 for these times: > 034/1013-043/0311 (from RS8401.DAT) > 047/0757-047/1129 (from RS84047.DAT) > 052/0900-054/0300 (from RS84052.DAT) > >The attached memo to Alan Cooper >from Fred Davey (telephone: 738 208) > Department of Scientific and Industrial Research > Geophysics Division > P.O. Box 1320, Wellington, New Zealand >dated 1 August 1986 states: > > Enclosed one magnetic tape with Day 047/0630-1200 and > Day 52/0900-54/0300. > > Data from 4/0100-49/0504 was in general bad, the section > noted above is the only bit I would consider using. > > Data from the start of line 416 is average to poor in quality, > especially with respect to base level shift. The relative > values along the line are probably accurate to about five > milligals, especially over the Iselin Bank, hence I used > the data for modelling. However as an accurate data set > for data bases I would only include them after further > checking with good quality cross lines. Hence they were > left out of the data tape I forwarded. > >03/14/85 BARB USR$DISK:[DRS.DATA.L2.G]L284AN.161; >USR$DISK:[DRS.REFMT]REFORMAT.EXE;3 >Meter 53 >Land Ties: 0340850000 968841.9 > 0630619000 968841.9 > >Input was... >Converted to time format with year at start. > >10/16/86 CAROLYN DRS$DATA:[L284AN.TEST]L284ANEOT.070; >DUA0:[DRS.NAV]EOTCSSP.EXE; > >10/16/86 CAROLYN DRS$DATA:[L284AN.TEST]L284ANMERG.070; >DUA0:[DRS.EDIT]MERGEIT.EXE;1 >removed and interpolated 180 degree longitude fix errors > >08/27/86 BECKIE DUA0:[DATA.L284AN]L284AN.070; >DRB0:[DRS.NAV]EOTCSSP.EXE; > >03/14/85 KAYE USR$DISK:[DRS.DATA.L2.N]NEW.055; >USR$DISK:[DRS.REFMT]REFORMAT.EXE;3 >Data has been run through sinsadj, naved and wpedit > >08/27/86 BECKIE DUA0:[DATA.L284AN]L284AN.070; >DRB0:[DRS.NAV]EOTCSSP.EXE; > >03/14/85 KAYE USR$DISK:[DRS.DATA.L2.N]NEW.055; >USR$DISK:[DRS.REFMT]REFORMAT.EXE;3 >Data has been run through sinsadj, naved and wpedit > >time, lat, long, time(sec) to nearest nav fix, data values Person who carried out this activity:
   

   U.S. Geological Survey (USGS) , Coastal and Marine Geology (CMG)

   Attn: Carolyn H. Degnan

   Geophysicist

   USGS Pacific Coastal & Marine Science Center, 400 Natural Bridges Drive

   Santa Cruz, CA
   

   USA

   (831) 460-7452 (voice)

   (831) 427-4748 (FAX)

   infobank@octopus.wr.usgs.gov

   Date: 21-Jun-2012 (process 3 of 7)

   Magnetics Data >06/21/2012 carolyn l-2-84-an.260_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/l284an/mag/l-2-84-an.240_070 >/bear/programs/edit/automerge/automerge > >Converted to time format with year at start. > >01/09/86 CAROLYN USR$DISK:[DRS.DATA.L284AN.M]L284AN.240; >034/1547-053/1640 was L24M01.201 >055/0728-056/2127 was L24M02.201 > >Converted to time format with year at start. > >10/16/86 CAROLYN DRS$DATA:[L284AN.TEST]L284ANEOT.070; >DUA0:[DRS.NAV]EOTCSSP.EXE; > >10/16/86 CAROLYN DRS$DATA:[L284AN.TEST]L284ANMERG.070; >DUA0:[DRS.EDIT]MERGEIT.EXE;1 >removed and interpolated 180 degree longitude fix errors > >08/27/86 BECKIE DUA0:[DATA.L284AN]L284AN.070; >DRB0:[DRS.NAV]EOTCSSP.EXE; > >03/14/85 KAYE USR$DISK:[DRS.DATA.L2.N]NEW.055; >USR$DISK:[DRS.REFMT]REFORMAT.EXE;3 >Data has been run through sinsadj, naved and wpedit > >08/27/86 BECKIE DUA0:[DATA.L284AN]L284AN.070; >DRB0:[DRS.NAV]EOTCSSP.EXE; > >03/14/85 KAYE USR$DISK:[DRS.DATA.L2.N]NEW.055; >USR$DISK:[DRS.REFMT]REFORMAT.EXE;3 >Data has been run through sinsadj, naved and wpedit > >time, lat, long, time(sec) to nearest nav fix, data values Person who carried out this activity:
   

   U.S. Geological Survey (USGS) , Coastal and Marine Geology (CMG)

   Attn: Carolyn H. Degnan

   Geophysicist

   USGS Pacific Coastal & Marine Science Center, 400 Natural Bridges Drive

   Santa Cruz, CA
   

   USA

   (831) 460-7452 (voice)

   (831) 427-4748 (FAX)

   infobank@octopus.wr.usgs.gov

   Date: 07-Feb-2002 (process 4 of 7)

   Bathymetry Data >02/07/2002 clint l-2-84-an.331_070 >/infobank/programs/edit/automerge/automerge > >Input was... >Converted to time format with year at start. > >03/27/85 BECKIE USR$DISK:[DRS.DATA.L284AN.B]L284AN.330; >DRA1:[DRS.REFMT]REFORMAT.EXE;3 >Hand-digetized edited bathy, depth calculated useing >1500M per second as travel time. > >Input was... >Converted to time format with year at start. > >10/16/86 CAROLYN DRS$DATA:[L284AN.TEST]L284ANEOT.070; >DUA0:[DRS.NAV]EOTCSSP.EXE; > >10/16/86 CAROLYN DRS$DATA:[L284AN.TEST]L284ANMERG.070; >DUA0:[DRS.EDIT]MERGEIT.EXE;1 >removed and interpolated 180 degree longitude fix errors > >08/27/86 BECKIE DUA0:[DATA.L284AN]L284AN.070; >DRB0:[DRS.NAV]EOTCSSP.EXE; > >03/14/85 KAYE USR$DISK:[DRS.DATA.L2.N]NEW.055; >USR$DISK:[DRS.REFMT]REFORMAT.EXE;3 >Data has been run through sinsadj, naved and wpedit > >08/27/86 BECKIE DUA0:[DATA.L284AN]L284AN.070; >DRB0:[DRS.NAV]EOTCSSP.EXE; > >03/14/85 KAYE USR$DISK:[DRS.DATA.L2.N]NEW.055; >USR$DISK:[DRS.REFMT]REFORMAT.EXE;3 >Data has been run through sinsadj, naved and wpedit > >time, lat, long, time(sec) to nearest nav fix, data values Person who carried out this activity:
   

   U.S. Geological Survey (USGS) , Coastal and Marine Geology (CMG)

   Attn: Carolyn H. Degnan

   Geophysicist

   USGS Pacific Coastal & Marine Science Center, 400 Natural Bridges Drive

   Santa Cruz, CA
   

   USA

   (831) 460-7452 (voice)

   (831) 427-4748 (FAX)

   infobank@octopus.wr.usgs.gov

   Date: 20-Jun-2012 (process 5 of 7)

   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. Person who carried out this activity:
   

   U.S. Geological Survey (USGS), Coastal and Marine Geology (CMG)

   Attn: Carolyn H. Degnan

   Geophysicist

   USGS Pacific Coastal & Marine Science Center, 400 Natural Bridges Drive

   Santa Cruz, CA
   

   USA

   (831) 460-7452 (voice)

   (831) 427-4748 (FAX)

   infobank@octopus.wr.usgs.gov

   Date: 01-Feb-2017 (process 6 of 7)

   Keywords section of metadata optimized for discovery in USGS Coastal and Marine Geology Data Catalog. Person who carried out this activity:
   

   U.S. Geological Survey

   Attn: Alan O. Allwardt

   Contractor -- Information Specialist

   2885 Mission Street

   Santa Cruz, CA
   

   831-460-7551 (voice)

   831-427-4748 (FAX)

   aallwardt@usgs.gov

   Date: 19-Oct-2020 (process 7 of 7)

   Edited metadata to add keywords section with USGS persistent identifier as theme keyword. No data were changed. Person who carried out this activity:
   

   U.S. Geological Survey

   Attn: VeeAnn A. Cross

   Marine Geologist

   384 Woods Hole Road

   Woods Hole, MA
   

   508-548-8700 x2251 (voice)

   508-457-2310 (FAX)

   vatnipp@usgs.gov

3. What similar or related data should the user be aware of?
   Hittelman, Allen M., Groman, Robert C., Haworth, Richard T., Holcombe, Troy L., McHendrie, Graig, Smith, Stuart M., and Metzger, Dan R., 2010, The marine geophysical data exchange format - MGD77 / MGD77T: National Geophysical Data Center, National Oceanic and Atmospheric Administration, Boulder, CO.

   Online Links:

   • http://www.ngdc.noaa.gov/mgg/dat/geodas/docs/mgd77.pdf

   Other_Citation_Details: 25 p.
   

How reliable are the data; what problems remain in the data set?

1. How well have the observations been checked?
   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.
2. How accurate are the geographic locations?
   Unspecified
3. How accurate are the heights or depths?
   Unspecified
4. Where are the gaps in the data? What is missing?
   Start and end date/times of data >Navigation Data (l-2-84-an.070) >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >198402030906000 198402140217430 >198402140308590 198402140308590 >198402140318280 198402240055000 >198402240339590 198402262119000 >198402262130000 198402262130000 >198402262145000 198402262145000 >198402262200000 198402262200000 >198402262215000 198402262215000 >198402262230000 198402262230000 >198402262245000 198402262245000 >198402262300000 198402262300000 >198402262315000 198402262315000 >198402262330000 198402262330000 >198402262345000 198402262345000 >198402270000000 198402270000000 >198402270015000 198402270015000 >198402270031000 198402270031000 >198402270045000 198402270045000 >198402270100000 198402270100000 >198402270115000 198402270115000 >198402270130000 198402270130000 >198402270145000 198402270145000 >198402270200000 198402270200000 >198402270215000 198402270215000 >198402270242000 198402270242000 >198402270300000 198402270300000 >198402270315000 198402270315000 >198402270330000 198402270330000 >198402270345000 198402270345000 >198402270400000 198402270400000 >198402270415000 198402270415000 >198402270430000 198402270430000 >198402270445000 198402270445000 >198402270500000 198402270500000 >198402270515000 198402270515000 >198402270530000 198402270530000 >198402270545000 198402270545000 >198402270600000 198402270600000 >198402270615000 198402270615000 >198402270630000 198402270630000 >198402270645000 198402270645000 >198402270700000 198402270700000 >198402270715000 198402270715000 >198402270730000 198402270730000 >198402270745000 198402270745000 >198402270800000 198402270800000 >198402270815000 198402270815000 >198402270830000 198402270830000 >198402270845000 198402270845000 >198402270900000 198402270900000 >198402270915000 198402270915000 >198402270930000 198402270930000 >198402270945000 198402270945000 >198402271000000 198402271000000 >198402271015000 198402271015000 >198402271030000 198402271030000 >198402271045000 198402271045000 >198402271100000 198402271100000 >198402271115000 198402271115000 >198402271130000 198402271130000 >198402271145000 198402271145000 >198402271200000 198402271200000 >198402271215000 198402271215000 >198402271230000 198402271230000 >198402271245000 198402271245000 >198402271300000 198402271300000 >198402271315000 198402271315000 >198402271330000 198402271330000 >198402271345000 198402271345000 >198402271400000 198402271400000 >198402271415000 198402271415000 >198402271430000 198402271430000 >198402271445000 198402271445000 >198402271500000 198402271500000 >198402271515000 198402271515000 >198402271530000 198402271530000 >198402271545000 198402271545000 >198402271600000 198402271600000 >198402271615000 198402271615000 >198402271630000 198402271630000 >198402271645000 198402271645000 >198402271700000 198402271700000 >198402271715000 198402271715000 >198402271730000 198402271730000 >198402271745000 198402271745000 >198402271800000 198402271800000 >198402271815000 198402271815000 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>198402210857000 198402211948000 >198402212030000 198402222303000 >198402222347000 198402230300000 >198403022310000 198403022357000 >198403030025000 198403030152000 >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >Magnetics Data (l-2-84-an.260_070) >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >198402031547590 198402042359450 >198402060144230 198402060704350 >198402061118420 198402111749470 >198402112207590 198402120849050 >198402121122260 198402132031110 >198402171747020 198402172049460 >198402180619010 198402190945010 >198402201721020 198402221640250 >198402240728580 198402252127270 >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >Bathymetry Data (l-2-84-an.331_070) >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >198402031249000 198402031446000 >198402031504180 198402040039060 >198402040054360 198402040955480 >198402041001180 198402041111240 >198402041116300 198402041131180 >198402041136240 198402041429540 >198402041443240 198402042212360 >198402042218240 198402050122540 >198402051336120 198402051642120 >198402051657000 198402052302000 >198402052310540 198402060701540 >198402061101480 198402061138120 >198402061144360 198402061356000 >198402061404120 198402061923000 >198402061928480 198402070610180 >198402070616000 198402070732420 >198402070738120 198402070748540 >198402070754360 198402071145060 >198402071231360 198402071458360 >198402071504300 198402071519000 >198402071524060 198402071533060 >198402071538240 198402071603240 >198402071611000 198402071616420 >198402071621540 198402071630000 >198402071636000 198402071653420 >198402071659060 198402071759420 >198402071804540 198402081245060 >198402081326360 198402081516240 >198402081521300 198402081627360 >198402081633420 198402081912540 >198402081921240 198402090231360 >198402090255480 198402091649540 >198402091655180 198402091740240 >198402091747300 198402091827420 >198402091834300 198402091837240 >198402091842300 198402100509420 >198402100526420 198402100743480 >198402100748540 198402100914540 >198402100920420 198402101056000 >198402101104420 198402101130120 >198402101135360 198402101302420 >198402101308000 198402101320240 >198402101325540 198402101442360 >198402101448540 198402101530420 >198402101537240 198402101859120 >198402101909120 198402110215300 >198402110221120 198402111459540 >198402111505300 198402120055540 >198402120102120 198402120113240 >198402120119180 198402120122420 >198402120128120 198402120131060 >198402120137300 198402120139540 >198402120146360 198402120150300 >198402120155480 198402120158180 >198402120203480 198402120222060 >198402120227480 198402120913240 >198402120929000 198402121030540 >198402121131060 198402121405480 >198402121411120 198402122122420 >198402122135120 198402130106420 >198402130112480 198402130138420 >198402130143540 198402131229000 >198402131234060 198402131319120 >198402131324360 198402131351300 >198402131357060 198402132336180 >198402132341300 198402140241180 >198402140247060 198402140247060 >198402140252240 198402140414360 >198402140420480 198402140423180 >198402140429300 198402140434000 >198402140439180 198402140442360 >198402140448540 198402140559060 >198402140604300 198402140716480 >198402140730300 198402140808060 >198402140813420 198402140828300 >198402140835000 198402140851300 >198402140858540 198402141016300 >198402141040420 198402141115180 >198402141120300 198402141530240 >198402141535540 198402142303360 >198402142308420 198402150044420 >198402150050120 198402150234180 >198402150241000 198402150330000 >198402150907360 198402151208060 >198402151214360 198402151335120 >198402151340420 198402151507000 >198402151519420 198402152001480 >198402152007480 198402152035120 >198402152041000 198402152056060 >198402152101120 198402152119120 >198402152125480 198402152148540 >198402152154000 198402152205540 >198402152213360 198402152216060 >198402152222180 198402152309180 >198402152316120 198402160014060 >198402160019180 198402160046420 >198402160052240 198402160213120 >198402160309420 198402160449360 >198402160454540 198402160501360 >198402160507060 198402160603240 >198402160610480 198402160739360 >198402160745060 198402160918180 >198402160923540 198402160926120 >198402160931300 198402160931300 >198402160937180 198402161002540 >198402161008300 198402161023360 >198402161029360 198402161048240 >198402161054180 198402161056360 >198402161101480 198402161112420 >198402161118000 198402161132000 >198402161137180 198402161213480 >198402161219120 198402161225540 >198402161233240 198402161233240 >198402161238360 198402161242000 >198402161247060 198402161247060 >198402161255000 198402161259300 >198402161304540 198402161304540 >198402161312180 198402161414300 >198402161419360 198402161427480 >198402161819420 198402161907000 >198402161912420 198402161918300 >198402161925180 198402161927420 >198402161933300 198402161943360 >198402161949060 198402161951420 >198402161957360 198402161957360 >198402162003180 198402162019240 >198402162032420 198402162040120 >198402162047060 198402162051000 >198402162057000 198402162103180 >198402162111420 198402162114300 >198402162121420 198402162128360 >198402162137120 198402162137120 >198402162142300 198402162232240 >198402162237300 198402162250420 >198402162256060 198402162311240 >198402170012000 198402170151000 >198402170200060 198402170620420 >198402170626480 198402171004180 >198402171537540 198402172016540 >198402172027480 198402172049060 >198402172059240 198402172252420 >198402172258000 198402172312540 >198402180510180 198402181447000 >198402181452540 198402181536540 >198402181542120 198402181607060 >198402181612120 198402181636540 >198402181642360 198402181703240 >198402181709060 198402181737420 >198402181742540 198402181759300 >198402181807480 198402181818420 >198402181825180 198402181828180 >198402181836480 198402181842360 >198402181849060 198402181912180 >198402181917240 198402181934480 >198402181940480 198402182114180 >198402182120180 198402182137000 >198402182142060 198402182142060 >198402182150360 198402182234240 >198402182241120 198402182301420 >198402182309300 198402182325180 >198402182331300 198402190034180 >198402190041120 198402190058060 >198402190106060 198402190131420 >198402190137420 198402190147180 >198402190154060 198402190206000 >198402190212060 198402190231060 >198402190236360 198402190309540 >198402190315120 198402190318480 >198402190324060 198402190440420 >198402190446240 198402190500060 >198402190505480 198402190505480 >198402190511300 198402190514120 >198402190519360 198402190522240 >198402190530300 198402190534180 >198402190541180 198402190602180 >198402190607540 198402190655060 >198402190709180 198402190840180 >198402190845300 198402190852360 >198402190857480 198402190918480 >198402191424300 198402191817000 >198402191822180 198402191843060 >198402191848360 198402191945060 >198402191951060 198402192033420 >198402192038480 198402192141420 >198402192148240 198402192200000 >198402192206420 198402192244000 >198402192249420 198402192257480 >198402192302540 198402192309240 >198402192314360 198402192320420 >198402192325540 198402192328000 >198402192335360 198402200002540 >198402200008180 198402200010360 >198402200016000 198402200023360 >198402200030000 198402200030000 >198402200035540 198402200147300 >198402201531180 198402201858240 >198402201908180 198402202044000 >198402202054480 198402210244180 >198402210253360 198402210532480 >198402210551420 198402211233480 >198402211245180 198402211316360 >198402211323180 198402212014180 >198402212042420 198402221202120 >198402221208000 198402230457540 >198402230527060 198402230600000 >198402230608480 198402231331060 >198402231339420 198402231654180 >198402231700060 198402231847360 >198402231853240 198402232137420 >198402232144540 198402232333420 >198402232338540 198402240043240 >198402240749000 198402241616420 >198402241621480 198402241812120 >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >Seismic Shots Data (l-2-84-an.422_070) >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >198402031605200 198402032336200 >198402040005160 198402040108300 >198402040204280 198402040411070 >198402040422170 198402041215560 >198402041242070 198402042212310 >198402042315050 198402042351290 >198402061055190 198402061138240 >198402061153200 198402061300210 >198402061306530 198402070320090 >198402070400130 198402080108440 >198402080116330 198402080126190 >198402080211300 198402082121390 >198402082209240 198402092218140 >198402092300030 198402101604530 >198402101650180 198402101944520 >198402102003270 198402102229330 >198402102249230 198402110738550 >198402110821230 198402111505040 >198402111539580 198402120852290 >198402121246270 198402132024130 >198402201530050 198402210815120 >198402210855320 198402211952160 >198402212040460 198402221118220 >198402221200040 198402221611560 >198402222330160 198402230457040 >YYYYMMDDHHMMSST YYYYMMDDHHMMSST
5. How consistent are the relationships among the observations, including topology?
   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.

How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

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.

1. Who distributes the data set? (Distributor 1 of 1)
   
   U.S. Geological Survey

   345 Middlefield Road MS 999

   Menlo Park, CA
   

   USA

   (650) 329-5078 (voice)

   (650) 329-5190 (FAX)
2. What's the catalog number I need to order this data set? Downloadable Data
3. What legal disclaimers am I supposed to read?

   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.

4. How can I download or order the data?
   • Availability in digital form:

     Data format:	tab-delimited ASCII text files. in format MGD77t (version 10) MGD77 Size: 3.7
     Network links:	http://www.ngdc.noaa.gov/mgg/trk/trackline/samuel_p._lee/l284an/mgd77/

   • Cost to order the data: None

Who wrote the metadata?

Dates:

Last modified: 19-Oct-2020

Metadata author:

Gregory K. Miller

U.S. Geological Survey

Physical Scientist

U.S. Geological Survey, 600 Fourth Street South

St. Petersburg, FL

USA

(727) 803-8747, ext. 3020 (voice)

gmiller@usgs.gov

Metadata standard:

FGDC Content Standards for Digital Geospatial Metadata (FGDC-STD-001-1998)