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Age (K–Ar phengite)–temperature–structure relations: a case study from the Ishigaki high-pressure schist belt, southern Ryukyu Arc, Japan

Published online by Cambridge University Press:  22 July 2008

N. D. NUONG ,
T. ITAYA  and
Y. NISHIMURA
N. D. NUONG
Affiliation:
Research Institute of Natural Sciences, Okayama University of Science, Okayama 700-0005, Japan
T. ITAYA*
Affiliation:
Research Institute of Natural Sciences, Okayama University of Science, Okayama 700-0005, Japan
Y. NISHIMURA
Affiliation:
Miyanoshimo 1648-1, Yamaguchi 753-0011, Japan
*
†Author for correspondence: [email protected]
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Abstract

The Ishigaki high-pressure schist belt in the southern Ryukyu Arc is correlated with the Suo high-pressure schist belt in southwest Japan. The former metamorphic sequence is composed mainly of basic and pelitic schists and is subdivided into three zones, the lower-grade zone A, the medium-grade zone B and the high-grade zone C, based on the mineral assemblages of the basic schists. The K–Ar phengite age gives 188–205 Ma for zone A, 196–206 Ma for zone B and 208–220 Ma for zone C, while the apparent d002 spacing of carbonaceous materials is 3.590–3.437 Å, 3.415–3.390 Å and 3.387–3.364 Å, respectively. The age–d002 relationships suggest that the ages become older with increasing metamorphic temperature. This positive age–temperature relationship in the Ishigaki area contrasts with a negative relationship in the Nishiki area in the Suo belt. The two areas also display a contrasting thermal structure with the former area having an inverted metamorphic gradient and the latter displaying a normal thermal structure. These contrasting age–temperature–structure relationships in the metamorphic belt could be due to different tectonic styles relating to the exhumation of the metamorphic sequences. We suggest that the ages obtained are related directly to the ductile deformation history of the matrix phengite below the closure temperature (500°C) during exhumation of the host rocks. The duration from the beginning of exhumation to the apparent resetting of the phengite K–Ar system was different between the two metamorphic sequences, and significantly longer in the Ishigaki than the Nishiki.

Keywords

Suo metamorphic beltIshigaki high-pressure schistsK-Ar phengite aged002 spacing of carbonaceous materialsductile deformationexhumation tectonicsage-temperature-structure relations
Type
Original Article
Information
Geological Magazine , Volume 145 , Issue 5 , September 2008 , pp. 677 - 684
Copyright
Copyright © Cambridge University Press 2008

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References

Aoya, M., Uehara, S., Matsumoto, M., Wallis, S. R. & Enami, M. 2003. Subduction-stage pressure–temperature path of eclogite from the Sambagawa belt: Prophetic record for oceanic-ridge subduction. Geology 31, 1045–8.CrossRefGoogle Scholar
Arnaud, N. O. & Kelley, S. 1995. Evidence for excess Ar during high pressure metamorphism in the Dora Maira (western Alps, Italy), using a Ultra-Violet Laser Ablation Microprobe 40Ar–39Ar technique. Contributions to Mineralogy and Petrology 121, 1–11.CrossRefGoogle Scholar
Carlson, S. D. 1983. The polymorphs of CaCO3 and the aragonite–calcite transformation. In Carbonates: Mineralogy and Chemistry (ed. Reeder, R. I.), pp. 191–225. Reviews in Mineralogy and Geochemistry 11. Mineralogical Society of America.CrossRefGoogle Scholar
Chopin, C. 1984. Coesite and pure pyrope in high-grade blueschists of the western Alps; A first record and some consequences. Contributions to Mineralogy and Petrology 86, 107–18.CrossRefGoogle Scholar
De Jong, K., Féraud, G., Ruffet, G., Amouric, M. & Wijbrans, J. R. 2001. Excess argon incorporation in phengite of the Mulhacén Complex: submicroscopic illitization and fluid ingress during late Miocene extension in the Betic Zone, south-eastern Spain. Chemical Geology 178, 159–95.CrossRefGoogle Scholar
Dodson, M. H. 1973. Closure temperature in cooling geochronological and petrological systems. Contributions to Mineralogy and Petrology 40, 259–74.CrossRefGoogle Scholar
Dodson, M. H. & McClelland-Brown, E. 1985. Isotopic and paleomagnetic evidence for rates of cooling, uplift and erosion. In The chronology of the geological record (ed. Snelling, N. L.), pp. 315–25. Geological Society of London, Memoir no. 10. Oxford: Blackwell.Google Scholar
Engebreston, D., Cox, A. & Gordon, R. G. 1985. Relative plate motions between oceanic and continental plates in the Pacific basin. Geological Society of America, Special Paper 206, 1–59.CrossRefGoogle Scholar
Faure, M. 1983. Eastward ductile shear during the early tectonic phase in the Sanbagawa belt. Journal of Geological Society of Japan 89, 319–29.Google Scholar
Faure, M., Monie, P. & Fabbri, O. 1988. Microtectonics and Ar–Ar dating of high pressure metamorphic rocks of the south Ryukyu Arc and their bearings on the pre-Eocene geodynamic evolution of Eastern Asia. Tectonophysics 156, 133–43.CrossRefGoogle Scholar
Giorgis, D., Cosca, M. & Li, S. 2000. Distribution and significance of extraneous argon in UHP eclogite (Suru terrain, China): insight from in situ 40Ar/39Ar UV laser ablation analysis. Earth and Planetary Science Letters 181, 605–15.CrossRefGoogle Scholar
Gouzu, C., Itaya, T., Hyodo, H. & Ahmad, T. 2006 a. Cretaceous isochron ages from K–Ar and Ar–Ar dating of eclogitic rocks in the Tso Morari complex, western Himalaya, India. Gondwana Research 9, 426–40.CrossRefGoogle Scholar
Gouzu, C., Itaya, T., Hyodo, H. & Matsuda, T. 2006 b. Excess 40Ar-free phengite in ultrahigh-pressure metamorphic rocks from the Lago di Cignana area, Western Alps. Lithos 92, 418–30.CrossRefGoogle Scholar
Hurford, A. J. 1986. Cooling and uplift patterns in the Lepontine Alps, south central Switzerland and an age of vertical movement on the Insubric line. Contributions to Mineralogy and Petrology 92, 413–27.CrossRefGoogle Scholar
Inger, S., Ramsbotham, W., Cliff, R. A. & Rex, D. C. 1996. Metamorphic evolution of the Sesia-Lanzo zone, Western Alps: time constraints from multi-system geochronology. Contributions to Mineralogy and Petrology 126, 152–68.CrossRefGoogle Scholar
Ishizuka, H. & Imaizumi, M. 1988. Metamorphic aragonite from the Yaeyama metamorphic rocks on Ishigaki-jima, southwest Ryukyu Islands. Journal of the Geological Society of Japan 94, 719–22.Google Scholar
Isozaki, Y. & Nishimura, Y. 1989. Fusaki Formation, Jurassic subduction–accretion complex on Ishigaki Island, southern Ryukyus and its geological implication to Late Mesozoic convergent margin of East Asia. Memoir of Geological Society of Japan 33, 259–75.Google Scholar
Itaya, T. 1981. Carbonaceous material in pelitic schists of the Sanbagawa metamorphic belt in central Shikoku, Japan. Lithos 14, 215–24.CrossRefGoogle Scholar
Itaya, T. & Fujino, M. 1999. K–Ar age–chemistry–fabric relations of phengite from the Sanbagawa high-pressure schists, Japan. Island Arc 8, 523–36.CrossRefGoogle Scholar
Itaya, T., Hyodo, H. & Fukui, S. 1993. Numerical experiment for recovery of reversed thermal structure in arc-trench system: New constraints on orogenic process. Memoirs of the Geological Society of Japan 42, 351–67.Google Scholar
Itaya, T., Nagao, K., Inoue, K., Honjou, Y., Okada, T. & Ogata, A. 1991. Argon isotopic analysis by a newly developed mass spectrometric system for K–Ar dating. Mineralogical Journal 15, 203–21.CrossRefGoogle Scholar
Itaya, T. & Takasugi, H. 1988. Muscovite K–Ar ages of the Sanbagawa schists, Japan, and argon depletion during cooling and deformation. Contributions to Minelorogy and Petrology 100, 281–90.CrossRefGoogle Scholar
Kaneko, Y., Kawano, Y. & Kaneko, N. 2004. An introduction of geological map of Japan 1:50,000, Ishigakijima–Thohokubu. Chishitsu News 598, 68–71.Google Scholar
Kinoshita, O. 1995. Migration of igneous activies related to ridge subduction in southwest Japan and the East Asian continental margin from the Mesozoic to the Paleogene. Tectonophysics 245, 25–35.CrossRefGoogle Scholar
Li, S., Wang, S., Chen, Y., Liu, D., Qiu, J., Zhou, H. & Zhang, Z. 1994. Excess argon in phengite from eclogite: evidence from dating of eclogite minerals by Sm–Nd, Rb–Sr and 40Ar/39Ar methods. Chemical Geology 112, 343–50.CrossRefGoogle Scholar
Maruyama, S. 1997. Pacific type orogeny revisited: Miyashiro-type orogeny proposed. Island Arc 6, 91–120.CrossRefGoogle Scholar
Miyashita, A. & Itaya, T. 2002. K–Ar age and chemistry of phengite from the Sanbagawa schists in the Kanto Mountains, Central Japan, and their implication for exhumation tectonics. Gondwana Research 5, 837–48.CrossRefGoogle Scholar
Nagao, K., Nishido, H., Itaya, T. & Ogata, K. 1984. K–Ar age determination method. Bulletin of Hiruzen Research Institute 9, 19–38.Google Scholar
Nakajima, T., Shirahase, T. & Shibata, K. 1990. Along-arc lateral variation of Rb–Sr and K–Ar ages of Cretaceous granitic rocks in Southwest Japan. Contributions to Mineralogy and Petrology 104, 381–9.CrossRefGoogle Scholar
Nishimura, Y. 1998. Geotectonic subdivision and areal extent of the Sangun belt, Inner Zone of Southwest Japan. Journal of Metamorphic Geology 16, 129–40.Google Scholar
Nishimura, Y., Coombs, D. S., Landis, C. A. & Itaya, T. 2000. Continuous metamorphic gradient documented by graphitization and K–Ar age, southeast Otago, New Zealand. American Mineralogist 85, 1625–36.CrossRefGoogle Scholar
Nishimura, Y., Itaya, T., Isozaki, Y. & Kameya, A. 1989. Depositional age and metamorphic history of 220 Ma high P/T type metamorphic rocks: an example of the Nishiki-cho area, Yamaguchi Prefecture, Southwest Japan. Memoirs of Geological Society of Japan 33, 143–66.Google Scholar
Nishimura, Y., Matsubara, Y. & Nakamura, E. 1983. Zonation and K–Ar ages of the Yaeyama metamorphic rocks, Ryukyu Islands. Memoirs of the Geological Society of Japan 22, 27–37.Google Scholar
Purdy, J. W. & Jäger, E. 1976. K–Ar ages on rock-forming minerals from the Central Alps. Memoirs of the Institute of Geology and Mineralogy, University of Padova 30, 31.Google Scholar
Ruffet, G., Féraud, G., Ballévre, M. & Kiénast, J. R. 1995. Plateau ages and excess argon in phengites: an 40Ar–39Ar laser probe study of Alpine micas (Sesia zone, Western Alps, northern Italy). Chemical Geology 121, 327–43.CrossRefGoogle Scholar
Ruffet, G., Gruau, G., Ballévre, M., Féraud, G. & Philippot, P. 1997. Rb–Sr and 40Ar–39Ar laser probe dating of high-pressure phengites from the Sesia zone (Western Alps): underscoring of excess argon and new age constraints on the high-pressure metamorphism. Chemical Geology 41, 1–18.CrossRefGoogle Scholar
Saxby, J. D. 1970. Technique for the isolation of kerogen in sulfide ores. Geochimica et Cosmochimica Acta 34, 1317–26.CrossRefGoogle Scholar
Scaillet, S. 1996. Exess 40Ar transport scale and mechanism in high-pressure phengites: a case study from an eclogitized metabasite of the Dora-Maira nappe, western Alps. Geochimica et Cosmochimica Acta 60, 1075–90.CrossRefGoogle Scholar
Schertl, H. P., Schreyer, W. & Chopin, C. 1991. The pyrope–coesite rocks and their country rocks at Parigi, Dora Maira Massif, Western Alps: detailed petrography, mineral chemistry and PT-path. Contributions to Mineralogy and Petrology 108, 1–21.CrossRefGoogle Scholar
Sherlock, S. C. & Arnaud, N. O. 1999. Flat plateau and impossible isochrons: Apparent 40Ar–39Ar geochronology in a high-pressure terrain. Geochimica et Cosmochimica Acta 63, 2835–8.CrossRefGoogle Scholar
Steiger, R. & Jäger, E. 1977. Subcommission on geochronology: convention on the use of decay constants in geo- and cosmo-chronology. Earth and Planetary Science Letters 36, 359–62.CrossRefGoogle Scholar
Taira, A., Katto, J., Tashiro, M., Okamura, M. & Kodama, K. 1988. The Shimanto Belt in Shikoku – Evolution of Cretaceous to Miocene accretionary prism. Modern Geology 12, 5–46.Google Scholar
Takasu, A. & Dallmeyer, R. D. 1990. 40Ar/39Ar mineral age constraints for the tectonic evolution of the Sambagawa metamorphic belt: implications for tectonic development of the Sambagawa accretionary prism. Tectonophysics 185, 111–39.CrossRefGoogle Scholar
Takeshita, H., Gouzu, C. & Itaya, T. 2004. Chemical features of white micas from the Piemonte calc-schists, western Alps and implications for K–Ar ages of metamorphism. Gondwana Research 7, 457–66.CrossRefGoogle Scholar
Takeshita, H., Shimoya, H. & Itaya, T. 1994. White mica K–Ar ages of blueschist-facies rocks from the Piemonte ‘calcschists’ in the western Italian Alps. Island Arc 3, 151–62.CrossRefGoogle Scholar
Tonarini, S., Villa, I. M., Oberli, F., Meier, M., Spencer, D. A., Pognante, U. & Ramsay, J. G. 1993. Eocene age of eclogite metamorphism in Pakistan Himalaya: implications for India–Eurasian collision. Terra Nova 5, 13–20.CrossRefGoogle Scholar
Villa, I. M. 1998. Isotopic closure. Terra Nova 10, 42–7.CrossRefGoogle Scholar
Wallis, S. R. 1990. The timing of folding and stretching in the Sanbagawa belt: the Asemigawa region, central Shikoku. Journal of Geological Society of Japan 96, 345–52.Google Scholar
Wallis, S. R., Banno, S. & Radvanec, M. 1992. Kinematics, structure and relationship to metamorphism of the east–west flow in the Sanbagawa belt, southwest Japan. Island Arc 1, 176–85.CrossRefGoogle Scholar