Overview

The primary function of the Underway Geophysics lab is to acquire navigation and bathymetric (3.5 and 12 kHz) data, and provide and maintain the sound sources used for check shots and vertical seismic profile experiments. In addition to their scientific uses, geophysical data are used to ensure the drilling safety of the ship by confirming site positions and identifying potentially dangerous seafloor and subseafloor characteristics. The lab also supports downhole vertical seismic profiling and can collect magnetic data while underway.

Instruments

Seismic Sound Sources

• Sercel 210 in³ GI Gun pneumatic sound source: configurable to "True GI Mode" and up to 255 total in³; used as a sound source for downhole logging operations and towed seismic surveys
• Sercel G. Gun Parallel Cluster pneumatic sound source: the cluster is composed of two 250 in³ G. Guns separated by 1 meter; used as a sound source for downhole logging operations

Bathymetry

• SyQwest Bathy 2010 CHIRP Sub-bottom Profiler and Bathymetric Echo Sounder: 3.5 kHz frequency obtained with a 12 x TR-109 transducer array driven by a 10 kW power amplifier; 12 kHz frequency obtained with an EDO-323C transducer
• Transducers are housed in the forward sonar dome
• Two EPC Model 9802 Thermal Graphic Recorders

Navigation

• Integrated navigation software
• Two Trimble SPS351 GPS units antennas

Magnetics

• Marine Magnetics SeaSpy M-SS1001 Towed Magnetometer

Bathymetry

• Bathy2010 Quick Start Guide
• Bathy2010 User Guide
• Depth Correction
• Converting SyQwest Bathy-2010 ODC files to SEGY files

Magnetometer (Maggie)

• Maggie Quick User Guide_378P
• Maggie Cheat Sheet_378P

Navigation

• Winfrog CookbookUser Guide_378P
• JRNav Google Earth_378P
• JRData Server_378P
• Site Fix