著者
南部 松夫 谷田 勝俊 北村 強
出版者
Japan Association of Mineralogical Sciences
雑誌
岩石鉱物鉱床学会誌 (ISSN:00214825)
巻号頁・発行日
vol.62, no.6, pp.311-328, 1969-12-05 (Released:2008-08-07)
参考文献数
31
被引用文献数
6 11

New mineral kôzulite belongs to the alkali amphibole group in which manganese (II) is the predominant cation of the Y-position. The mineral occurs as banded aggregate of short prismatic crystala with the faces of b, m and r up to 3.5×2.0×1.5mm in size, in the bedded magnanese deposit of Tanohata Mine, Iwate Prefecture, Japan, in the highly metamorphosed Jurassic chert-hornfels by the intrusion of granodiorite. Associated minerals are braunite, rhodonite, manganiferou alkali pyroxene, manganiferou alkali amphibole and quartz. Color reddish black to black, streak light purplish brown, luter vitreous, H. 5, G. measured 3.30, calculated 3.36. Cleavage (110) perfect. Optically biaxial negative, ns α=1.685, β=1.717(mean), γ=1.720, 2Vα=34-36°, cΛX=25°. Strongly pleochroic with X yellow-brown, Y reddish brown, Z dark brown, absorption Z〉Y〉X, dispersion very weak, probably r〉v. Chemical analysis gave SiO2 51.38, TiO2 none, Al2O3 1.69, Fe2O3 2.85, FeO none, MnO 27.96, ZnO 0.03, MgO 2.71, CaO 1.12, BaO none, Na2O 8.41, K2O 1.36, H2O (-) 0.06, F 0.08, sum 99.75-O (=F2) 0.03=99.72%, corresponding to (Na2.54 K0.27 Ca0.19)3.00 [(Mn3.69 Mg0.63)4.32 (Fe+30.33Al0.31)0.64]4.96Si8.00O21.78[(OH)2.18F0.04]2.22, as O+OH+F=24. The x-ray powder data showed the mineral to be monoclinic with a0=9.91, b0=18.13, c0=5.28Å, β=104.5° and precession photographs of the same specimens by N. Morimoto, Osaka University, showed it to be monoclinic, space group C2/m, a=9.91±0.02, b=18.11±0.04, c=5.30±0.02Å, β=104.6°±0.1°, Z=2. The strongest x-ray lines are 8.51 (100) (110), (4.52) (10) (040), 3.40 (10) (131), 3.29 (17) (240), 3.15 (67) (310), 2.96 (6) (221), 2.827 (31) (330), 2.748 (8) (331), 2.722 (10) (151), 2.602 (6) (061), 2.545 (6) (202), 2.349 (7) (351), 2.174 (9) (261), 1.908 (7) (510), 1.447 (7) (661). The high-temperature x-ray study and DTA indicate that the mineral breaks down to braunit plus glas at about 950°C. The name is for late Dr. Shukusuke Kôzu (1880-1955), formerly Professor in Tohoku University, Japan who made many contributions to the study of rock forming minerals. Type material is preserved at Tohoku University. The mineral and name were approved before publication by the Commission on New Minerals and Mineral Names, IMA.
著者
平島 崇男
出版者
Japan Association of Mineralogical Sciences
雑誌
岩石鉱物鉱床学会誌 (ISSN:00214825)
巻号頁・発行日
vol.78, no.3, pp.77-83, 1983-03-05 (Released:2008-08-07)
参考文献数
13
被引用文献数
11 15

関東山地において,ひすい輝石+石英組合せを持つ岩石を新たに発見した。この岩石は第三紀の栃谷層と断層関係にある超塩基性岩とともに露出している。この岩石は,ひすい輝石+石英組合せが安定な変成作用(高圧条件)と,アルバイト+エジル輝石が安定な変成作用(中圧条件)の2回の温度圧力条件を記録している。
著者
秋月 瑞彦
出版者
Japan Association of Mineralogical Sciences
雑誌
岩石鉱物鉱床学会誌 (ISSN:00214825)
巻号頁・発行日
vol.71, no.Special1, pp.105-118, 1976-07-15 (Released:2012-08-03)
参考文献数
45
著者
島 誠
出版者
Japan Association of Mineralogical Sciences
雑誌
岩石鉱物鉱床学会誌 (ISSN:00214825)
巻号頁・発行日
vol.54, no.6, pp.216-221, 1965-12-05 (Released:2008-08-07)
参考文献数
4

Within recent years, the meteorite has become an interesting material on the geochemistry and the cosmochemistry. The Komagome iron meteorite had been one of the doubtfull meteorite in Japan. According to literatures, it fell 18th April 1926 in Tokyo and was 238g (weight). The present paper describes the following results. Ni and Co contents of this iron meteorite were about 8.0% and about 0.5% respectively. On the distribution pattern of the schreibersite, it was shown by the electron probe X-ray microanalyzer. The schreibersite was always occupied the center of the troilite phase.
著者
小林 暉子
出版者
Japan Association of Mineralogical Sciences
雑誌
岩石鉱物鉱床学会誌 (ISSN:00214825)
巻号頁・発行日
vol.81, no.10, pp.399-405, 1986-10-05 (Released:2008-08-07)
参考文献数
4
被引用文献数
3 3

Existence of uvarovite has not been reported so far in Japan. Specimens labeled uvarovite crystals from 19 localities in Sakurai Collection were analysed by an electronprobe microanalyser, confirming some uvarovite crystals. Uvarovite and Cr-bearing andradite occur in a fine vein in aggregate of chromite or magnesiochromite. In serpentine with diopside or talc occur uvarovite, Cr-bearing andradite and Cr-bearing grossular.
著者
平島 崇男
出版者
Japan Association of Mineralogical Sciences
雑誌
岩石鉱物鉱床学会誌 (ISSN:00214825)
巻号頁・発行日
vol.78, no.3, pp.77-83, 1983
被引用文献数
1 15

関東山地において,ひすい輝石+石英組合せを持つ岩石を新たに発見した。この岩石は第三紀の栃谷層と断層関係にある超塩基性岩とともに露出している。この岩石は,ひすい輝石+石英組合せが安定な変成作用(高圧条件)と,アルバイト+エジル輝石が安定な変成作用(中圧条件)の2回の温度圧力条件を記録している。
著者
渡辺 一徳 勝井 義雄
出版者
Japan Association of Mineralogical Sciences
雑誌
岩石鉱物鉱床学会誌 (ISSN:00214825)
巻号頁・発行日
vol.71, no.2, pp.44-49, 1976-02-05 (Released:2008-08-07)
参考文献数
16
被引用文献数
28 30

阿蘇カルデラ内北部の本塚・北塚・灰塚はいずれも石英安山岩の溶岩からなる古い中央火口丘で,それらの下底部には海抜約510mのレベルまで水冷により破砕された溶岩が発達している。故にこの水中溶岩が噴出した時期にはカルデラはこのレベルまで湖であったと推定される。この水中溶岩は大小の岩塊と同質の細片からなり,その中には枕状溶岩に類似した柱状節理をもつ岩塊が含まれている。この種の岩塊は多くの点で通常の枕状溶岩とは異なっているので,偽枕状溶岩と呼ぶことにする。その産状の詳細な観察によれば,偽枕状溶岩は,水中を前進中の粘性の高い溶岩に湾曲した割れ目がはいり,これに沿って侵入した水で急冷され,分離したものである。このため偽枕状溶岩は表面に垂直な柱状節理を生じているが,通常の枕状溶岩とちがって外形はもとの流理構造を明瞭に切っている。
著者
小島 晶二 苣木 浅彦
出版者
Japan Association of Mineralogical Sciences
雑誌
岩石鉱物鉱床学会誌 (ISSN:00214825)
巻号頁・発行日
vol.78, no.12, pp.491-496, 1983-12-05 (Released:2008-08-07)
参考文献数
13

From the Senzai vein of the Oe mine situated in southwestern Hokkaido, some kinds of rhodochrosite stalagmites are sometimes found out at the bottom of druse within the vein. The stalagmites show the shape of column, 2 to 30mm in diameter and 1 to 12cm in length. They consist of irregular fan-shaped crystals superficially and show the solution growth textures such as concentric bandings. These stalagmites have the chemical compositions of 53 to 89 mole % MnCO3, 2 to 20 mole % CaCO3. 7 to 26 mole % FeCO3 and 1 to 9 mole % MgCO3, which are mostly within the compositional region of drusy rhodochrosite of the vein. Chemical compositions of the rhodochrosite stalagmites change markedly with the concentric bands as shown in Fig. 7, which shows considerable increase of MnCO3 content from core to rim. This feature is considered as being due to chemical changes of the ore solution or ground water producing the rhodochrosite stalagmite.
著者
天白 俊馬
出版者
Japan Association of Mineralogical Sciences
雑誌
岩石鉱物鉱床学会誌 (ISSN:00214825)
巻号頁・発行日
vol.77, no.4, pp.125-136, 1982-04-05 (Released:2008-08-07)
参考文献数
40
被引用文献数
1

The Cretaceous Hiroshima granite of the Hiroshima-Iwakuni area is divided petrographically into two types, e. g. biotite granite and hornblende-bearing biotite granite. The dark inclusions in the latter are characterized by containing hornblende commonly, while those associated with the former granite are hornblende-free, tiny in size, and also small in amount. Plotting the chemical compositions on the normative An-Ab-Or diagram, these two types of granite are quite different in trend, although there is no distinct difference on the Thornton-Tuttle's variation diagrams. This cannot be explained by the difference of fractionation and also by the change in partial PH2O of magma under cooling condition. Irregular shape and uneven distribution of hornblende in hornblende-bearing biotite granite indicate that this hornblende was not the crystallization product of granite magma, but was accidental xenocryst transported into the magma. This fact and the difference of trend in the An-Ab-Or diagram suggest the contamination of granite magma by the hornblende-bearing dark inclusions.
著者
藤縄 明彦
出版者
Japan Association of Mineralogical Sciences
雑誌
岩石鉱物鉱床学会誌 (ISSN:00214825)
巻号頁・発行日
vol.77, no.12, pp.419-437, 1982
被引用文献数
1 2

In order to understand the generation and differentiation processes of the island arc tholeiite magma, it is essential to reveal the crystallization sequence of the minerals in the shallow magma chamber.<br> For that purpose, a microprobe study has been undertaken on three Funagata pigeonite basalts which are the most primitive basalts among the island arc tholeiitic series in the Nasu zone, NE Japan. Firstly, the crystallization sequence recognized in each sample has been clarified based on chemical compositions and textural relations. Secondly, information on the near equilibrium crystallization in the shallow magma chamber has been extracted and connected.<br> The crystallization sequence obtained through the study is as follows.<br> Stage A: Plagioclase (An<sub>90</sub>+), olivine (Fo<sub>78</sub>), bronzite (Wo<sub>4.5</sub> En<sub>76</sub>Fs<sub>19.5</sub>) and pigeonite (Wo<sub>9.5</sub>En<sub>71</sub>Fs<sub>19.5</sub>) coexist with liquid. At this stage, olivine has already been in reaction relation with liquid to form bronzite and/or pigeonite. Bronzite is also in reaction relation with liquid to form pigeonite.<br> Stage B: Mafic minerals gradually enrich in Fe<sup>2+</sup>. When the Mg/(Mg+Fe) ratio of the pigeonite reaches 0.23, augite begins to crystallize. Penecontemporaneously with the start of the augite crystallization, olivine (Fo<sub>75</sub>) is fractionated from the liquid. An mole % of the plagioclase is nearly constant.<br> Stage C: The three pyroxenes further enrich in Fe<sup>2+</sup>. Three pyroxene coexistence continues until the Mg/(Mg+Fe) of the pigeonite reaches 0.26. Chemical composition of the plagioclase is nearly constant (An<sub>90</sub>).<br> Experimental data indicate that the crystallization sequence obtained here must reflect the notable change of the pyroxene phase relation in the early stage differentiation of the Funagata tholeiitic basalt magma. This type of change in pyroxene phase relation is interpreted as being due to the successive decrease of the liquidus and solidus temperatures of pyroxenes, accompanied with the proceeding of the differentiation.
著者
関 陽太郎 奥村 公男
出版者
Japan Association of Mineralogical Sciences
雑誌
岩石鉱物鉱床学会誌 (ISSN:00214825)
巻号頁・発行日
vol.60, no.1, pp.27-33, 1968-07-05 (Released:2008-08-07)
参考文献数
8
被引用文献数
4 4

宮城県鬼首地熱地帯に地熱開発のためにほられたボーリングのコアから湯ケ原沸石が発見された。この地熱地帯は,ボーリングコアでの観察によると,深部から浅部にむかって,ワイラカイト,ワイラカイト・ローモンタイト,ローモンタイト,モルデナイト,および無沸石の5つの帯にわけられる。湯ケ原沸石はローモンタイト帯に存在する。湯ケ原沸石のX線データを記し,あわせて湯ケ原沸石の化学成分についてふれた。
著者
三浦 清
出版者
Japan Association of Mineralogical Sciences
雑誌
岩石鉱物鉱床学会誌 (ISSN:00214825)
巻号頁・発行日
vol.56, no.6, pp.256-283, 1966-12-05 (Released:2008-08-07)
被引用文献数
1 2 1

The geology, petrographic characters of the granites, and the types of collapses of the rocks caused by heavy rain fall in the Kamo District, Shimane Prefecture, are described to clarify the relation between rock types and collapsing phenomena in the granite mountain area. The granitic rocks comprise granodiorite and biotite granite, and both are weathered remarkably in most parts. From the genetic point of view, the collapses are classified into six types. 1) Collapse, closely related to the joint structure of the rocks; they occur characteristically at the foot of slopes in the region of weathered granodiorite. 2) Collapse of the weathered zone (uppermost layer covered with vegetation) of slopes, caused by difference of physical properties to the ground water between the weathered zone and the basement rocks. 3) Collapse with characters of (1) and (2). 4) Collapse closely related with dikes in granite. 5) Collapse accompanying landslide in fault breccia zones. 6) Collapse or resliding of the talus deposit, made by an older land slide of the adjoining rock masses. The majority of the collapses in this district belong to types (1), (2) and (3). Types (1) and (2) predominate in granodiorite and (3) in biotite granite.
著者
蟹沢 聰史
出版者
Japan Association of Mineralogical Sciences
雑誌
岩石鉱物鉱床学会誌 (ISSN:00214825)
巻号頁・発行日
vol.48, no.2, pp.67-75, 1962-08-05 (Released:2008-08-07)
参考文献数
5

The Ryoke metamorphic rocks of the Takato district are composed mainly of pelitic and psammitic rocks, with subordinate amounts of basic volcanic rocks and limestone. The grade of metamorphism of the district increases progressively from the northwest to the southeast. Petrofabric analysis has been carried out for biotite, muscovite and quartz in the pelitic schistose hornfelses and gneisses of the district. Biotite and muscovite fabrics are generally determined by the bedding schistosity, and quartz fabrics of the schistose hornfelses show weak symmetry and ac-girdle, while those of the gneisses do not show any symmetrical pattern. When compared with those of the Yanai district belonging to the Ryoke metamorphic belt in southwestern Japan, the fabric diagram mentioned above are less symmetrical. This fact may suggest that the movement during the Ryoke metamorphism was different between the Takato and the Yanai districts.
著者
中川 善兵衛 小坂 丈予 浦部 和順 山田 久夫
出版者
Japan Association of Mineralogical Sciences
雑誌
岩石鉱物鉱床学会誌 (ISSN:00214825)
巻号頁・発行日
vol.67, no.9, pp.283-290, 1972-09-05 (Released:2008-08-07)
参考文献数
12
被引用文献数
1 2

The weathering process of quartz-diorite mass in Senmaya district, Iwate Prefecture, was studied from chemical and mineralogical angles. Especially the relationship between the compositional changes of the weathered rocks and their main constituent minerals was detailedly discussed. The non-altered quartz-diorite is chiefly composed of quartz, plagioclase, hornblende and biotite, together with few apatite and magnetite. As weathering proceeds, most of the primary minerals, plaigoclase, hornblende and biotite, are gradually eliminated and secondary minerals such as vermiculite, kaolin etc. appear in stead. The change in chemical composition of the weathered rocks is almost controlled by the solubility of each chemical component under netural conditions. Among the primary minerals, biotite is most sensitive for weathering, the sequence of the alteration being as follows:biotite-hydrobiotite-vermiculite-kaolin mineral In the earlier stage of the weathering, the alteration process of biotite was mostly affected by its original crystallographic structure, so that the change in chemical composition of that mineral differs markedly from that of the host rock. But it is also controlled by the solubility of each chemical component, thus the compositional change becomes to be similar to that of the host rock in the later stage.
著者
木下 龜城
出版者
一般社団法人 日本鉱物科学会
雑誌
岩石鉱物鉱床学会誌 (ISSN:00214825)
巻号頁・発行日
vol.25, no.1, pp.29-36, 1941-01-01 (Released:2008-03-18)
参考文献数
5
著者
竹内 常彦 舟山 裕士 山岡 一雄 阿部 宏
出版者
Japan Association of Mineralogical Sciences
雑誌
岩石鉱物鉱床学会誌 (ISSN:00214825)
巻号頁・発行日
vol.54, no.4, pp.113-126, 1965-10-05 (Released:2008-08-07)
参考文献数
29
被引用文献数
1 1

The Obanazawa mine is situated about 9.5km north-east of Obanazawa City, Yamagata Prefecture, northeastern Japan. The ore deposit is made up of copper-zinc quartz veins developed in dacite and dacitictuff of Miocene age. Ore minerals are chalcopyrite, sphalerite, pyrite, tetrahedrite and ferberite. The pyrite has either pentagonal dodecahedral form or colloform textures. This is the first occurrence of ferberite in the green tuff region of the inner zone of northeastern Japan. Hexagonal; platy crystals of pyrite are observed in the vein found in the Komatazawa valley. It seems that they were crystallized as pyrrhotite single crystals and altered to pyrite aggregates after the formation of the vein. Gangue mineral is quartz accompanied by a small amount of barite. Argillization (mainly sericitization) and silicification are distinguished. Ferberite was identified by means of X-ray and chemical analysis; the composition is (Fe0.90 Mn0.10)WO4. Occurrence of ferberite and pyrite after pyrrhotite means that the veins may have formed at high temperature but the properties of other vein minerals suggest that they crystallized at low temperature. They have been explained as a telescoping phenomena of xenothermal type deposits in the greentuff region. The Obanazawa mine is situated at the intersection of N-S and NWSE main structural lines of northeastern Japan ; the basement of this area seems to be uplifted. The mineral assemblages of this ore deposit may be explained by assuming that a subvolcanic magma chamber exists in this area.
著者
加納 博
出版者
Japan Association of Mineralogical Sciences
雑誌
岩石鉱物鉱床学会誌 (ISSN:00214825)
巻号頁・発行日
vol.75, no.Special2, pp.375-383, 1980-08-30 (Released:2012-08-03)
参考文献数
59

The Aubukuma Metamorphic Belt is famous by the petrological work of Miyashiro (1958, etc. ). But his scheme on the metamorphic history has been largely rewritten by the Research Group of the Abukuma Plateau including Y. Kuroda, K. Uruno, K. Nureki, I. Hara, S. Kanisawa, T. Maruyama, H. Umemura and the author who proposed the hypothesis of polymetamorphic basement. The hypothesis has been evidenced, first, by the discoveries of polymetamorphic relics - of kyanite and staurolite from the Gosaisho-Takanuki metamorphic rocks and secondly, by the confirmation of Rb-Sr isochron ages of 400 to 600 m. y. of the Ishikawa, the Miyamoto, and the Samegawa plutonic masses. Since 1963 they have been engaged with research from such standpoint and the up-to-date data has been published in the memoir titled “The Basement of the Japanese Islands”However the idea of the polymetamorphic basement should be desce n ded from the “Diaphthoritic Rocks” prese nted by K. Sugi (1935) and his first finding of staurolite from Shiiohira coal mine. The detailed review will be described in the text.