2019 Geophysical surveys and instrumented tripod deployment in and around Astoria Canyon

Science Center Objects

Objectives: Examine the processes associated with sediment storage and remobilization in and around Astoria Canyon to understand the processes that lead to turbidity flows.

These surveys are part of the USGS project, “Cascadia Subduction Zone Marine Geohazards.”

Illustration of the seafloor off the coast with areas highlighted to show detail.

2019 USGS geophysical surveys and instrumented tripod deployment in and around Astoria Canyon

Participants

USGS Scientists: Jenna Hill (Principal Investigator), Maureen Walton, Alicia Balster-Gee, and Gerry Hatcher; UW Scientist: Andrea Ogston (Principal Investigator); UW Students: Evan Lahr and Anna Boyar (Photo 3)

Partners

University of Washington

Platform Used

University of Washington’s R/V Rachel Carson (Photo 4)

Data collected

Sparker multi-channel seismic (MCS), Chirp sub-bottom profiler (Photo 1)

Instruments deployed

Upward and downward looking acoustic dopper current profilers (ADCPs), acoustic doppler velocimeter (ADV), acoustic suspended sediment profiler, turbidity sensors, transmissometers, conductivity-temperature-depth (CTD), photologger (Photos 2 and 5)

Highlights

  • Detailed imaging of the upper Astoria canyon system and numerous slope failures
  • Captured time series of oceanographic conditions at the head of Astoria Canyon

 

Three people kneel around a large hose and they are wrapping electrical tape around it.

Photo 1: USGS members of the science party on board R/V Rachel Carson prepare the hydrophone streamer for deployment. Credit: Jenna Hill, USGS

A group of people, wearing life jackets and hard hats, stand on the deck of a ship work to secure apiece of equipment.

Photo 2: Members of the science party and the crew of R/V Rachel Carson work to recover an instrumented tripod. Credit: Jenna Hill, USGS

Seven people stand together on the deck of a research vesselwearing life jackets and hard hats and everyone is smiling.

Photo 3: Science party from left to right: Gerry Hatcher (USGS), Maureen Walton (USGS), Jenna Hill (USGS), Andrea Ogston (UW), Anna Boyar (UW), Alicia Balster-Gee (USGS), Evan Lahr (UW). Credit: Jenna Hill, USGS

A research vessel floating on the water.

Photo 4: University of Washington’s R/V Rachel Carson. Credit – UW School of Oceanography

  

A man holds a metal tripod frame with instruments and floatation devices attached to it.

Photo 5: The instrumented tripod is successfully brought onboard for data download. Credit: Jenna Hill, USGS