Free Ascent Tripod Test on the Santa Cruz Wharf

Staff from the USGS Pacific Coastal and Marine Science Center Marine Facility engineered a Free Ascent Tripod (FAT) for deployment in deep-sea environments along the Cascadia Subduction Zone. This tripod will provide scientists a prolonged, up-close look at the seabed, measuring processes such as sediment transport thousands of feet beneath the surface.

The tripod is equipped with instruments that measure deep-sea currents, turbidity, salinity, and other parameters. These data will be used to better characterize the causes of turbidity flows—rapid, sediment-laden currents moving downslope—that carry sediment from the continental shelf to the deep sea. Earthquakes are a known trigger for turbidity flows along tectonically active margins, but other causes, such as high-energy storms, can potentially send large sediment pulses cascading offshore to the deep sea, as well.