Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-27T07:03:25.815Z Has data issue: false hasContentIssue false
  • English
  • Français

Ilvaite from a serpentinized peridotite in the Asama igneous complex, Mikabu greenstone belt, Sambagawa metamorphic terrain, central Japan

Published online by Cambridge University Press:  05 July 2018

Takashi Agata  and
Mamoru Adachi
Takashi Agata
Affiliation:
Department of Earth and Planetary Sciences, Nagoya University, Nagoya, 464-01 Japan
Mamoru Adachi
Affiliation:
Department of Earth and Planetary Sciences, Nagoya University, Nagoya, 464-01 Japan
Get access Rights & Permissions [Opens in a new window]

Abstract

Ilvaite is sparsely disseminated in a serpentinized plagioclase wehrlite of the Asama igneous complex that underwent the Sambagawa regional metamorphism of pumpellyite-actinolite to greenschist facies. Ilvaite in the Asama complex is monoclinic (a = 13.019(5), b = 8.808(2), c = 5.850(4) Å, β = 90.19(4)°), and its composition is similar to the ideal end-member composition (). Ilvaite occurs in mats of serpentine (chrysotile); it probably formed during serpentinization, which might have accompanied the Sambagawa metamorphism. The associated secondary minerals include salitic clinopyroxene, magnetite and andradite. The ilvaite-free mineral assemblage that formed during the serpentinization is usually serpentine-clinopyroxene-magnetite, which is widespread in the complex. The phase relations between coexisting minerals suggest that the conditions during the formation of the ilvaite-bearing assemblage were reducing when compared to those of the assemblage serpentine-clinopyroxene-magnetite. The reducing conditions during the ilvaite formation were presumably brought about by hydrogen gas that1 was generated during the serpentinization of olivine.

Keywords

ilvaiteserpentinizationreducing conditionsAsama igneous complexMikabu greenstone beltSambagawa metamorphism
Type
Mineralogy
Information
Mineralogical Magazine , Volume 59 , Issue 396 , September 1995 , pp. 489 - 496
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1995

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Agata, T. (1989) Asama layered igneous complex, Mikabu greenstone belt, central Japan. DELP (Dynamics and Evolution of Lithosphere Project) Pub. 28, 83–4.Google Scholar
Agata, T. (1994) The Asama igneous complex, central Japan: an Ultramafic-mafic layered intrusion in the Mikabu greenstone belt, Sambagwa metamorphic terrain, central Japan. Lithos, 33, 241–63.CrossRefGoogle Scholar
Banno, Y. (1992) Blueschists in serpentinite conglomerates associated with the Mikabu greenstones in eastern Kii peninsula, Japan. J. Petrol. Mineral. Econ. Geol, 87, 207-20 (Japanese with English abstract).CrossRefGoogle Scholar
Bartholome, P., Duchesne, J.C. and Plas, L. (1968) Sur une forme monoclinique de l'ilvaite. Ann. Soc. Geol. Belgique, 90, 779–88.Google Scholar
Barton, M. and Bergen, M.J. (1984) Secondary ilvaite in a dolerite dyke from Rogaland, SW Norway. Mineral. Mag., 48, 449–56.CrossRefGoogle Scholar
Buddington, A.F. and Linsley, D.H. (1964) Iron-titanium oxide minerals and synthetic equivalents. J. Petrol, 5, 310–57.CrossRefGoogle Scholar
Burt, D.M. (1971) The facies of some Ca-Fe-Si skarns in Japan. Carnegie Inst. Washington Yearb., 70, 185–8.Google Scholar
Conveney, R.M. Jr., Goebel, E.D., Zeller, E.J., Dreschhoff, G.A.M. and Angino, E.E. (1987) Serpentinization and the origin of hydrogen gas in Kansas. A.A.P.G. Bull, 71, 39–48.Google Scholar
Dietrich, V. (1972) Ilvait, Ferroantigorit und Greenalith als Begleter oxidisch-sulgidischer Vererzungen in den Oberhalbsteiner Serpentiniten. Schweiz. Mineral. Petrogr. Mitt., 52, 57–74.Google Scholar
Finger, L.W. and Hazen, R.M. (1987) Crystal structure of monoclinic ilvaite and the nature of the monoclinic-orthorhombic transition at high pressure. Zeit. Krist., 179, 415–30.CrossRefGoogle Scholar
Graeser, S. (1975) Ilvait als alpines Zerrkluft-Mineral. Schweiz. Mineral. Petrogr. Mitt., 55, 1–7.Google Scholar
Gustafson, W.I. (1974) The stability of andradite, hedenbergite, and related minerals in the system Ca-Fe-Si-O-H. J. Petrol., 15, 455–96.CrossRefGoogle Scholar
Lucchetti, G. (1989) High-pressure ilvaite-bearing mineral assemblages from the Voltri group (Italy). Neues Jahrb. Mineral. Mh., 1-7.Google Scholar
Mouri, K. and Enami, M. (1988) Chemical compositions of minerals from the Kichijosan and Joyama complexes in the Sanbagawa metamorphic belt, central Japan. Bull. Nagoya Univ. Museum, 4, 15–30 (Japanese with English abstract).Google Scholar
Nakamura, Y. (1971) Petrology of the Toba ultrabasic complex, Mie Prefecture, central Japan. J. Fac. Sci. Univ. Tokyo Ser. II, 18, 1–51.Google Scholar
Naslund, H.R., Hughes, M. and Birnie, R.W. (1983) Ilvaite, an alteration product replacing olivine in the Skaergaard intrusion. Amer. Mineral., 68, 1004–8.Google Scholar
Neal, C. and Stranger, G. (1983) Hydrogen generation from mantle source rocks in Oman. Earth Planet. Sci. Lett., 66, 315–20.CrossRefGoogle Scholar
Onuki, H., Akasaka, M., Yoshida, T. and Nedachi, M. (1982) Ti-rich hydroandradites from the Sanbagawa metamorphic rocks of the Shibukawa area, central Japan. Contrib. Mineral. Petrol., 80, 183–8.CrossRefGoogle Scholar
Powder Diffraction File, Set 11-15 (1972) Joint Committee on Powder Diffraction Standards. Powell, R. and Powell, M. (1977) Geothermometry and oxygen barometry using coexisting iron-titan oxides: a reappraisal. Mineral. Mag., 41, 257–63.CrossRefGoogle Scholar
Pesquera, A. and Velasco, F. (1986) An occurrence of ilvaite layers in the Cino Villas metasomatic rocks, western Pyrenees (Spain). Mineral. Mag., 50, 653–6.CrossRefGoogle Scholar
Ramdohr, P. (1967) A widespread mineral association connected with serpentinization, with notes on some new or insufficiently defined minerals. Neues. Jahrb. Mineral. Abh., 107, 241–65.Google Scholar
Ramdohr, P. (1969) The Ore Mineral and their Intergrowths. Pergamon Press. Seki, Y., Oba, T., Mori, R. and Kuriyagawa, S. (1964) Sambagawa metamorphism in the central part of Kii peninsula. J. Japan. Assoc. Mineral. Petrol. Econ. Geoi, 52, 73–89. (in Japanese with English abstract).Google Scholar
Spencer, K.J. and Linsley, D.H. (1981) A solution model for coexisting iron-titanium oxides. Amer. Mineral., 66, 1189–201.Google Scholar
Stormer, J.C., Jr. (1983) The effect of recalculation on the estimates of temperature and oxygen fugacity from analyses of multicomponent iron-titanium oxides. Amer.MineraL, 68, 586–94.Google Scholar
Takèuchi, Y., Haga, N. and Bunno, M. (1983) X-ray study on polymorphism of ilvaite, HCaFe!+Fe3+O2[Si2O7]. Zeit. Krist., 163, 267–83.Google Scholar