Richard Fiske is internationally known for his work with volcanoes; in certain circles in Japan he is a legend. For several years this Smithsonian geologist has been studying undersea explosive volcanoes with Japanese marine scientists. Japan is intensely concerned with the phenomenon, since it depends so much on the sea. There is also the possibility that an undersea volcano might erupt catastrophically, though that hasn't happened for thousands of years. To say the least, the tidal waves caused by such an eruption would be devastating for this island nation.

For much of this decade, Fiske has been at it, going down in a tiny Japanese submersible to explore recently active submarine craters. It's dark down there at 4,500 feet. The only lights are the sub's own beacons. The only sounds are the whirring of the video cameras and the rattle of things from the ocean floor being grabbed up by the sub's metal arm and dropped into a basket on its front.

"I've set two records," Fiske told me. "I was the tallest person ever to go into the submersible, and the oldest." He is 6 feet 1 and a bit, which is, of course, a lot more notable in Japan than here, and when he last went down, a year ago, he was 64, which is notable only when you understand that retirement at 60 is enforced in most Japanese universities. "I had to get in there like a wet noodle and scrunch up," Fiske remarked. "But I'd do it again in a minute."

All right, so why undersea volcanoes? There are plenty in the open air. "Japan is one of the best places to study explosive submarine volcanoes. For some time people didn't recognize that they even existed. We didn't know they were there unless they happened to erupt." For Fiske, and the Japanese, too, the most fascinating part is the fabulous deposits of metal-bearing minerals left by these eruptions. "We're talking about five or ten cubic miles of debris. I mean, these eruptions can be big."

Many ore deposits are formed from submarine volcanoes. The point is, on land vast amounts of valuable minerals are ejected by volcanic eruptions, only to be carried away by the wind. "But in an undersea eruption, these emanations hit cold seawater and are precipitated. They end up as mineral deposits on the ocean floor." And that also has the attention of the Japanese, although there are no immediate plans to mine the deposits.

"Volcanoes attract attention," Fiske says. "They show clearly that this earth of ours is alive, and not just sitting there like the everlasting hills. Volcanoes grow and do all kinds of interesting things." Interesting: that would be the word for Kilauea, the Hawaiian volcano that has been erupting continually since January 1983. Fiske spends a lot of time in Hawaii; he has been going there for 30 years. "We rappel deep into cracks looking for layers of ash between lava flows. They are an indicator of how Kilauea has been breaking apart over the last 1,000 years.

"As we speak, lava is pouring into the ocean, building new land. What I'm concentrating on is the fact that the volcano's magma is actually pushing its south flank into the sea."

The area being pushed aside at a rate of some 10 to 15 centimeters a year--geologically comparable to the speed of light--forms a gigantic rectangle, 50 miles across and three miles thick. "We're studying how the volcano is doing this and what the evidence is for its rates of motion in the past. The south flank of Kilauea, as it detaches, leaves cracks and faults, and we study these."

If this entire south side of the mountain ever slides off into the Pacific, "it would be truly apocalyptic. There might be tidal waves hundreds of feet high; every coastal community in Hawaii would be at risk."

Something like it has happened already: hundreds of thousands of years ago the eastern half of Oahu broke off and parts of it slid 200 miles across the ocean floor. It must have been a disaster of biblical proportions.

Fiske has never seen a volcano aborning, like Paricutín, which in 1943 grew out of a Mexican farmer's cornfield much to the farmer's irritation. But he has seen a lot of sudden activity. He has been lucky, too. "I was in a helicopter crash in the eastern Caribbean, which I regard as a close call. The helicopter was destroyed. I was so thoroughly strapped in that I wouldn't have made it out if the fuel tank had exploded. Other than that I've never been endangered by working on volcanoes." A number of Fiske's colleagues and friends have been killed, including the famous French husband-wife team of volcano cinematographers, Maurice and Katia Krafft, who traveled the world filming eruptions. "I met them 30 years ago and got to know them very well. They were good friends of the Smithsonian's Global Volcanism Program and were also good personal friends. Wonderful people. Very gregarious. They were serious volcanologists and knew the dangers--they just became a little too careless. In 1991 while filming a Japanese volcano called Unzen, they and 40 others were caught in an avalanche of ash and hot gas. Gas masks or fire suits wouldn't have protected them. They were just too close at the wrong time. It would be an awful death--being baked in the extreme heat. Generally, you can move out of the way in time. Lava flows slowly. But an explosion or an avalanche of hot gas can engulf you in an instant."

When we met, Fiske was mourning the tragedy on Montserrat in the Caribbean. "The southern two-thirds of the island is just devastated, everybody's left, 20 or so people killed and no end in sight. This can go on for two or three years. It's terrible: people have lost their property, their houses; people are still paying mortgages on property covered by ash." Everything was covered by inches and feet of gray mud, the result of dozens of pyroclastic flows. Buildings were buried to the rooftops.

Fiske got into his work by luck: he had an uncle who was a geologist for an oil company in Venezuela, and at age 10 he decided to do the same. "As a kid growing up in Baltimore it seemed really romantic." For a while he had summer jobs for oil firms. Petroleum geologists lead fairly eventful lives. Lots of travel.

But there was more than that. While getting his doctorate at Johns Hopkins, Fiske joined forces with two of his favorite professors studying Mount Rainier. Like Mount St. Helens, Rainier will doubtless erupt in the future (Smithsonian, July 1996) and could send an enormous river of mud and debris, called a "lahar," straight down upon densely populated areas. From then on, for Dick Fiske, it was volcanoes.

I forgot to mention that Fiske was the director of the National Museum of Natural History for five years. "I enjoyed most of it but yearned to get back to research. Mount St. Helens erupted while I was director. It pained me not to be scientifically involved." Fiske had a major role in organizing the museum's magnificent new Janet Annenberg Hooker Hall of Geology, Gems and Minerals, including its dramatic Plate Tectonics Gallery. He was also chief curator for the Smithsonian Institution Traveling Exhibition Service show "Inside Active Volcanoes" and spearheaded a video production, Inside Hawaiian Volcanoes. "It's a splendid video, produced and directed by Maurice Krafft," Fiske noted. "It's for sale down in the shop and by mail order."

"I do like the fieldwork best, though," he said. "I sometimes take my family to Hawaii on vacations, but when I'm there to work there's little time for anything else. Once you get started in volcanoes you become a junkie, I guess. The earth is always changing, and you're trying to outfox it, understand its past activity and predict what it's likely to do in the future. Volcanoes are exciting, and for me they have made for a wonderfully fulfilling career."

By Michael Kernan