Survey Identifier: HM7503


Format Acronym: MGD77
Data Center File Number: J1030010
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): MISAO SAKURAI
Project: THE BASIC MAP OF SEA OF CONTINENTAL SHELVES
Survey Departure Date (yyyymmdd): 19750519
Port of Departure: TOKYO
Survey Arrival Date (yyyymmdd): 19750623
Port of Arrival: TOKYO
Navigation Instrumentation: DECCA 7C/MP
Geodetic Datum/Position: DECCA 7C/MP
Bathymetry Instrumentation: 50KHZ,BEAM-WIDTH 15-DEGREE*2
Additional Forms of Bathymetric Data: ANAROG RECORD
Magnetics Instrumentation: PROTON MAG
Additional Forms of Magnetics Data: TOTAL INTENSITY CHART 6343M,6344M
Gravity Instrumentation: TSSG-H3 SENSOR:P4
Additional Forms of Gravity Data: FREE AIR ANOMALY CHART 6333G,6334G
Seismic Instrumentation: AIR GUN
Formats of Seismic Data: ANALOG RECORD
Topmost Latitude of Survey: +36
Bottommost Latitude: +33
Leftmost Longitude: +130
Rightmost Longitude: +132
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: DGRF
Method of Applying Residual Field: DIURNAL CORRECTION 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: 9797700
Departure Base Station Description: TOKYO 35-28.2N,139-46.5E JGSN75
Arrival Base Station Gravity: 9796770
Arrival Base Station Description: MOZI 33-56.5N,130-57.4E
Additional Documentation: CRUISE NAME:YAMAGUCHI OKI, OBSERVERS:T.YANAGI AND T.KANAZAWA, HAKATA 33-36.4N,130-24.0 979635 MGAL JGSN 75, REDUCTION AND COMPILATION OF GRAVITY DATA HAVE BEEN MADA BY T.YANAGI, AND A.NISISITA OF THE ASTRONOMICAL DIV,JHD. magnetics records follow bathy,grav. no times for mag OLD NGDC:56070010
Number of Data Records: 5709

Min/Max Data Record:
Date: 1975 05 31
Latitude: +33.67139
Longitude: +130.06416
Bathymetry, Corrected Depth: 32.0
Magnetics Total Field, 1st Sensor: 470700
Magnetics Residual Field: -05870
Observed Gravity: 9796576
Free-Air Anomaly: -0510

Min/Max Data Record:
Date: 1975 06 21
Latitude: +35.95632
Longitude: +131.89230
Bathymetry, Corrected Depth: 1460.0
Magnetics Total Field, 1st Sensor: 486300
Magnetics Residual Field: +09774
Observed Gravity: 9798348
Free-Air Anomaly: +0858