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九州の鉱床を伴う新第三紀および第四紀火成岩の地球化学
http://hdl.handle.net/10232/12640
http://hdl.handle.net/10232/12640eeec220a-df60-4d6f-a305-91c38e3b0485
| 名前 / ファイル | ライセンス | アクション |
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rikouron61.pdf (781.7 kB)
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Diss_FURUSAWA_Miyuki_2012.pdf (9.8 MB)
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| Item type | 学位論文 / Thesis or Dissertation(1) | |||||
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| 公開日 | 2015-02-18 | |||||
| タイトル | ||||||
| タイトル | 九州の鉱床を伴う新第三紀および第四紀火成岩の地球化学 | |||||
| タイトル言語 | ja | |||||
| タイトル | ||||||
| タイトル | Geochemistry of igneous rocks associated with ore deposits from Neogene to Quaternary periods in Kyushu | |||||
| タイトル言語 | en | |||||
| タイトル | ||||||
| タイトル | キュウシュウ ノ コウショウ オ トモナウ シン ダイサンキ オヨビ ダイヨンキ カセイガン ノ チキュウ カガク | |||||
| タイトル言語 | ja-Kana | |||||
| 著者 |
古澤, 美由紀
× 古澤, 美由紀 |
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| 言語 | ||||||
| 言語 | jpn | |||||
| 資源タイプ | ||||||
| 資源タイプ識別子 | http://purl.org/coar/resource_type/c_db06 | |||||
| 資源タイプ | doctoral thesis | |||||
| アクセス権 | ||||||
| アクセス権 | open access | |||||
| アクセス権URI | http://purl.org/coar/access_right/c_abf2 | |||||
| 要約 | ||||||
| 内容記述タイプ | Other | |||||
| 内容記述 | It is well known that the mineralization in Japan is closely related to magmatism. However, the arguments have remained on the geochemical contribution of magma. In this thesis, the geochemical features of igneous rocks are examined for Neogene granitoids and Pliocene to Holocene volcanics in Kyushu, focusing on the anions. Assuming that hydrothermal fluid emanates from magma, I tried to understand the behavior of anions of magma from plutonic and volcanic rocks. The first chapter is occupied by introduction and summary of the present research. The second chapter is spent on Neogene granitoids in Kyushu. Kyushu is divided into three petrographic zones (Outer zone 1, Outer zone 2, and Inner zone from the Pacific Ocean to the Eurasian Continental side). These zones are identified by accompanied mineralizations; Sn-W, Sn-base metal and base metal, respectively, and also by increasing magnetic susceptibility, increasing S isotopic ratio and increasing fHCl/fHF from the Pacific Ocean to the Eurasian Continental side. The evidences suggest that the magmas in the Outer zone have mellowed in the accretionary prism and those in the Inner zone have been generated in the lower crust, and that the fluid with W fluor-complex was transported from magma in the Outer zone and base metal chloro-complex in the Inner zone. Halogen elements played an important role in ore transportation. On the other hand, sulfur behaved in another way. Oxidized sulfur species discharge from magma in the Inner zone, but in plutonic rocks of the Outer zone, reduced sulfur species remain in magma and precipitate as sulfide. The third chapter is spent discussing the Pliocene to Holocene volcanic rocks in the Hokusatsu gold mining district of Kagoshima Prefecture. In the first section, I discuss the geochemical features of volcanic rocks in the whole of the Hokusatsu gold mining district. It is said that these magma might be generated in the lower crust (Hosono et al., 2008). The geochemistry of Nb, Y, Th and other trace elements suggest that two kinds of volcanism exist in this district; islands arc and within plate types. The zonation of islands arc type suggests that the volcanic front and trench have jumped to the eastern side intermittently, and that many epithermal gold deposits were formed associated with chlorine rich magma along the subduction front. In the second section, the dacitic magma in the Hishikari gold mining area in the Hokusatsu gold district is discussed, based on the geochemistry of the volcanic rock. Gold was transported through two steps. Au chloro-complex and oxidized sulfur species (SO_2) were discharged individually from oxidized dacitic magma. After emanation from magma, Au chloro-complex was decomposed and SO_2 was reduced to H_2S, in the overlying reduced Shimanto Supergroup. The gold separated from chlorine connected with H_2S to form Au bisulfide complex, which would be transported through Shimanto Supergroup. Near the surface, the ore fluid mixed with oxic meteoric water, and Au bisulfide complex was decomposed and precipitated as native gold or electrum which forms the Hishikari epithermal gold ore deposits. The fourth chapter is a general overview, and discusses features of the magma both from plutonic and volcanic rocks, from the aspect of mineralization mechanism; origin, transportation, and precipitation of metal. That is, the magma accompanied even with hypogene or supergene ore deposits are characterized by the large contribution of anions such as halogen elements and sulfur. |
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| 内容記述言語 | en | |||||
| 要約 | ||||||
| 内容記述タイプ | Other | |||||
| 内容記述 | 理工学研究科博士論文 (理学) ; 学位取得日: 平成24年3月15日 | |||||
| 内容記述言語 | ja | |||||
| 作成日 | ||||||
| 日付 | 2012-03-15 | |||||
| 日付タイプ | Issued | |||||
| 出版タイプ | ||||||
| 出版タイプ | VoR | |||||
| 出版タイプResource | http://purl.org/coar/version/c_970fb48d4fbd8a85 | |||||
| NDC | ||||||
| 主題Scheme | NDC | |||||
| 主題 | 450 | |||||
| ファイル（説明） | ||||||
| 内容記述 | 学位論文の要旨, 学位論文本文 | |||||
| 公開者・出版者 | ||||||
| 出版者 | 鹿児島大学 | |||||
| 出版者言語 | ja | |||||
| 公開者・出版者 | ||||||
| 出版者 | Kagoshima University | |||||
| 出版者言語 | en | |||||
| 備考 | ||||||
| 備考言語 | ja | |||||
| 備考 | 指導教員: 小林哲夫, 根建心具 | |||||
| 学位記番号 | ||||||
| 学位記番号 | 理工論第61号 | |||||
| 学位名 | ||||||
| 学位名の言語 | ja | |||||
| 学位名 | 博士(理学) | |||||
| 学位名 | ||||||
| 学位名の言語 | en | |||||
| 学位名 | Doctor of Philosophy in Science | |||||
| 学位授与機関名 | ||||||
| 学位授与機関識別子Scheme | kakenhi | |||||
| 学位授与機関識別子 | 17701 | |||||
| 学位授与機関名の言語 | ja | |||||
| 学位授与機関名 | 鹿児島大学 | |||||
| 学位授与年月日 | ||||||
| 学位授与年月日 | 2012-03-15 | |||||
| 学位授与番号 | ||||||
| 学位授与番号 | 乙理工論第61号 | |||||
