著者

越後 拓也 木股 三善

出版者

一般社団法人 日本鉱物科学会

雑誌

岩石鉱物科学 (ISSN:1345630X)

巻号頁・発行日

vol.38, no.3, pp.57-74, 2009 (Released:2009-07-23)

参考文献数

167

被引用文献数

1

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Organic minerals are natural organic compounds with both well-defined chemical composition and crystallographic properties; their occurrences show traces of the high concentration of certain organic compounds in natural environments. Thus the origin and formation process of organic minerals will lead us to understand the fate and behavior of the organic molecules in the lithosphere. This review divides organic minerals into the following two groups to discuss their contribution to new developments in mineralogy: ionic organic minerals in which organic anions and various cations are held together by ionic bonds, and molecular organic minerals in which electroneutral organic molecules are bonded by weak intermolecular interactions. This review is composed of five sections. The first section is concerned with the definition of both organic minerals and the above two groups. The second deals with crystal chemistry and geochemistry of oxalate minerals, which are the most typical ionic organic ones. In this section, the role of (H2O)0 is firstly discussed since most oxalate minerals incorporate (H2O)0 into their crystal structures. Then the phase relationships among hydrous/anhydrous calcium oxalate minerals, namely their structural hierarchy are described, owing to the fact that they are the most abundant ionic organic minerals. In addition, the weak Jahn-Teller effect in humboldtine [Fe2+(C2O4)·2H2O] is mentioned. Fe2+ ion causes octahedral distortion in the organic mineral though the effect has hardly been observed in inorganic minerals. The third describes the origin and formation process of karpatite (C24H12), which is the molecular crystal of coronene and the most typical molecular organic mineral. The fourth and last sections summarize the characteristics of organic minerals and discuss their contribution to earth science, respectively.

著者

木股 三善 西田 憲正 村上 英樹

出版者

一般社団法人 日本鉱物科学会

雑誌

鉱物学雜誌 (ISSN:04541146)

巻号頁・発行日

vol.23, no.2, pp.45-58, 1994-04-30 (Released:2009-08-11)

参考文献数

91

被引用文献数

1 1

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This paper reviews on crystal chemistry of plagioclases and geochemical roles of their megacrysts including native coppers and hydrocarbons, discussed in two parts.Part I. Structural classification of feldspar compositions can be allocated into four types; feldspar, paracelsian, hexacelsian and hollandite structures. Though the phase relation between the first and the second types has been open to question, recent probing of their isotropic temperature factors and bond-valence theory to the M-sites intensifies that feldspars are in the wide stability field from low to high temperatures under low pressures, and that high pressure and low pressure are the preference field for paracelsians. Though very common in north-east part of Japanese island and Izu-Bonin arcs, anorthite megacrysts have never been found in other districts in Japan and have been rare in world-wide occurrences. Native coppers, verified by chemical shift method of EPMA and X-ray microdiffraction, are found to be included by anorthite megacrysts from Japanese island arc and by labradorite ones from the continental margin of North America. These anorthites in the basaltic lavas are of approximately 1 to 3 cm size and often contain several corroded Mg-olivines scattering as single crytals less than a few mm long. The plagioclase megacrysts show no chemical zoning, but the anorthites with the Al/Si ordered state have partings developed in places whereas the labradorites are of the AUSi disordered structure indicative of high temperature type. Each role in their plagioclase structure establishes Mg, Fe, Al and Si cations as a few minor endmembers of CaFeSi3O8, CaMgSi3O8, AlAl3SiO8 and_??_Si4O8 for the solid solutions. Furthermore micro-inclusions of native zinc, copper and brass scattering in the red-clouded anorthite megacryst frozen by the supercooling environment could have an implication for a precusor to Kuroko deposits. Review (1) discusses both structural tolerance of plagioclases and their megacrysts including native coppers.

著者

新田 恵理子 木股 三善 星野 美保子 越後 拓也 濱崎 聡志 篠原 宏志 西田 憲正 八田 珠郎 清水 雅浩

出版者

一般社団法人 日本鉱物科学会

雑誌

岩石鉱物科学 (ISSN:1345630X)

巻号頁・発行日

vol.35, no.6, pp.270-281, 2006 (Released:2007-03-15)

参考文献数

43

被引用文献数

1

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High temperature volcanic sublimates including so-called “molybdenum blue” sampled around the high-temperature fumaroles at Iwodake volcano, Satsuma-Iwojima, Kyushu, Southwestern Japan, were characterized by X-ray powder diffraction, X-ray micro-diffraction, Raman micro-scattering, electron microprobe and X-ray photoelectron spectroscopic analyses. The identified minerals are molybdenite, sphalerite, tugarinovite, molybdite, hematite, halite, sylvite, anglesite, wulfenite, quartz, tridymite, cristbalite and potassium alum. Occurrences of both tugarinovite and molybdite are observed in Kudriavy volcano, too, and the coexistence of their minerals is characteristic of high-temperature volcanic sublimates. The molybdenite and sphalerite from Iwodake are exceedingly rich in Re (up to 0.77 wt%) and In (up to 1.69 wt%), respectively, distinguished from those of a different origin by chemical composition. The molybdenite consists of both of 3R and 2H1 polytypes. Sublimates from Iwodake and Kudriavy volcanoes are similar in mineralogy. Although the difference in the host rock arises between the Iwodake (rhyolite) and the Kudriavy (basaltic andesite) volcanoes, their volcanic gases resemble each other in F and Cl contents. This resemblance might cause the similarity in sublimate mineralogy between these volcanoes.

著者

龍 徹 木股 三善 西田 憲正 興野 純 清水 雅浩

出版者

一般社団法人 日本鉱物科学会

雑誌

岩石鉱物科学 (ISSN:1345630X)

巻号頁・発行日

vol.34, no.5, pp.242-251, 2005 (Released:2005-10-18)

参考文献数

27

被引用文献数

2 2

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Chemical evolution of ferrocolumbites from the Ishikawa-yama granitic pegmatites, Fukushima, Japan, has been revealed by electron microprobe analysis. The compositions of ferrocolumbites are different among sample locations, which are within about 1 km distant from each other. Three discernible trends in compositional variations in ferrocolumbites have been observed: (1) a homogeneous crystal trend, with low Ta/(Ta + Nb); (2) a trend with oscillatory zoning related to Ta and Nb; (3) a trend with patchy zoning related to Fe and Mn. Oscillatory zoning of ferrocolumbite is intimately related to crystal growth in magmatic process. Ferrocolumbite with patchy zoning shows parallel extinction and doesn’t appear to have the complementary distribution of octahedral cations due to some coupled substitutions on the plots of partition coefficient (each zone/the assumed average) against ionic radius. These facts and the curved boundaries of patchy zoning suggest that patchy zoning of ferrocolumbite has been produced by topotaxy in the open system.

著者

村上 英樹 木股 三善 下田 右 伊藤 英司 佐々木 聡

出版者

日本岩石鉱物鉱床学会

雑誌

岩鉱 (ISSN:09149783)

巻号頁・発行日

vol.87, no.12, pp.491-509, 1992-12-05 (Released:2008-03-18)

参考文献数

37

被引用文献数

2 8

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合成された純粋な灰長石,それぞれMgO, SiO2に富んだ灰長石を, EPMAと四軸自動X線回折装置を用いて化学組成と格子定数の測定を行い,三宅島産灰長石との比較を行った。複合イオン置換に基づく検討から,天然及び合成の灰長石は, MgをCaMgSi3O8, 過剰のSiは ?? Si4O8端成分として,固溶する可能性が指摘された。さらにMgに対するこの端成分を確認するため, EPMAによるMgの化学シフトを解析した。その結果,合成灰長石に固溶されるMgは,オケルマナイト(Ca2MgSi2O7) 中のMgと同じ四配位席を占有することが示唆された。また, X線単結晶回折法からは, Mgの固溶量が増加するに従って,単位格子の体積が増加する傾向が明らかになった。以上のことから灰長石におけるMgの固溶は,雲母,角閃石,輝石に認められる通常のTschermak置換, Mg+Si ?? ;2Al, とは異なり,四配位席だけでのTschermak置換が,メリライトと同様に灰長石においても成立することを明示している。