Survey Identifier: HT93T331
Format Acronym: MGD77
Data Center File Number: J1010074
Parameters Surveyed Code: 55500
File Creation Date (yyyymmdd): 19980123
Source Institution: HYDROGRAPHIC DEPARTMENT
Country: JAPAN
Platform Name: TAKUYO
Platform Type Code: 1
Platform Type: SHIP
Chief Scientist(s): FUMIO KUMASAKA
Project: 33TH AREA CONTINENTAL SHELF SURVEY (HEISEI5-FOURTH)
Funding: HYDROGRAPHIC DEP
Survey Departure Date (yyyymmdd): 19931102
Port of Departure: TOKYO,JAPAN
Survey Arrival Date (yyyymmdd): 19931119
Port of Arrival: TOKYO,JAPAN
Navigation Instrumentation: GPS/LORAN-C
Geodetic Datum/Position: INTEGRATED NAVIGATION SYSTEM
Bathymetry Instrumentation: SEA-BEAM BATHYMETRIC SYSTEM 12KHZ
Magnetics Instrumentation: PROTON MAGUNETMETER (PMM-100)
Gravity Instrumentation: ONBOARD GRAVIMETER SYSTEM (GMBH KSS-30)
Topmost Latitude of Survey: +19
Bottommost Latitude: +17
Leftmost Longitude: +137
Rightmost Longitude: +141
General Digitizing Rate of Bathymetry: 10
Assumed Sound Velocity: 1500
Bathymetric Datum Code: 05
General Digitizing Rate of Magnetics: 10
General Sampling Rate of Magnetics: 60
Magnetic Sensor Tow Distance: 252
Reference Field Code: 88
Reference Field: IGRF1990
General Digitizing Rate of Gravity: 10
General Sampling Rate of Gravity: 5
Theoretical Gravity Formula Code: 3
Theoretical Gravity Formula: r1967
Reference System: JGSN75
Corrections Applied: DRIFT & EOTVOS CORRECTION
Departure Base Station Gravity: -8702
Departure Base Station Description: JHDGO(TOKYO PORT)
Arrival Base Station Gravity: -8700
Arrival Base Station Description: JHDGO(TOKYO PORT)
Additional Documentation: Corection for sound velocity was applied to the seabeam data using tables for, the area No.53 in Echo-sounding Correction Tables NP 139 (Hydrographic Dept. UK,1980). The correction for time variations were carried out with the geomagnetic, variations at the Titisima & the Hatijo data of Magnetic Observatory,JMA.
Number of Data Records: 87
Min/Max Data Record:
Date: 1993 11 11
Latitude: +17.89933
Longitude: +137.50434
Bathymetry, Corrected Depth: 3980.0
Magnetics Residual Field: -01160
Free-Air Anomaly: -0850
Min/Max Data Record:
Date: 1993 11 11
Latitude: +18.01300
Longitude: +140.01068
Bathymetry, Corrected Depth: 6850.0
Magnetics Residual Field: +00040
Free-Air Anomaly: +0330