Participant Interview:
Bill Chadwick
Geologist
Oregon State University/NOAA Vents Program

Jeff: How did you get interested in volcano monitoring?
Bill: In college I was a field assistant at Mt. St. Helens. We flew helicopters into the crater and there was an eruption while I was there. It totally blew my mind. I walked around in the crater and there was lots of steam and glowing cracks in the floor of the volcano. It was a blast.

Jeff: As a geologist, what are your responsibilities on this cruise?
Bill: I do a little of everything. I oversee the acoustic navigation. I'm collecting the Imagenex data (high resolution bathymetry). I'm also researching the geology of the eruption site with Bob Embley and John Chadwick (no relation). We're still working on mapping out the 1998 lava flow, especially to the south. I've also worked on the seafloor monitoring instruments, including the extensometers that measure horizontal deformation of the volcano and bottom pressure recorders that measure vertical deformation.

Jeff: Why measure deformation of the volcano?
Bill: Deformation monitoring is one of the main techniques to help geologists determine what the magma is doing underground. My research involves using volcano monitoring methods from land-based geological research at Axial volcano. It's really challenging because it's a lot harder to work on the sea floor. On land, you just drive out in your car and plop an instrument down. Out here, the ocean floor environment is unforgiving so there's many things that can go wrong.

Jeff: Why is Axial so interesting geologically?
Bill: Since it's a hot spot, it erupts frequently and has the largest magma supply on the Juan de Fuca Ridge. On the ridge itself we wouldn't see this type of inflation and deflation. So, it's a good place to try initial underwater monitoring. Axial is interesting because it might behave like some of the well known basaltic volcanoes in Iceland and Hawaii. The neat thing about the research we're doing is that 10 years ago no one had ever detected, studied, or known about a mid-ocean ridge eruption. The 1998 Axial eruption was the first time monitoring instruments recorded an eruption. It's really cool. That's where the fun comes in. You feel like your really participating in a discovery. It's really a frontier in marine science.

Bill Chadwick reviewing the 1998 lava flow map in the computer lab.

Older pillow basalt with a crinoid on top.