U.S. Geological Survey
Coastal and Marine Geology Program
2013
l780bs.m77t - MGD77 data file for Geophysical data from field activity L-7-80-BS in Bering Sea, Alaska from 08/01/1980 to 08/26/1980
tab-delimited ASCII text files
Menlo Park, CA
U.S. Geological Survey
http://www.ngdc.noaa.gov/mgg/trk/trackline/samuel_p._lee/l780bs/mgd77/
Wm. Clinton Steele
Carolyn H. Degnan
Gary B. Deeter
Jean A. Riordan
1980
DESCRIPTION OF MARINE GEOPHYSICAL DATA COLLECTED BY THE U.S. GEOLOGICAL SURVEY AND HOW TO OBTAIN IT
1.0
Digital Document
U.S. Geological Survey Open File Report
167
Menlo Park, CA
U.S. Geological Survey
http://pubs.usgs.gov/of/1989/0167/report.pdf
Single-beam bathymetry and gravity data along with DGPS navigation data was collected as part of field activity L-7-80-BS in Bering Sea, Alaska from 08/01/1980 to 08/26/1980, http://walrus.wr.usgs.gov/infobank/l/l780bs/html/l-7-80-bs.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/l780bs/html/l-7-80-bs.bath.html and http://walrus.wr.usgs.gov/infobank/l/l780bs/html/l-7-80-bs.grav.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.
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/ ).
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.
19800801
19800826
ground condition
None planned
-172.71823
-163.16579
66.03701
62.68804
USGS Metadata Identifier
USGS:431deaf5-8793-467f-8a82-c4b675ea6bc2
ISO 19115 Topic Category
geoscientificinformation
oceans
None
Marine Geology
Marine Geophysics
Marine Gravity Field
Bathymetry
Water Depth
Seafloor Topography
Data Categories for Marine Planning
distributions
bathymetry and elevation
Marine Realms Information Bank (MRIB) keywords
single-beam echo sounder
gravimetry
marine geophysics
USGS Thesaurus
single-beam echo sounder
bathymetry measurement
bathymetry
gravimeter measurement
marine geophysics
Geographic Names Information System (GNIS)
AK
Alaska
Bering Sea
Bering Sea, Alaska
USA
None. These data are held in the public domain.
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.
Gregory K. Miller
U.S. Geological Survey
Physical Scientist
mailing and physical
600 4th Street South
St. Petersburg
FL
33701
USA
(727) 803-8747, ext. 3020
gmiller@usgs.gov
Hans Nelson (Chief Scientist)
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
Boulder, CO
National Geophysical Data Center, National Oceanic and Atmospheric Administration
25 p.
http://www.ngdc.noaa.gov/mgg/dat/geodas/docs/mgd77.pdf
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.
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.
Start and end date/times of data >Navigation Data (l-7-80-bs.052 [SINS]) >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >198008012052000 198008192358000 >198008200104000 198008200402000 >198008200516000 198008200542000 >198008200650000 198008200650000 >198008200826000 198008200916000 >198008201046000 198008201108000 >198008201156000 198008201234000 >198008201342000 198008201342000 >198008201534000 198008201600000 >198008201826000 198008201826000 >198008201934000 198008202048000 >198008202200000 198008202228000 >198008210000000 198008210000000 >198008210048000 198008210048000 >198008210148000 198008210204000 >198008210356000 198008210454000 >198008210600000 198008210750000 >198008210832000 198008220038000 >198008220137000 198008251034000 >198008251152000 198008251152000 >198008251336000 198008251336000 >198008251522000 198008251522000 >198008251606000 198008251606000 >198008251708000 198008251708000 >198008251754000 198008251754000 >198008251902000 198008252152000 >198008252338000 198008252338000 >198008260132000 198008260132000 >198008260334000 198008260334000 >198008260422000 198008260422000 >198008260524000 198008260524000 >198008260606000 198008260606000 >198008260654000 198008260654000 >198008260846000 198008260858000 >198008260942000 198008260942000 >198008261042000 198008261248000 >198008261414000 198008261432000 >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >Gravity Data (l-7-80-bs.111_052) >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >198008012126200 198008022015400 >198008022021210 198008041136200 >198008041153120 198008041344200 >198008041401330 198008041404200 >198008041411500 198008041906200 >198008041919300 198008042058200 >198008042107030 198008051608100 >198008081310500 198008091115400 >198008091133090 198008100032300 >198008100038190 198008111237100 >198008111242310 198008112222000 >198008112228490 198008120819000 >198008120827370 198008130040000 >198008140200170 198008140942200 >198008141005300 198008141123200 >198008141135530 198008141300200 >198008141326030 198008141640200 >198008141648470 198008141928200 >198008141935040 198008171911400 >198008171919240 198008181323200 >198008210900020 198008221051200 >198008221109480 198008221532000 >198008221538520 198008230945400 >198008230955210 198008241931100 >198008241953420 198008250644300 >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >Bathymetry Data (l-7-80-bs.335_052) >YYYYMMDDHHMMSST YYYYMMDDHHMMSST >198008012115000 198008012128000 >198008012135000 198008012209000 >198008012229000 198008012229000 >198008012245000 198008020326000 >198008020332000 198008020620000 >198008020636000 198008020706000 >198008020736000 198008020934000 >198008020945000 198008021202000 >198008021208000 198008022103000 >198008030009000 198008030034000 >198008030040000 198008030144000 >198008030445000 198008030839000 >198008030845000 198008030914000 >198008031320000 198008031404000 >198008031410000 198008031439000 >198008040120000 198008040309000 >198008040315000 198008040405000 >198008040445000 198008040514000 >198008041536000 198008041624000 >198008041630000 198008041734000 >198008041747000 198008041814000 >198008041820000 198008041859000 >198008041905000 198008050019000 >198008050025000 198008050355000 >198008050405000 198008050414000 >198008050420000 198008050440000 >198008052150000 198008052300000 >198008052306000 198008060138000 >198008060144000 198008060149000 >198008060155000 198008060200000 >198008060206000 198008060219000 >198008060225000 198008060239000 >198008060245000 198008060654000 >198008060700000 198008061023000 >198008061030000 198008061653000 >198008061717000 198008061849000 >198008061855000 198008061955000 >198008062020000 198008062319000 >198008062325000 198008062329000 >198008062335000 198008070210000 >198008070937000 198008071510000 >198008080222000 198008080411000 >198008080427000 198008080459000 >198008080505000 198008080519000 >198008080525000 198008080539000 >198008080545000 198008080924000 >198008080930000 198008081039000 >198008081045000 198008081434000 >198008081440000 198008081938000 >198008081950000 198008082019000 >198008082025000 198008082039000 >198008082045000 198008082137000 >198008082205000 198008082358000 >198008090007000 198008090424000 >198008090430000 198008090828000 >198008090840000 198008090945000 >198008090955000 198008091454000 >198008091500000 198008091519000 >198008091525000 198008091659000 >198008091705000 198008091749000 >198008091755000 198008092154000 >198008092235000 198008100304000 >198008100310000 198008100909000 >198008100915000 198008101424000 >198008101430000 198008101614000 >198008101620000 198008101724000 >198008101730000 198008101750000 >198008101840000 198008102344000 >198008102350000 198008110930000 >198008110945000 198008111415000 >198008111425000 198008111615000 >198008112105000 198008112154000 >198008112200000 198008112209000 >198008112215000 198008112229000 >198008112235000 198008120104000 >198008120110000 198008120309000 >198008120315000 198008120545000 >198008120651000 198008120738000 >198008120750000 198008120839000 >198008120845000 198008121524000 >198008121530000 198008121539000 >198008121545000 198008122130000 >198008140450000 198008140915000 >198008141030000 198008141350000 >198008141405000 198008141510000 >198008141516000 198008141544000 >198008141550000 198008141749000 >198008141755000 198008141759000 >198008141805000 198008142043000 >198008142054000 198008142207000 >198008142356000 198008142356000 >198008150020000 198008150049000 >198008150215000 198008150254000 >198008150500000 198008150553000 >198008150640000 198008150700000 >198008150845000 198008151147000 >198008151436000 198008151514000 >198008151520000 198008151945000 >198008151951000 198008152014000 >198008152030000 198008152205000 >198008152248000 198008160249000 >198008160255000 198008160709000 >198008160715000 198008160809000 >198008160815000 198008161310000 >198008161321000 198008162114000 >198008162120000 198008170050000 >198008170110000 198008170430000 >198008170452000 198008170845000 >198008170855000 198008171254000 >198008171300000 198008171329000 >198008171335000 198008171354000 >198008171400000 198008171544000 >198008171550000 198008171950000 >198008172000000 198008180330000 >198008180340000 198008180704000 >198008180710000 198008180849000 >198008180855000 198008180939000 >198008180945000 198008181115000 >198008181126000 198008181450000 >198008181530000 198008182334000 >198008182340000 198008190214000 >198008190226000 198008190348000 >198008191930000 198008200008000 >198008200646000 198008200654000 >198008200700000 198008200804000 >198008200810000 198008200914000 >198008200920000 198008201009000 >198008201015000 198008201030000 >198008201040000 198008201219000 >198008201225000 198008201254000 >198008201300000 198008201323000 >198008201720000 198008201934000 >198008202001000 198008202205000 >198008202215000 198008202250000 >198008202301000 198008202319000 >198008210230000 198008210329000 >198008210335000 198008210815000 >198008210822000 198008210847000 >198008211107000 198008211358000 >198008211608000 198008211825000 >198008211905000 198008220049000 >198008220055000 198008220809000 >198008220815000 198008220955000 >198008221005000 198008221145000 >198008221315000 198008221410000 >198008221700000 198008221930000 >198008222145000 198008222350000 >198008230120000 198008230300000 >198008230835000 198008230935000 >198008230945000 198008231125000 >198008231236000 198008231450000 >198008231625000 198008231655000 >198008231710000 198008231815000 >198008232210000 198008232254000 >198008232300000 198008232345000 >198008240235000 198008240419000 >198008240425000 198008240540000 >198008240810000 198008240919000 >198008241115000 198008241154000 >198008241200000 198008241235000 >198008241445000 198008241619000 >198008241625000 198008241819000 >198008241825000 198008241954000 >198008242000000 198008242105000 >198008242116000 198008242139000 >198008242145000 198008242324000 >198008242330000 198008250220000 >198008250226000 198008250248000 >198008250300000 198008250358000 >198008250650000 198008251124000 >198008251130000 198008251354000 >198008251400000 198008251404000 >198008251410000 198008251522000 >198008251531000 198008251559000 >198008251605000 198008251704000 >198008251710000 198008251749000 >198008251755000 198008251959000 >198008252005000 198008260024000 >198008260030000 198008260633000 >198008260645000 198008260749000 >198008260755000 198008260854000 >198008260900000 198008261224000 >198008261230000 198008261254000 >198008261300000 198008261419000 >198008261425000 198008261430000 >YYYYMMDDHHMMSST YYYYMMDDHHMMSST
Unspecified
Unspecified
Navigation Data >Converted to time format with year at start. > >11/26/85 EDM DUA0:[DATA.DRSDATA.NAVL.L780BS]L780BS.052; >DRB0:[DRS.REFMT]REFORMAT.EXE;5 >
19960119
U.S. Geological Survey (USGS) , Coastal and Marine Geology (CMG)
Carolyn H. Degnan
Geophysicist
mailing and physical address
USGS Pacific Coastal & Marine Science Center, 400 Natural Bridges Drive
Santa Cruz
CA
95060-5792
USA
(831) 460-7452
(831) 427-4748
infobank@octopus.wr.usgs.gov
Gravity Data >10/31/1998 /tiger/l/l780bs/grav/l-7-80-bs.111_052 >/bear/programs/edit/automerge/automerge > >Input was... >Converted to time format with year at start. > >11/12/85 BARB DRS$DATA:[L780BS.G]L780BS.111; >DRB0:[DRS.REFMT]REFORMAT.EXE;4 > >Input was... >Converted to time format with year at start. > >11/26/85 EDM DUA0:[DATA.DRSDATA.NAVL.L780BS]L780BS.052; >DRB0:[DRS.REFMT]REFORMAT.EXE;5 > >time, lat, long, time(sec) to nearest nav fix, data values
19981031
U.S. Geological Survey (USGS) , Coastal and Marine Geology (CMG)
Carolyn H. Degnan
Geophysicist
mailing and physical address
USGS Pacific Coastal & Marine Science Center, 400 Natural Bridges Drive
Santa Cruz
CA
95060-5792
USA
(831) 460-7452
(831) 427-4748
infobank@octopus.wr.usgs.gov
Bathymetry Data >10/31/1998 /tiger/l/l780bs/bath/l-7-80-bs.335_052 >/bear/programs/edit/automerge/automerge > >Input was... >Converted to time format with year at start. > >09/06/85 BECKIE DUA0:[DATA.L780BS.B]L780BS.335; >DRB0:[DRS.BAT]BATRED.EXE;1 >This file was hand-digetized in 2-way traveltime(secs). > >09/06/85 BECKIE DUA0:[DATA.L780BS.B]L780BS.310; >DRB0:[DRS.NGDC]UNREFNGDC.EXE; > >Input was... >Converted to time format with year at start. > >11/26/85 EDM DUA0:[DATA.DRSDATA.NAVL.L780BS]L780BS.052; >DRB0:[DRS.REFMT]REFORMAT.EXE;5 > >time, lat, long, time(sec) to nearest nav fix, data values
19981031
U.S. Geological Survey (USGS) , Coastal and Marine Geology (CMG)
Carolyn H. Degnan
Geophysicist
mailing and physical address
USGS Pacific Coastal & Marine Science Center, 400 Natural Bridges Drive
Santa Cruz
CA
95060-5792
USA
(831) 460-7452
(831) 427-4748
infobank@octopus.wr.usgs.gov
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.
20120620
U.S. Geological Survey (USGS), Coastal and Marine Geology (CMG)
Carolyn H. Degnan
Geophysicist
mailing and physical address
USGS Pacific Coastal & Marine Science Center, 400 Natural Bridges Drive
Santa Cruz
CA
95060-5792
USA
(831) 460-7452
(831) 427-4748
infobank@octopus.wr.usgs.gov
Keywords section of metadata optimized for discovery in USGS Coastal and Marine Geology Data Catalog.
20170201
U.S. Geological Survey
Alan O. Allwardt
Contractor -- Information Specialist
mailing and physical address
2885 Mission Street
Santa Cruz
CA
95060
831-460-7551
831-427-4748
aallwardt@usgs.gov
Edited metadata to add keywords section with USGS persistent identifier as theme keyword. No data were changed.
20201019
U.S. Geological Survey
VeeAnn A. Cross
Marine Geologist
Mailing and Physical
384 Woods Hole Road
Woods Hole
MA
02543-1598
508-548-8700 x2251
508-457-2310
vatnipp@usgs.gov
Bering Sea, Alaska
Point
Point
0.000001
0.000001
Decimal degrees
D_WGS_1984
WGS_1984
6378137.000000
298.25722210100002
l780bs.m77t
MGD77T single-beam bathymetry and gravity data file for L780BS
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
NGDC
This identifier varies in format and is supplied by the contributing organization
TIMEZONE
Time-zone correction
NGDC
In our datasets, no correction was applied. All values equal 0.
DATE
YYYYMMDD
NGDC
19800801
19800826
Year, month, day
TIME
Time
NGDC
0
2359
hours and decimal minutes
LAT
Latitude
World Geodetic System 1984 Geographic Coordinate System
62.68804
66.03701
decimal degrees
LON
Longitude
World Geodetic System 1984 Geographic Coordinate System
-172.71805
-163.16592
decimal degrees
POS_TYPE
Indicates how lat/lon was obtained
NGDC
1
3
1 = observed fix, 3 = interpolated fix, nil = unspecified
BAT_TTIME
Bathymetry, 2-way travel time
U.S. Geological Survey
0.007
0.076
seconds
CORR_DEPTH
Bathymetry, corrected depth
U.S. Geological Survey
5.3
57
decimal meters
BAT_CPCO
Bathymetric Correction code - details the procedure used for determining the sound velocity correction to depth
NGDC
63
63
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
NGDC
1
3
1 - Observed, 3 - Interpolated (Header Seq. 12), 9 - Unspecified
Bathymetry, gravity, and navigation data for U.S. Geological Survey bathymetry survey L780BS in MGD77T format.
Attributes are obtained from MGD77T data files created from the navigation, gravity, 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.
U.S. Geological Survey
mailing and physical address
345 Middlefield Road MS 999
Menlo Park
CA
94025
USA
(650) 329-5078
(650) 329-5190
Downloadable Data
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.
MGD77t
10
MGD77
tab-delimited ASCII text files.
1.3
http://www.ngdc.noaa.gov/mgg/trk/trackline/samuel_p._lee/l780bs/mgd77/
Data are available for download on the World Wide Web (WWW).
None
20201019
Gregory K. Miller
U.S. Geological Survey
Physical Scientist
mailing and physical address
U.S. Geological Survey, 600 Fourth Street South
St. Petersburg
FL
33701
USA
(727) 803-8747, ext. 3020
gmiller@usgs.gov
FGDC Content Standards for Digital Geospatial Metadata
FGDC-STD-001-1998