Survey Identifier: L481NC


Format Acronym: MGD77
Data Center File Number: 06050053
Parameters Surveyed Code: 05500
File Creation Date (yyyymmdd): 19870617
Source Institution: USGS Branch of Pacific Marine Geology
Country: United States
Platform Name: Lee
Platform Type Code: 1
Platform Type: SHIP
Chief Scientist(s): Dave McCulloch
Survey Departure Date (yyyymmdd): 19810512
Port of Departure: LV REDWOOD CITY CA
Survey Arrival Date (yyyymmdd): 19810518
Port of Arrival: AR EUREKA CA
Navigation Instrumentation: SATNAV, MINIRANGER
Geodetic Datum/Position: PRIM-INTEGRATED NAV, SEC-MINIRANGER
Bathymetry Instrumentation: 12KHZ NARROW 1 SEC, 3.5 KHZ WIDE 1 SEC
Additional Forms of Bathymetric Data: RECORDER ROLLS
Magnetics Instrumentation: PROTON PRECESSION MAG-GEOMETRICS G-801
Additional Forms of Magnetics Data: ANALOG RECORDS
Gravity Instrumentation: L&R S-53
Additional Forms of Gravity Data: ANALOG RECORDS
Seismic Instrumentation: UNIBOOM, SINGLE CHANNEL
Topmost Latitude of Survey: +40
Bottommost Latitude: +37
Leftmost Longitude: -125
Rightmost Longitude: -122
General Sampling Rate of Bathymetry: 20/SECONDS
Assumed Sound Velocity: 14630
General Digitizing Rate of Magnetics: 10
General Sampling Rate of Magnetics: 04
Magnetic Sensor Tow Distance: 213
Reference Field Code: 04
Reference Field: IGRF-75
Method of Applying Residual Field: LINEAR INTERP. BETWEEN NAV POINTS
General Digitizing Rate of Gravity: 10
General Sampling Rate of Gravity: 15
Theoretical Gravity Formula Code: 2
Theoretical Gravity Formula: INTERNAT, IAG1967
Reference System Code: 3
Reference System: SYSTEM IGSN-71
Corrections Applied: DRIFT CORRECTIONS
Departure Base Station Gravity: 9688450
Departure Base Station Description: REDWOOD CITY, CA.
Arrival Base Station Gravity: 9688451
Arrival Base Station Description: EUREKA, CA.
Number of Data Records: 8015

Min/Max Data Record:
Date: 1981 05 12
Latitude: +37.10287
Longitude: -124.23451
Magnetics Total Field, 1st Sensor: 442300
Magnetics Residual Field: -69760
Observed Gravity: 9798801
Free-Air Anomaly: -0831

Min/Max Data Record:
Date: 1981 05 18
Latitude: +39.99066
Longitude: -122.18615
Magnetics Total Field, 1st Sensor: 604560
Magnetics Residual Field: +92109
Observed Gravity: 9802370
Free-Air Anomaly: +9689