Survey Identifier: HM7103
Format Acronym: MGD77
Data Center File Number: J1030005
Parameters Surveyed Code: 55513
File Creation Date (yyyymmdd): 19801222
Source Institution: HYDROGRAPHIC DEPT.
Country: JAPAN
Platform Name: MEIYO
Platform Type Code: 1
Platform Type: SHIP
Chief Scientist(s): MANABU ONO
Project: THE BASIC MAP OF SEA OF CONTINENTAL SHELVES
Survey Departure Date (yyyymmdd): 19710701
Port of Departure: WAKKANAI
Survey Arrival Date (yyyymmdd): 19710804
Port of Arrival: ABASHIRI
Navigation Instrumentation: HOKKAIDO DECCA CHAIN (9CM/MP)
Geodetic Datum/Position: HOKKAIDO DECCA CHAIN (9CM/MP)
Bathymetry Instrumentation: 50KHZ,BEAM-WIDTH 15-DEGREE*2
Additional Forms of Bathymetric Data: ANALOG RECORD
Magnetics Instrumentation: PROTON MAG
Additional Forms of Magnetics Data: TOTAL INTENSITY CHART 6382M,6381M
Gravity Instrumentation: TSSG-H1,SENSOR:P1
Additional Forms of Gravity Data: FREE AIR ANOMALY CHART 6381G,6382G
Seismic Instrumentation: AIR GUN
Formats of Seismic Data: ANALOG RECORD
Topmost Latitude of Survey: +46
Bottommost Latitude: +43
Leftmost Longitude: +139
Rightmost Longitude: +146
General Digitizing Rate of Bathymetry: 100
General Sampling Rate of Bathymetry: 1/SECOND
Assumed Sound Velocity: 15000
Bathymetric Datum Code: 07
General Digitizing Rate of Magnetics: 050
General Sampling Rate of Magnetics: 06
Magnetic Sensor Tow Distance: 250
Reference Field Code: 03
Reference Field: IGRF-65
Method of Applying Residual Field: DIRUNAL CORRECTIONS USING OBSERVATORY DATA
General Digitizing Rate of Gravity: 100
General Sampling Rate of Gravity: 00
Theoretical Gravity Formula Code: 3
Theoretical Gravity Formula: IAG SYSTEM(1967)
Reference System: SYSTEM JGSN75
Corrections Applied: DRIFT,ETOVOS
Departure Base Station Gravity: 9806180
Departure Base Station Description: ABASHIRI 44-01.1N,14417.3E
Arrival Base Station Gravity: 9806550
Arrival Base Station Description: WAKKANAI 45-24.3,141-41.2E
Additional Documentation: CRUISE NAME:SOYA ABASHIRI OKI, OBSERVERS:H.NISHISHITA AND Y.TOMIOKA, MONBETSU 44-21.1,143-21.9E 980620 MGAL, REDUCTION AND COMPILATION OF GRAVITY DATA HAVE BEEN MADE BY T.TAKEMURA, T.YANAGI AND Y.TOMIOKA OF THE ASTRONOMICAL DIV. CONVERSION POPOTSDAM INTO, IGSN 71 HAS CARRIED OUT BY Y.GANEKO. magnetics records follow bathy and grav. no times for mag OLD NGDC:56070005
Number of Data Records: 6720
Min/Max Data Record:
Date: 1971 07 11
Latitude: +43.95545
Longitude: +139.58845
Bathymetry, Corrected Depth: 14.0
Magnetics Total Field, 1st Sensor: 490200
Magnetics Residual Field: -07875
Observed Gravity: 9805332
Free-Air Anomaly: -0505
Min/Max Data Record:
Date: 1971 09 30
Latitude: +45.60566
Longitude: +145.10386
Bathymetry, Corrected Depth: 1460.0
Magnetics Total Field, 1st Sensor: 519300
Magnetics Residual Field: +09607
Observed Gravity: 9807462
Free-Air Anomaly: +0782