Survey Identifier: TUGA01WT
Format Acronym: MGD77
Data Center File Number: 15040191
Parameters Surveyed Code: 55511
File Creation Date (yyyymmdd): 19
Source Institution: SCRIPPS INSTITUTION OF OCEANOGRAPHY
Country: USA
Platform Name: R/V T.WASHINGTON
Platform Type Code: 1
Platform Type: SHIP
Chief Scientist(s): J. ORCUTT
Project: TORTUGA LEG 1
Funding: NSF OCE87-02835
Survey Departure Date (yyyymmdd): 19871016
Port of Departure: SAN DIEGO, CALIF.
Survey Arrival Date (yyyymmdd): 19871106
Port of Arrival: PUERTO QUETZAL, GUATAMALA
Navigation Instrumentation: SATNAV/GPS,AUTO LOG GYRO+2D DOPPLER SPD
Geodetic Datum/Position: LINEAR INTERP.BETWEEN ADJACENT FIXES
Bathymetry Instrumentation: SEABEAM VERT.BEAM(2&2/3DEG)&3.5KHZ(WIDE)
Additional Forms of Bathymetric Data: ANAL.REC,35MM FILM,DIGITAL MAG. TAPE
Magnetics Instrumentation: GEOMETRICS MAGNETOMETER MOD G-801/3
Additional Forms of Magnetics Data: ANAL.REC,35MM FILM,DIGITAL MAG. TAPE
Gravity Instrumentation: BELL BGM-3 METER
Additional Forms of Gravity Data: DIGITAL MAG.TAPE
Topmost Latitude of Survey: +33
Bottommost Latitude: +01
Leftmost Longitude: -118
Rightmost Longitude: -090
General Digitizing Rate of Bathymetry: 010
General Sampling Rate of Bathymetry: 1PING IN H20
Assumed Sound Velocity: 15000
Bathymetric Datum Code: 00
Interpolation Scheme: 1 MINUTE AVERAGES EXTRACTED FROM SEABEAM VERTICAL BEAMS
General Digitizing Rate of Magnetics: 010
General Sampling Rate of Magnetics: 06
Reference Field Code: 03
Reference Field: IGRF-1985
Method of Applying Residual Field: LIN.INTERP.POINTS WITHIN ONE DEGREE SQUARE
General Digitizing Rate of Gravity: 010
General Sampling Rate of Gravity: 10
Theoretical Gravity Formula Code: 3
Theoretical Gravity Formula: IAG SYSTEM 1967
Reference System Code: 3
Reference System: IGSN-71
Departure Base Station Gravity: 9795353
Departure Base Station Description: SIO MAR FAC PIER, SAN DIEGO
Arrival Base Station Gravity: 9782889
Arrival Base Station Description: DOD0172-1,SAN JOSE,GUAT.
Additional Documentation: PROCESSED BY GEOLOGICAL DATA CENTER, SCRIPPS INSTITUTION OF OCEANOGRAPHY, DEPTHS CORRECTED FOR 5 METER SHIP DRAFT. GRAVITY HAS SPIKES AND STEPS FROM RESIDUAL NAVIGATION ERRORS. GRAVITY REPROCESSED NOV. 1988, NGDC has multibeam bathymetric data for this cruise, however the tracklines, found here in GEODAS may not exactly correspond to the multibm data available.
Number of Data Records: 29865
Min/Max Data Record:
Date: 1987 10 16
Latitude: +1.66683
Longitude: -117.22417
Bathymetry, 2- Way Traveltime: 006080
Bathymetry, Corrected Depth: 452.0
Magnetics Total Field, 1st Sensor: 323010
Magnetics Residual Field: -04600
Observed Gravity: 9775709
Free-Air Anomaly: -4590
Min/Max Data Record:
Date: 1987 11 06
Latitude: +32.65217
Longitude: -90.77752
Bathymetry, 2- Way Traveltime: 080573
Bathymetry, Corrected Depth: 6098.0
Magnetics Total Field, 1st Sensor: 479890
Magnetics Residual Field: +05961
Observed Gravity: 9795184
Free-Air Anomaly: +1333