Bruce Marsh / Bruce Marsh is a geophyisics professor at Johns Hopkins University who has traveled the globe to study magma dynamics. It’s earned him a catalogue of unbelievable expedition adventures and the nickname Magma P.I., but only recently did he encounter what he says represents the most exciting magmatic interaction of his life: the accidental discovery of an underground chamber on the Big Island that allows, for the first time ever, the study of magma before it breaches the earth’s surface.

So, tell me about the drilling project and how this chamber was discovered.

It’s pretty funny, the turns that science takes. This company, Ormat, [was] just doing routine drilling … They drilled down to a distance of one and a half miles and they encountered live magma. They had a consulting geologist, and he realized what this was and he went to talk to various people and tried to get them interested in it. They thought it was interesting, but no one was really enthusiastic. They just wanted to know what it was and what they could expect. He kept trying to find people who would be interested. I had just come back from Antarctica and I looked at this e-mail from this fellow who I didn’t know and I printed it out and brought it to my PhD students and we started doing calculations immediately. It’s the first subsurface magma that’s ever been found. It’s exceptional. You may not think it’s unusual to find it in Hawai’i, but it is. On top of it all, it’s not basaltic magma like you find everywhere in Hawai’i, but this is the material that continents are made from. So we have caught the magma in its natural habitat. We have never really been able to see it in real time when the magma is alive and active.

For people like me, who studied magma their whole lives, this is the Jurassic Park of magma. It’s spectacular. Everybody gains. It’s pure science, it has applications in energy for the people in Hawai’i and in engineering. There’s a real possibility we could do further drilling to see how big it is and watch it over time. If we get money from the National Science Foundation we can use their drilling rig. And drilling these holes is expensive. They spent $6-8 million on this.

You mentioned it’s not basaltic magma and I understand it’s actually dacite. What’s unique about this kind of magma?

Dacite is a silica, [the stuff we] make wine goblets and window glass out of. For comparison, basalts are made up by 50 percent of silica. Then you have granite like what you’d make into countertops, that’s more like 70-75 percent. And then this stuff is 67-68 percent. It’s very refined and really distinctive. It’s interesting. This is the kind of material that once it cools, it just becomes a solid rock. We’re used to looking into deep valleys, eroded valleys for this stuff. I work a lot in Antarctica, but here there’s no ice and snow and we can look down deep and see what the Hawaiian plumbing system is like. The active plumbing system in Hawai’i is what was perhaps in Antarctica a long time ago. We can draw the connection but working in Antarctica is nothing like looking at a real, active system. Even when we see lava and volcanoes, we don’t really know what it’s like inside. It’s like, imagine in the study of the human body. You see blood come out but you don’t know anything of what it’s like inside. You’re not allowed to go inside so you use needles and probes. This allows us to put the whole system together. I’ve spent my whole career looking at volcanoes … to suddenly see this live system? Oh my gracious, this is fantastic.

That is intense. How hot is magma?

It’s almost 2,000 degrees Farenheit.

So how does the drilling equipment not melt?

They have relatively cool drilling fluids they shoot down. Then they drilled into this chamber and it started to grab and stick the drilling rig. The accomplished drillers pulled it up a bit and waited. And the hole filled up. It was glassy. They pulled and this glass came up in pieces. It kind of grinds its way down and pieces of it came up and they said, “My goodness, this is glass from what was liquid magma.” They did this three times and it kept happening.

I’m still struck by the comparisons you drew between Hawai’i and Antarctica and their similar trajectories over different periods of time–albeit vastly distant geologic periods of time.

Well what’s interesting about the Hawaiian Islands, we know there’s a plumbing structure that connects them. You’re on O’ahu right now and O’ahu doesn’t have any active volcanism, but 4 or 5 million years ago, it did. Now it’s all happening on the Big Island. And there is a new island being built now that’s 2.5 thousand feet down and there are eruptions on the seafloor. So eventually, if it wasn’t for the ocean, we could just look down into it. So what we’re looking at now, in terms of the kind of science, it’s like being able to cut a car engine in half. In the old days, Ford Motor Company would slice an engine right down the middle. We’re still at the stage where we have to look at old volcanic systems to figure out new ones. Back to Antarctica: it has a deeply eroded magmatic system. We can actually see the form of it, the shape of it, how it was interconnected. Now that’s one link but it’s a dead link. We then have the active parts of the earth. Now, through this drilling, we have an active magma to study. Now we can say what fits in perfectly with what we have studied of the past. It’s a critical missing piece.

What else have you gleaned from your time working here so far?

In Hawai’i we see the big volcanoes like Kl-lauea, Mauna Loa,and so on. We see earthquakes and eruptions and we infer wants happening. It’s spectacular, but for geologists, it’s like taking books out of the library and ripping out pages and scattering them: so we see the things that shot out but we don’t know how they were inside the system. This discovery allows us to see a plumbing system that you can then compare them to the lavas that would be on the surface. You spend so much time wondering what a real active system would be like at depth and now here’s one, not only can we see it, but it’s quite interesting and it’s in its natural habitat.

How do you know it’s not going to explode or erupt or respond in some way to the drilling?

Well we already drilled into it and it turns out it’s very dry. So instead of forming big bubbles–like say you had a soda that you shake up and it would froth out–it didn’t froth at all. This magma is very dry and it’s very safe.

So what’s the next step? There must be so much you want to learn from this discovery.

Oh, yes. We are trying to gather enough momentum and interest throughout the scientific community to possibly drill some more holes. The advantages are clear: We get science, we get power, we get technical background on drilling close to magma. It’s interesting, too, how this helps the public understand that geologists and engineers and power people all work together to make advances.

How do you monitor under the surface?

You can go down because you send probes down there. They measure temperature, pressure and you can bring up samples that come up like glass. Down there, at that temperature, it’s yellow-hot. You look in your toaster or your hairdryer–those red squiggly lines you see–that’s only 500 degrees Centigrade. Double that and it’s this orange, yellow-hot. As you cool it, it turns into a colorless glass with tiny crystals in it. We can even study tiny samples of the crystals and it’s really interesting.

What’s the most fascinating thing about your line of work?

I’ve been everywhere in the world. I’ve been on volcanoes for small eruptions. I’ve been chased by brown bears, gone underwater in Iceland, I got malaria in Africa. I’ve been everywhere and I’ve done everything. I’m very lucky I’m even alive. I’ve turned out 27 PhD students and it’s terrific seeing them work. But, really, the only place I have left to work is the South Pole.

And somewhere along the way people started calling you Magma P.I.?

Yeah, someone gave me that nickname and it just stuck. It works even more perfectly for me in Hawai’i. But I have to say, I don’t get the money Tom Selleck gets. Or the girls.

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