|Cascadia Initiative Year 3, LEG 3 (At26-02, EM122)
|Recover 30 Lamont Doherty Earth Observatory Ocean-bottom Seismometers (OBSs) of 3
different types: ?10 TRM shallow-water OBSs with Trillium compact 3-component absolute
pressure gauge installed at depths from 200-1000m (nominal). Recovered using remotely
operated vehicle Jason. ?10 Trawl-Resistant Mount (TRM) shallow-water OBS with Trillium
compact 3-component seismometer, absolute pressure gauge (APG), acoustic release/pop-up
buoy with Jason backup. ?10 LDEO deep water OBSs with APG. Recover by sending an acoustic
release command to drop the anchor. OBS then floats to the surface a nominal rate
of 50m/min. Referred to as LDEO-DW below. ?Iftime allows, discover and recover 2 Woods
Hole Oceanographic Institution deep water OBSs. Additional Activities: Acquire swath
bathymetry, including water column data, in transit between all stations and port.
Acquire other underway data (e.g. meterology, acoustic doppler current profiler).