Seafloor Geodesy in Alaska

My grad student, Nathalie Chavarría, and I are on-board the RV Sikuliaq at the moment deploying a bunch of transponders and a couple of autonomous surface vehicles to observe offshore fault behavior and improve on our methodologies.

Nathalie and I as we are heading out from Seward to start our deployment.

Half of this work is the Community Near-trench Geodetic Experiment that is deploying 18 transponders across a large swath of the Aleutian trench 150° and 165°W. The instruments make up six geodetic sites that will be measured about once a year over the next four years to capture deformation associated with some of the largest earthquakes ever recorded. Our Apply-2-Sail students are writing a great blog as we progress.

The second half is a methodology experiment trying to push our deformation observations into deeper and steeper terrains. Here we are deploying a mesh geometry of transponders to test our capabilities to measure in water depths of up to 6000 m using a Wave Glider and lower frequency acoustics than for our other systems in the community sites. The mesh is also going in very steep seafloor (near the trench) where we will perform initial tests to determine repeatability with such differential water depths (and acoustic wave paths). Lastly, the Mesh, allows for lower cost observations in regions where we would like to obtain a dense field of deformation.

Scripps and Columbia crew working with the amazing folks running the Sikuliaq.

2024