Survey Identifier: HT90T231
Format Acronym: MGD77
Data Center File Number: J1010045
Parameters Surveyed Code: 55533
File Creation Date (yyyymmdd): 19960307
Source Institution: HYDROGRAPHIC DEPARTMENT
Country: JAPAN
Platform Name: TAKUYO
Platform Type Code: 1
Platform Type: SHIP
Chief Scientist(s): HIRAO MASAYOSHI
Project: 23TH AREA(FIRST)CONTINENTAL SHELF SURVEY
Funding: HYDROGRAPHIC DEP
Survey Departure Date (yyyymmdd): 19901122
Survey Arrival Date (yyyymmdd): 19901211
Port of Arrival: TOKYO,JAPAN
Navigation Instrumentation: GPS/NNSS/LORAN-C
Geodetic Datum/Position: INTEGRATED NAVIGATION SYSTEM
Bathymetry Instrumentation: SEA-BEAM BATHYMETRIC SYSTEM 12KHZ
Magnetics Instrumentation: PROTON MAGUNETMETER (GM-123,PMM-100)
Gravity Instrumentation: ONBOARD GRAVIMETER SYSTEM (GMBH KSS/30)
Topmost Latitude of Survey: +25
Bottommost Latitude: +20
Leftmost Longitude: +137
Rightmost Longitude: +141
General Digitizing Rate of Bathymetry: 10
General Digitizing Rate of Magnetics: 10
Magnetic Sensor Tow Distance: 314
Reference Field Code: 12
General Digitizing Rate of Gravity: 10
Theoretical Gravity Formula Code: 3
Reference System: JGSN 75
Departure Base Station Gravity: 9797783
Departure Base Station Description: JHDGO(TOKYO PORT)
Arrival Base Station Gravity: 9797783
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 data of Magnetic Observatory,JMA.
Number of Data Records: 2032
Min/Max Data Record:
Date: 1990 11 24
Latitude: +20.98750
Longitude: +137.48800
Bathymetry, Corrected Depth: 3220.0
Magnetics Residual Field: -02130
Free-Air Anomaly: -0110
Min/Max Data Record:
Date: 1990 12 09
Latitude: +24.01400
Longitude: +140.01150
Bathymetry, Corrected Depth: 5730.0
Magnetics Residual Field: +00490
Free-Air Anomaly: +0720