Kuno, Hisashi

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KUNO, HISASHI

(b. Tokyo, Japan, 7 January1910; d. Tokyo, 6 August 1969)

petrology.

The eldest son of Kamenosuke Kuno, a japanese painter, and Tome, his wife, young Kuno went to Sendai to study at the second High School, where he was very interested in geology but spent most of the time mountain climbing and skiing. In 1929 he enrolled at the Geological Institute of the Uni versity of Tokyo. Under the influence of Professor S. Tsuboi, he decided to concentrate on petrology, and he began his career by studying the Petrology of the Izu-Hakone region.

Kuno intensively investigated the crystallization of pyroxenes from magmas and the genesis of basaltic magmas, subjects that were widely discussed in the 1930’s. “Pertrological Notes on some Pyroxene An desites from Hakone Volcano” was outstanding among his earlier papers in that it showed his re markable ability in field petrology and microscopic observations. Indeed, high-precision optical data of rock-forming minerals were Kuno’s hallmark. Recrecognizing the importance of groundmass minerals, he proceeded to establish the crystallization course of pyroxenes from magmas. The map of Hakone Volcano, appened to Kuno’s dissertation (1950a), has remained one of the best geologic maps of vol canoes in japan.

In 1939 he was appointed associate professor, but he was drafted in1941 and was in military service in northeastern china for most of World War II. After this difficult time he returned to academic life in 1946 and completed his doctoral dis sertation, “Petrology of Hakone Volcano and the Adjacent Areas, Japan,” which was published in 1950. Here Kuno elucidated the genesis of two groups of andesites and the role of pyroxenes. With this paper he established his international reputation as a petrologist. During 1951 and 1952 he was invited to study pyroxenes at Princeton Univesity by a grant of the Geological Society of America. At Princeton he collaborated with H. H. Hess, who became his lifelong friend.

For his petrological study of pyroxenes Kuno was awarded the Japan Academy Prize in 1954. His book Volcanoes and Volcanic Rocks (1954) was well received as a standard textbook. In 1955 he was promoted to professor of petrology at the Uni versity of Tokyo, a position he held until his death. In “Differentiation of Hawaiian Magmas,” based on observations in Hawaii, he showed the possibility of generating granitic magma from tholeiitic magma through fractional crystallization, and also that the depth where partial melting of peridotite occurs in the upper mantle determines whether tholeiite or alkali olivine based magma is produced.

Extending this view to the Japanese islands, Kuno found a close correlation between the depths of earthquake focuses and the distribution of various basaltics rocks and presented a hypothesis that tho leiite magma is produced at depths of less than 200 kilometers and alkali olivine basalt magma at depths greater than 200 kilometers. With additional petro chemical data he later added high-alumina basalt magma, intermediate between the two magmas in composition and formed at an intermediate depth, as the third primary magma. This model provoked much interest among experimental petrologists, and Yoder and Tilley, Ringwood and Green, Kennedy, and later Kushiro made various experiments at high temperatures and pressures on artificial systems containing olivine, pyroxene, and natural rocks, most of which supported kuno’s model. Thus Kuno made a great contribution to experimental petrology, although he himself approached the problem mainly from the viewpoint of a field petrologist.

In the field of volcanology he wrote many papers on calderas, volcanic eruptions based on the pyroclastic materials, and the origins of andesites and petrographic provinces. His paper “Origin of Cenozoic Petrographic provinces of Japan and Surrounding Areas” greatly influenced petrogenetic discussions, in his later years Kuno was interested in the petrology of the moon and was registered with NASA as a principle investigator on the returned lunar samples. It is a great pity that he died of cancer shortly before the lunar rocks from Apollo 11 were available for investigation.

Kuno trained many excellent petrologists, among them A. Miyashiro, Y. Seki, s. Aramaki, and I. Kushiro. His activitieis in academic societies were numerous; among his many honors, he was honorary fellow, Geological Society of America and Mineralogical Society of America; honorary member, Geological Society of London; foreign associate, National Academy of Sciences; president, Volcanological Society of Japan, Geological Society of Japan, and international Association of Volcanology and Chemistry of the Earth’s Interior; and vice president, International union of Geodesy and Geophysics. He was survived by his wife, kimiko, his son, Takashi, and his daughter, shizuko.

BIBLIOGRAPHY

I. Original Works. “On the ‘Pyroxene Andesites’ from Japan,” in Bulletin of the Volcanological Society of Japan, 1 (1932), 20–37; “petrological Notes on Some Pyroxene Andesites from Hakone Volcano, with Special Reference to Some Types with Pigeonite Phenocrysts,” in Japanese Journal of Geology and Geography, 13 (1936), 107–140; “Fractional Crystallization of Basaltic Magmas,” ibid., 14 (1973), 189–208; “Geology of Hakone Volcano and Adjacent Areas, parts I and II,” in Journal of the Faculty of science, University of Tokyo, 7 (1950a), 257– 279, 351–402. “Petrology of Hakone Volcano and the Adjacent Areas, Japan,” in Bulletin of the Geological Society of America, 61 (1950b), 975–1019; “Formation of Calderas and Magmatic Evolution” in Transactions, American Geophysical Union, 34 (1953), 267–280; Iwanami Zensho (“Volcanoes and Volcanic Rocks,” Tokyo, 1954); “Differentiation of Hawaiian Magmas,” in Japanese Journal of Geology and Geography, 28 (1957), 179–218, written with K. Yamasaki, C. Iida, and K. Nagashima.

“Origin of Cenozoic petrographic provinces of Japan and Surroundings Areas,” in Bulletin volcanologique, 2nd ser., 20 (1959), 37–76; “High-alumina Basalt,” in Journal of Petrology, 1 (1960), 121–145; “Origin of Primary Basalt Magmas and Classification of Basaltic Rocks,” ibid., 4 (1963), 75–89; “Lateral Variation of Basalt Magma Type Across Continental Margins and Island Ares,” in Bulletin volcanologique. 2nd ser., 29 (1966), 195–222; “Volcanological and petrological Evidences Regarding the Nature of the Upper Mantle.”in T. F. Gaskell, ed., The Earth’s Mantle (London, 1967), 89–110; “Differentiation of Basalt Magmas,” in H. H.Hess and A. Poldervaart, eds., Basalts: The Poldervaart Treatise on Rocks of Basaltic Composition, II (New York, 1968), 623–688; “pigeonite-bearing Andesite and Associated Decite from Asio, Japan,” in American journal of Science, 267A (1969), 257–268; Selected Papers by professor Hisashi Kuno (Tokyo, 1969).

II. Secondary Literature. Memorials were written by H. L. Foster in Geological Society of America: Memorials, I (1973), 27–37, and K. Yagi in American Mineralogist, 55 (1970), 573–583; both contain bibliographies. See also K. yagi, “Life and Works of Professor Hisashi Kuno,” in Journal of the Japanese Association of Mineralogists, Petrologists, and Economic Geologists, 63 (1970), 30–42.

Kenzo Yagi