UNDERWAY GEOPHYSICS LAB

Roy Davis/Ty Cobb

Summary

The magnetometer was deployed on the transit from Balboa, Panama to the first site of Expedition 344 (U1381). Bathymetric data was collected on all transits, including return visit to site U1412.

Data Summary

Transits:St. Johns to Balboa (L1T ≈ 2,801 nm)
Balboa to U1381 (L2T ≈ 416 nm)
U1381 to U1380 (L3T ≈ 11 nm)
U1380 to U1412 (L4T ≈ 7.0 nm)
U1412 to U1413 (L5T ≈ 15 nm)
U1413 to U1412 (L6T ≈ 15 nm)
U1412 to U1414 (L7T ≈ 6.0 nm)
U1414 to Puntarenas (L8T ≈ 95 nm)
Sites: U1381 C
U1380 B/C
U1412 A/B/C/D
U1413 A
U1414 A

Site fixes were performed at each site/hole.
Event data points were gathered every sixty seconds when underway and every thirty seconds when on-site.

Equipment Performance Summary:

WinFrog

WinFrog1 was used entirely for primary navigation acquisition. There were no problems encountered. WinFrog2 was available as backup host.

Trimble GPS

The aft/forward Triple GPSs were the primary GPSs used for the duration of Expedition 344T/344. No problems were encountered. A Triple GPS unit was available as backup.
.

Bathy 2010

No problems were encountered during the Expedition. WinFrog2 was used as primary host during Expedition.

Data Backups

data files for the Expedition were copied to:
\\JR1\Vol1\data1\1.5 Ops Navigation
\\JR1\Vol1\data1\1.6 Ops Bathymetry - PDR pulse depth recorder

FANTAIL

Gus

Summary

Bathymetric and navigational data was collected throughout the expedition. The towed magnetometer was only used on the transit from Panama to the first site location.
The seismic gun array was prepared for possible V.S.I. use. The array was not used due to poor drill hole conditions which hampered logging operations.

Special projects

Seismic guns have been rigged down, disassembled, cleaned and reassembled for long term storage without seals and o-rings

Problems encountered

Level wind on port winch
Excessive lateral endplay with the leveler drive screw was corrected with the installation of a capture plate on the outboard side of the inboard frame.
The leveler fleet angle sensor was found to be faulty and removed. A new one was ordered. Another erratic problem while manually controlling the leveler was noted. The drive screw would stop and abruptly jog several inches to port for no apparent reason. The motherboard was removed and numerous switch components and op amps replaced. A bias adjustment pot was installed which causes the board to think there is a fleet angle sensor signal. The leveler is operational in manual mode.

Miscellaneous

Routine maintenance performed as necessary.