ROV Jason II witnessesd the release of the hydrophone mooring as the signal was sent from the ship to the release device pictured on the left. In the next instance, the hydrophone mooring was released to the surface and only bubbles from the wake remained (right image).
It's a relief to get the hydrophone back after not knowing if it survived the landslide. It will be a few weeks before the data are examined and analyzed, but it surely will be a fascinating record because it can tell us when the landslide occurred and how it was related to NW Rota's eruptive activity. This is probably the first ever near-field recording of a landslide on a submarine volcano, and it will help us better understand a lot of what we are seeing on the bottom this year with Jason.
The actual hydrophone instrument was pulled on board the R/V Kilo Moana after being released from the ocean floor. The hydrophone should contain data documenting the landslide event.
-Bill Chadwick, Oregon State University.