著者
舟山 裕士 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.58, no.4, pp.121-135, 1967-10-05 (Released:2008-08-07)
参考文献数
12

The mineral deposits of the Oppu mine, Aomori Prefecture, consist of epithermal fissure-filling chalcopyrite-sphalerite-galena veins in the Neogene sediments. On the basis of lithology and characteristics of sedimentation, stratigraphy of the Oppu mining districts is divided into the following formations: Quaternary Terrace deposits and Talus deposits Oppudake formation Tertiary Miocene Oppu formation Maenosawa formation Koyunosawa formation Yunosawa formation Pre-Tertiary Basement complex The country rocks of the mineral deposits are Oppu formation (andesitic-dacitic lapilli tuff, coarse tuff and siltstone) and Oppudake formation (salic pumiceous tuff). The geological structures are characterized by large domes which are sometimes accompanied with faults and foldings. Faults are common in the area studied and can be classified into the following four major systems-NE-SW system, WNW-ESE system, ENE-WSW system and N-S system. The distribution of mineral deposits and ore shoots have close relations with the some geological structures. For instance, main mineral deposits are located usually in the combination zone of normal and low dipping reverse faults in this mining area. Especially, the veins are controlled by the sedimentary structures and thrust faults (Figure 5). These structural conditions which control the ore shoots have been stressed in this paper.
著者
田窪 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.75, no.9, pp.300-312, 1980-09-05 (Released:2008-08-07)
参考文献数
30
被引用文献数
1 1

Experiments on the crystal growth of materials belonging to the A12O3-TiO2 system and on the high-temperature behaviour of natural star-sapphire were made with special reference to the genesis of regular arrangement of the ruitle needle crystals in and on corundum crystals. The crystals were grown by using direct fusion, flux-fusion and hydrothermal methods under the various conditions of temperature, chemical concentration, cooling mode, temperature gradient and oxygen partial pressure. The following results were obtained: (1) When a thin layer of melt made from TiO2 powder or from mixture of Al2O3 and TiO2 powder was slowly cooled on (0001) face of corundum substrate, the regular arrangement of acicular rutile crystals was easily formed on the substrate. (2) The βAl2TiO5 crystals grown from the melt on the substrate did not show the regular arrangement. (3) When crystals of corundum and rutile were synchronously grown by the monotonous slow-cooling of flux-melt in air, no regular intergrowth appeared in both as-grown and aged corundum crystals. (4) When the intermitent flucutation of temperature was introduced during the slow-cooling in the above method, the conspicuous zonal structure composed of various imperfections appeared in the as-grown corundum crystals. After aging in air, the regular arrangement of rutile appeared on the (0001) faces and along the imperfection zones of corundum crystals. (5) When rutile was crystallized synchronously with corundum or epitaxially on the (0001) face of corundum from flux-melt in oxygen gas flow or from hydrothermal solution, no regular intergrowth was formed. (6) In the presence of flux-melt, the regular arrangement of rutile on the corundum substrate was promoted in air or in reducing atmosphere. (7) Epitaxial growth of corundum on a rutile single crystal did not occur in any of the growth methods mentioned above. (8) When natural star-sapphires were heated above 1200°C, the regular arrangement of rutile needles fell into disorder from surface to inside and finally disappeared with leaving small gas-bubbles. Ti-atoms tended to migrate predominantly towards the surface and into the small cracks where rutile was recrystallized. Based on these results and those reported by other authors, critical examinations were made as to such problems as solubility of Ti into corundum, stability of βAl2TiO3, removal of Ti from corundum technology for synthesis, mechanical behaviour, epitaxis and natural occurrence. As a result of examinations, it seems that the “precipitation from solidsolution” theory, which is generally accepted as to the genesis of regular intergrowth in star-sapphire, is less plausible. Following two theories were developed on the genesis ofstar-sapphire. (1) Secondary and epitaxial crystallization of rutile along open spaces and imperfection-zones such as shear planes, tension cracks, zonal structure and inclusions, most of which are parallel to (0001) face. TiO2-component is supplied not only from the external sources, but also from the internal sources such as the imperfection-zones with higher Ti-concentration. (2) Synchronous and parallel growth of corundum and dendritic rutile crystals, being followed by survival of the twig crystals which preserve proper orientation for epitaxis.
著者
島 誠 永田 武 岡田 昭彦
出版者
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.63, no.6, pp.239-247, 1970

Fine materials (1008489) contains many round shape particles which are almost similar shape and size of cosmic dust. By the chemical composition, they are classified into three groups, 1) Fe-Ni group, 2) Fe, group, and 3) silicate group. The glassy particles composed mainly of silica are thought to be a kind of microtektite which are found on the earth. It is suggested that a part of spherules are extraterrestrial matter.
著者
谷口 広充
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.4, pp.128-138, 1972-04-05 (Released:2008-08-07)
参考文献数
22
被引用文献数
2 3

Towada volcano, which is located in the northeastern part of Honshu, is a typical double caldera of Krakatau type, about 10km in diameter and 500m deep. It is formed on the basement composed of the Tertiary rocks and the Pleistocene volcanic rocks. The volcanic activity of Towada volcano can be divided into two stages by the formation of calderas. At the first stage, the activity is represented by mafic to intermediate andesite. Then, this activity was followed by the eruption of the tremendous amounts of dacitic ash falls and pumice flows. Following this the outer caldera was formed by the collapse of the upper part of the stratovolcanic cone. At the second stage, the activity, which is much smaller than the first cone, is also represented by mafic to intermediate andesite. After this activity much andesitic pumice fall erupted in the Holocene age, resulting in a smaller caldera, called “Nakanoumi”. The rocks of each stage are divided into two rock series, namely pigeonitic rock series and hypersthenic rock series. The earlier eruption is pigeonitic series and the later is hypersthenic. In the first stage activity, the change from pigeonitic series to hypersthenic series is continuous by petrographicaly. A magma of hypersthenic series would be produced by a magma of pigeonitic series by fractional crystallization under higher oxygen partial pressure and lower temperature conditions.
著者
塩沢 孝之
出版者
日本鉱物科学会
雑誌
岩石鉱物鉱床学会誌
巻号頁・発行日
vol.63, no.2, pp.75-84, 1970
被引用文献数
3

筆者は石母狩湾堆積物中の粘土鉱物組成を調べ,その分布を規刷している主な要因が分凝作用であろうと推論した(塩沢,投稿中)。その推論を確めるべく,湾の主要構成粘土鉱物のモンモリロナイト・クローライト・イライト(代りにセリサイト)からなる分散系で分凝作用に関するある種の実験を行なった。<br> それによると,モンモリロナイトは懸濁液攪拌放置後の時間経過に伴って,懸濁液中で相対的に濃集し,クローライト(セリサイトもほぼ同じ)は逆に減少することが明かになった。この分凝作用は一般に塩分濃度と分散系中の粘土鉱物濃度の増加にともなって顕著になる。この結果は, Whitehouseら(1960) の単一鉱物の分散系で行なった実験結果からほぼ説明される。今回の実験結果は,石狩湾に関する筆者の推論が正しいであろうことを裏づけた。
著者
鈴木 醇
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.27, no.5, pp.229-239, 1942-05-01 (Released:2008-03-18)
参考文献数
6
被引用文献数
2
著者
大泉 製次
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.58, no.3, pp.103-115, 1967-09-05 (Released:2008-08-07)
参考文献数
15

Takagami Mine is situated 22 kilometers south of Yamagata City. The mine area and the neighboring region is underlain by Miocene sediments, with granodiorite exposed in the southern part serving as the basement. The ore-deposits are of fissure-filling type, with some network and impregnation portions. The deposits occurring in fissure zones and faults are controlled by the geological structure of the basement and the sediments. Oreshoots occur as chimneys crossing fractures and faults. Ore minerals are mainly pyrite and chalcopyrite with accompanying sphalerite, gold and argentite. In some portions the grade of gold is high. Gangue minerals are mainly quartz and clay minerals. This report is part of the relation between geological structures and ore deposits of the Yamagata Basin.
著者
鈴木 滋 西戸 裕嗣 大塚 良平
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.8, pp.238-247, 1976
被引用文献数
1

東京都小笠原父島北東海岸の初寝浦付近には,無人岩の枕状溶岩が広く分布している。筆者らの一人(西戸)はその空隙をうめて,キフッ石,モウフッ石,カイジュウジフッ石などのフヅ石および緑色粘土を伴なって産する淡褐色の粘土を見い出した。その後の室内研究により,この粘土は加水タルクを主とし,極く少量中の不透明鉱物を伴なうことが明らかにされた。その粘土の化学分析の結果から, 22の陽電荷をもとにして求めた構造式は以下の通りである。<br> (Mg<sub>2.87</sub>Mn<sub>0.02</sub><sup>2+</sup>Fe<sub>0.09</sub><sup>3+</sup>)(Si<sub>3.95</sub>Al<sub>0.01</sub>)0<sub>10</sub>(OH)<sub>2</sub>・Ca<sub>0.03</sub>・Na<sub>0.05</sub>・K<sub>0.01</sub>・<sub>n</sub>H<sub>2</sub>O.<br> この論文では,このほかにその陽イオン交換能および交換性イオン, X線回折データ,熱分析データ,赤外吸収スペクトル,電子顕微鏡像が示されている。
著者
草地 功 逸見 千代子 逸見 吉之助
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.79, no.7, pp.267-275, 1984-07-05 (Released:2008-08-07)
参考文献数
15
被引用文献数
10 20

岡山県川上郡備中町布賀にはゲーレン石・スパー石スカルンが発達している。そのうち道路際露頭と称されている露頭のスパー石スカルン中に大江石を含む輻 1-3cm の細脈を見出した。共生鉱物としては大江石の他に,バルトフォンテイン石,スコート石,ゾノトラ石,方解石がある。大江石とスコート石はスパー石スカルン形成後の割目充填鉱物として初生的に生成され,脈中では中心部のスコート石帯の両側に,各々が 1-3mm の幅で交互に2条ずつ配列する対称的な帯状構造を示している。バルトフォンテイン石,ゾノトラ石は大江石,スコート石生成後の作用により,スコート石から二次的に生成されたものである。 この論文は大江石,パルトフォンテイン石,スコート石についての化学組成, X 線粉末回折値,光学的性質および物理的性質を求めるとともに,大江石を含む脈の構成鉱物の生成過程を考察した。
著者
関 陽太郎 平野 富雄 渡辺 邦夫
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.82, no.7, pp.269-279, 1987-07-05 (Released:2008-08-07)
参考文献数
9
被引用文献数
4 6

Rock-cliff Budda sculptures of Odaka Town, Fukushima Prefecture, Japan were carved about one thousand years ago on the Neogene dacitic tuffaceous sedimentary rocks. These sculptures have been badly decayed by (1) the formation of scabs composed chiefly of gypsum, epsomite and thenardite with subordinate amounts of kogarkoite, langbeinite, zoherite, hydroglauberite, starkeyite, jurbanite, loeweite, hexahydrite, alunogen, mirabilite, glauberite, syngenite, hemihydrite and sylvite at the surface of the sculptures by the evaporation of groundwater percolated through the voids and joints in the Neogene volcanogenic sedimentary rocks and (2) the exfoliation of the these scabs and near-surface part of Neogene sedimentary rocks, particularly due to the heaving during the freezing-thawing cycle of seeped groundwater in winter season.
著者
齋藤 一夫
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.76, no.10, pp.315-323, 1981-10-05 (Released:2008-08-07)
参考文献数
8

It has been long understood that some elements tend to be found as sulfides in nature, whilst others as oxides. The importance has been recognized by both chemists and geologists, but chemists were unable to interpret the reason for such difference in occurrence. The abundance of the elements in the space is determined by the characteristics of the nuclides of the elements; i. e. by the rate at which the particular nuclide is synthesized from lighter nuclides. On the other hand, the chemical form of the elements in nature is largely dependent on the electronic structure of the atoms. Recent studies of the stability of various coordination compounds in aqueous solution give useful information for interpreting the affinities of elements towards oxide and sulfide.
著者
青木 義和
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.Special3, pp.123-128, 1982 (Released:2012-08-03)
参考文献数
10

Large numbers of [100], [110] and [111] penetration twins are formed during growth of KC1 crystals from solution. All of them are interpenetrating octahedrons with rotation of some angles about [100], [110] and [111] common axis of two individuals, respectively. Twin formation appeared to be favored by Pb2+ and relatively high supersaturation. The maximum yield of twins is obtained at the region of 0.4-0.6 g Pb2+/l H2Oand σ=0.1-0.4. The formation is discussed in terms of rotation twinning, on the basis of the concept of coincidence-site lattices. Good agreement is obtained between the angles of some crystallographic directions observed in the twins and those expected from this concept.
著者
長谷川 修三
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.39, no.5, pp.194-203, 1955-10-01 (Released:2008-03-18)
参考文献数
20

興田産コランダムは珪線石ホルンフェルス中に正長石を伴い,径1cm以下の変斑晶として多数存在する。結晶形はc(0001), a(1120)及びr(1011)より成る六角板状で薄青色を呈する。その比重,屈折率はG4 ?? 180=3.964,ω=1.768,ε=1.761で化学組成は略々Al2O3に相当する。 スカルン帯に豊富に存在する黄褐色の柘榴石の比重,屈折率は夫々G4 ?? =3.831,nD=1.8888であり,化学分析の結果から求めた端成分はAnd 91.9, Gr 4.1, Alm 1.7, Sp 2.3mol%である。尚,本コランダムの成因にっいての一考察を述べた。
著者
兼平 慶一郎 坂野 昇平 由井 俊三
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.70, no.11, pp.388-394, 1975-11-05 (Released:2008-08-07)
参考文献数
7
被引用文献数
3 8

南房総嶺岡地域の蛇紋岩化されたカンラン岩中にアワル鉱,ヒーズルウッド鉱および自然銅が見出された。これらの鉱物は岩石中の蛇紋岩化された部分にのみ見出され,蛇紋岩化作用のときに形成されたものである。分析されたアワル鉱の組成はNi2.26Feである。また,ヒーズルウッド鉱と共存する自然銅は数パーセントのニッケルを含んでいる。アワル鉱の存在は蛇紋岩化作用が還元的な環境のもとで行われたことを示している。
著者
大泉 製次
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.58, no.1, pp.31-38, 1967-07-05 (Released:2008-08-07)
参考文献数
10

Shirataka Mine is situated between On Mountains and Dewa Hills in the southern part of Central Yamagata Prefecture. The Mine Area is underlain by Miocene strata, i.e.: 1) Yoshinogawa formation, 2) Motozawagawa formation, 3) Shimoyama formation, 4) Ose tuffaceous sandstone member and 5) Sugiyama formation. Shimoyama formation is interfingered with Yoshinogawa and Motozawagawa formations. Yoshinogawa formation is correlated to the Daijima and Nishikurosawa formations, while Motozawagawa formation is correlated to the Onnagawa formation. In the western part of the region, hornblende-biotite granodiorite basement rocks are exposed. In the northeastern part, Quaternary volcanics in the Shirataka Mountain, andesite flows and pyroclastics are found. The ore deposit is of the network type, and it is strongly controlled by geologic structures. Fractured zone generally trend N30E. Ores shoots follow the same trend, but, they dip more steeply. At the upper reaches of the Kaaehorizawa River, kaolinization and pyritization with accompanying mineralization is pronounced. This report presents the studies made on the relationship between ore deposition and structural control of volcanism inherent to the Zao-Shirataka volcanic structural line.
著者
奥村 滋
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.6, pp.191-202, 1982-06-05 (Released:2008-08-07)
参考文献数
24
被引用文献数
1 1

Nabari gabbroic body, which belongs to Ryoke Complex, occurs in the mesa-like hill in the southern part of Iga basin, Mie Prefecture, Southwest Japan, and a thick weathering crust occurs at the top level of the hill. Based on geological and mineralogical studies on neoformation minerals in saprolites and modes of occurrence of core stones with or without “shells”, weathering crust can be divided into three zones, I, IIa and IIb, as follows; Zone I: kaolin+goethite in saprolite, presence of a core stone coated by shell with gibbsite, Zone IIa: smectite+kaolin±goethite in saprolite, presence of a core stone coated by shell free from smectite, Zone IIb: smectite+kaolin±goethite in saprolite, presence of a core stone without shell. Zoning of weathering crust is nearly horizontal and water table lies near the bottom of the zone IIa. Therefore, authigenic occurrence of neoformation minerals in each weathering zone is considered to reflect the hydrolytic decomposition of primary aluminosilicate minerals by percolating meteoric water and stagnant ground water in weathering crust. The relationships among authigenic formation of minerals in weathering crust, parent rock composition and environmental variables, such as climatic and time factors, are briefly discussed in this paper.
著者
渡邊 萬次郎 黄 春江
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.28, no.4, pp.184-204, 1942
被引用文献数
1

黄金坪礦床は岩手縣江刺郡伊手村の東部に属する北上山地の西佐縁部に在り,東北本線水澤驛より自動車約1時闇の行程にあり。<br> 地質は主として石灰岩及び基性火山岩乃至その凝灰岩の接觸變質物と認められる緑色變憂成岩と,これを貫ぬく糲岩及び石英斑岩乃至花崗岩から成る。<br> 斑糲岩の輝石は大部分ウラル石化し,且つ一部分黒雲母化し,石英斑岩の影響を受けたものと認められろ。<br> 礦床の一部は普通の含金石英脈で,斑糲岩,石英斑岩等を貫ぬくが,一部は斑糲岩の内部がぼゞ直立の圓〓状に角礫化し,その間隙を網状に貫ぬいた石英灰重石脈から成り,タングステン礦として開發せられる。<br> 灰重石は最初の晶出物であり,石英には微量の磁硫鐵礦,閃亜鉛鑛,黄銅礦を伴なつて金を含む。<br> 母岩の一部は黒雲母化,繊維状角閃石化,縁泥石化作用を受け,かゝる部分は概ね多量の灰重石をそのうちに生じた。<br> 母岩は多数の節理に富み,礦床は地下から4昇した高温高壓の熱水溶液が,その通路に當る母岩の節理に侵入し,これを押し擴げてその間隙に石英次重石等を生じた結果と認められる。<br> 本磯床の成生後,熱水溶液の張力によるstressの減少に伴なひ,礦床の一部は陥没し,その結果としてその邊縁ぬく断層を生じ,これまたその後の熱水溶液の通路となり,含金石英脈を生じたものと認められる。
著者
西川 一雄 西堀 剛 小早川 隆 但馬 達雄 上嶋 正人 三村 弘二 片田 正人
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.2, pp.51-64, 1983-02-05 (Released:2008-08-07)
参考文献数
24
被引用文献数
3 4

The late Cretaceous Koto Rhyolite is divided into two groups according to the succession. Each group forms an igneous cycle. The older group consists of the Kaiwara Welded Tuff and the Hatasho Quartz Porphyry, and their relationship is transitional in the field showing their co-magmatic origin. The Kaiwara Welded Tuff erupted apparently first as vesiculated magma from the top of the magma_??_reservoir followed by the intrusive phase of the Hatasho Quartz Porphyry. There are enrichment of phenocrysts such as quartz and alkali feldspar in the Kaiwara Welded Tuff, whereas plagioclase phenocrysts are more commo in the Hatasho Quartz Porphyry. The K/Rb ratios of the whole rocks are larger in the Hatasho Quartz Porphyry than in the Kaiwara Welded Tuff. The younger group consisting of the Yatsuoyama Pyroclastic Rock and the Inugami Granite Porphyry is also considered to be of co-magmatic origin although obvious intimate relationship of the two units could not be observed in the field. The differences between them in the composition of phenocryst minerals and K/Rb ratio of the whole rocks are similar to and somewhat larger than those between the Kaiwara Welded Tuff and the Hatasho Quartz Porphyry. The Inugami Granite Porphyry of the last igneous activity intruded along the ring faults whose center subsided stepwise and resulted in a double ring dike about 30km across. Thus the Koto Cauldron was composed. Natural remanent magnetism through the Koto Rhyolite suggests a clock-wise movement of the area during its igneous activity.