NOVA: Would it look like what eruptions look like today?

RHODES: Once the conduit was isolated from sea water then the kinds of eruptions that you would get would be very similar to the sort of eruptions that you see on Kilauea today with fire fountaining forming spatter and then lava flows which would gradually form a carapace over the top of the island.

NOVA: Do you have any idea how soon the island would be fit for living things?

RHODES: My guess again is that it would be very, very rapid. That you'd soon see bird life inhabiting the island. You'd very quickly get plants establishing themselves.

NOVA: That might have been the way things worked on the very first Hawaiian island.

RHODES: I would think so. Yes, I would think there'd be very quick colonization from wind-blown seeds and things being carried by birds.

NOVA: Why are you fascinated with volcanos?

RHODES: There's a certain romance to working on volcanos. There's a very high level of excitement working with volcanos and it's this opportunity, I think, to combine this level of excitement with trying to solve a geological problem. In other words, trying to figure out, how does a volcano work, what's the nature of the magma that's supplying the volcano, what does that magma tell us about the mantle plume, what happens to it when it gets into the volcano. All of these problems that I get a big kick out of, but at the same time, there's probably no more exciting place to work on earth than working on a volcano.

NOVA: Describe the first time you ever saw a volcano erupting?

RHODES: We'd taken a group of students out to Hawaii on a field trip to look at the Hawaiian volcanos and we had the good fortune of taking a three day hike over Mauna Loa just at the time when it erupted, and we were actually camping on the side of the volcano. It's about a ten thousand foot level, when it erupted that night. It was pretty exciting stuff. It was amusing really because we were staying in a little cabin at ten thousand feet and because of the crowding in the cabin I decided to sleep outside upon the top of the cone and one of my students, at about 1:30 in the morning, came running up, woke me up and said, "the volcano's erupting!" I told him not to be so bloody stupid. I wasn't going to be fooled by that one, and then I looked out of my tent and the whole sky was just orange and sure enough the volcano was erupting. So at that point we all got up and climbed up to the top of the cone and sat there drinking coffee and making observations and watching the lava flows.

NOVA: When you see something like that, what are you seeing?

RHODES: Well, you get this enormous sense of power, enormous vibration and sort of deafening noise that's going on and in addition to that of course you get the heat radiating from the lava to where you're standing.

NOVA: Are you in any danger?

RHODES: Not if you're careful.

NOVA: How can you be careful?


MR: You can get very close. You need to know which direction the wind's blowing in so that it doesn't blow the hot material over you. You need to know where, if there are fumes so don't choke in the fumes. You need to keep an eye out as to what the lava's doing, where it's flowing so you don't get cut off. And if you're walking on relatively new lava then you've got to be very careful where you tread and how you tread.

NOVA: Has anybody ever gotten injured?

RHODES: Yes, well first of all a photographer was killed in 1924, but that was when Kilauea erupted explosively. A US Geological Survey geologist was rather badly burned when the lava that he was standing on broke underneath him and his feet went into the molten lava. So he was, he was fairly badly injured. He's all right now. And then I think only a few weeks ago someone was killed on Kilauea when part of the bench of newly formed lava broke off and collapsed into the sea. That person was never seen again. But, you know, there haven't been very many deaths or very many injuries for that matter....Most lava flows move fairly slowly. See, most lava flows, you can out-run them.

NOVA: How do eruptions occur?

RHODES: Eruptions occur not only in the crater but also along the sides of the volcano, particularly in two very narrow zones which we refer to as rift zones. One of them runs down the southwest side of the volcano and the other one runs along the eastern side of the volcano and actually goes out to sea off the coast of Hawaii. We think that when the magma ascends from the mantle into the volcano that it's actually filling a reservoir located beneath the summit crater. As more magma accumulates in this reservoir, pressures on the magma reservoir begin to build such that it can no longer contain the magma. This could lead to an eruption in the summit crater, or alternatively, magma often manages to push its way through the flanks of the volcano, along one of these two rift zones, and then it may either erupt or it may not. Sometimes it can just simply push its way down the rift zone and then stop, gradually cooling and solidifying. On other occasions it will be pushing its way down the rift zone and actually break the surface and lead to an eruption.

NOVA: What's the rift zone?

RHODES: A rift zone is a very narrow region on the flanks of the volcano, typically only a few kilometers wide, two to three kilometers wide at the most, where eruptive activity has been concentrated and what you find along these rift zones are concentrations of cinder cones where previous eruptions have occurred and also cracks and fissures that have developed.