Mineral Sciences Staff
- Richard S. Fiske
- Geologist Emeritus - Division of Petrology and Volcanology
- Phone: (202) 633-1794
- Fax: (202) 357-2476
- E-mail Address: fisker
- Mailing Address:
PO Box 37012, MRC 119
Washington, DC 20013-7012
- Shipping Address:
National Museum of Natural History
10th & Constitution NW
Washington, DC 20560-0119
- Ph.D. Johns Hopkins University (1960)
- A big surprise at Kilauea (iTunesU)
My current research is focussed on volcanoes in Japan and Hawaii. My work is exciting and I think important. Briefly:
Japan: In collaboration with scientists of the Japan Marine Science and Technology Center (JAMSTEC), I have been studying a submarine caldera volcano, similar to the familiar Crater Lake structure in Oregon. This caldera volcano is located 400 km south of Tokyo at an ocean depth of about 1400 m. I and Japanese colleagues have made a total of 15 manned submersible dives into this volcano and have discovered the following:
- Huge volumes of lightweight pumice (literally cubic miles of it) can be erupted from submarine volcanoes, a concept heretofore denied by most volcanologists. Besides expanding our understanding of similar submarine volcanoes worldwide, our findings are sharpening the appreciation of the hazards posed by such volcanoes. Our work also has relevance to those many geologists studying ancient volcanoes of this type preserved in the geologic record. Now they have a present-day example for comparison.
- In the course of our work, we discovered a huge mass of metallic sulfides growing on the floor of the caldera. Somewhat akin to the familiar "black smokers" that occur along mid-ocean ridges, this newly-discovered mass is also fed by smokers, but in contrast these are extraordinarily rich in gold and silver. Crude estimates of the in situ value of this deposit range from $1 to 2 billion (no typo- billion!). The Japanese are currently carrying out a program of sea-floor drilling to quantify the full dimensions and metals content of the mass, and it is quite possible that the deposit will eventually be mined. I believe our work is a good example of quality basic research that has led to a discovery of great potential value.
- Our findings have been published in Science (v. 283, 1999), the Bulletin of the Geological Society of America (v. 113, 2001), and in several Japanese language journals.
Hawaii: In collaboration with the Geological Survey's Hawaiian Volcano Observatory, I and an NMNH colleague are about mid-way through a study of explosive eruptive activity at Kilauea Volcano that took place about 1200 years ago.
We have discovered abundant evidence for an explosion from this supposedly gentle volcano that hurled dense pieces of rock as large as grapefruit for distances of 10-12 km. Many of these rocks were torn from several km deep within the volcano, and we think they may have been carried to heights of 15-20 km before falling back to earth. Such events have never been imagined, much less documented, but our evidence (gathered over the past 6 years) is compelling.
Our results are expanding understandings of large shield volcanoes, and they will reveal for the first time some of the extreme hazards they can pose.
Our research is ongoing, and to date we have only published abstracts of our findings. In the near future we'll begin to prepare articles for publication in various earth science journals.
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