Formation Mechanisms and Formation Environment of Seaflor Hydrothermal Ore Deposits

Seaflor热液矿床形成机制及形成环境

• 批准号: 06303001
• 负责人: ISHIKAWA Yohei
• 金额: $ 3.52万
• 依托单位: Akita University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Co-operative Research (A)
• 财政年份: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-06303001/
• 关键词: Seafloor hydrothermal ore deposits; Volcanogenic massiv sulfide deposits; Kuroko deposits; Magmatisum and Mineralization; Hydrothermal alteration; Fluid inclusion; Isotope geology; Chemical composition of minerals

The purposes of this Scientific Research Project are to solve the tectonic situation and depositional mechanism of colcanogenic massive sulfide ore deposits. The main objects of the ore deposits are one of the most representative Kuroko deposits of the Miocene age and the seafloor hydrothermal deposits of modern age. Descriptive geology on ores and related igneous rocks and up-to-date geochemical investigation are indispensable and the combination of both research procedures makes possible for the generalized earth scientific interpretation on ore genesis.In this study, the significance of geology and metal resources are examined first for the Hokuroku district in Akita Prefecture where the large scale Kuroko deposits were primarily developed. The second object is the presentatation for some volcano-stratigraphic points the area on the volcanogenic background of the Kuroko deposits.The siliceous mound in the Kosaka-Uchinotai deposit, one of the typical Kuroko deposits, are precisely in … More vestigated for the mode of occurrences. Geochemical characteristics are examined for ores from some Kuroko-and Besshi-type volcanogenic massive sulfide deposits, and the change of ore textures are studied from primary to successive diagenetic stages. The investigation of stable isotopic geology revelas that the carbonates from the Kosaka-Uwamuki deposit are formed by the reaction with hydrothermal fluid and carbonate in biogenic origin.Researches on seafloor hydrothermal deposits in modern age reveals that magmatic activities are important as the origin of hydrothermal fluids in the western Pacific region. Besides, seafloor sediments of the modern Kuroko-type deposits in the Okinawa Troughare investigated for the chemical and mineralogical compositions. In the seafloor hydrothermal deposits, the textures and structures of ores and the compositions of minirals are representing the generation circumstances, and those of Miocene Kuroko ores could be give some valuable hints for the consideration on primary features, preservation of ores and diagenetic processes. Less

本科研项目旨在解决火山成因块状硫化物矿床的构造状况和沉积机制。矿床的主要对象为中新世最具代表性的黑岩矿床之一和现代海底热液矿床。矿石及相关火成岩的描述地质学和现代地球化学调查是不可缺少的，两者的结合使对矿床成因的广义地球科学解释成为可能。本文首先考察了秋田县北陆地区的地质和金属资源意义，该地区主要发育大型黑陆矿床。第二个目标是在黑子矿床的火山成因背景下，对该地区的一些火山地层点进行介绍。作为典型的黑子矿床之一，大阪-内野台矿床中的硅质丘恰好处于其赋存模式的研究中。研究了黑子-别石型火山岩块状硫化物矿床矿石的地球化学特征，研究了从原生到连续成岩阶段矿石结构的变化。稳定同位素地质研究表明，小坂-宇和木矿床碳酸盐是由热液与碳酸盐反应形成的，具有生物成因。近代海底热液沉积研究表明，岩浆活动是西太平洋地区热液流体的重要来源。此外，对冲绳海槽现代黑古型海底沉积物的化学和矿物组成进行了研究。在海底热液矿床中，矿石的结构构造和矿物组成代表了成矿环境，中新世黑岩矿石的结构构造和矿物组成可为考虑矿石的原始特征、保存和成岩过程提供有价值的线索。少

项目成果

石川 信明: "秋田市北部仁別鉱化帯の金絋作用に関する地球化学的研究" 秋田大学鉱山学部研究報告. 16. 1-11 (1995)

石川伸明：“秋田市北部二别矿化带金溪活动的地球化学研究”秋田大学矿业学院研究报告16. 1-11（1995）。

堀越 叡: "北海道東部の中新世火山のテクトニクス" 資源地質. 44. 81-91 (1994)

堀越彰：“北海道东部中新世火山的构造”资源地质学 44. 81-91 (1994)。

浦辺 徹郎: "西大西洋の島孤・縁海系の海底熱水活動-現在と過去" 地学雑誌. 104. 438-448 (1995)

Tetsuro Urabe：“西大西洋岛屿和边缘海的海底热液活动 - 现在和过去”地质杂志 104. 438-448 (1995)。

Shibata,Y.: "Chemical composision of Fe-Ni metal and phosphate minerals in Yamato-82094 carbonaceous chondrite" Proceedings of the NIPR Symposium on Antarctic Meteorites. No.7(印刷中). (1994)

Shibata, Y.：“Yamato-82094 碳质球粒陨石中铁镍金属和磷酸盐矿物的化学成分”南极陨石 NIPR 研讨会论文集第 7 号（1994 年出版）。

水田 敏夫: "小笠原水曜火山カルデラ内の銅に富む熱水性チムニ-鉱石" JAMSTEC深海研究. 10号. 75-87 (1994)

Toshio Mizuta：“小笠原星期三火山破火山口中富含铜的热液烟囱矿石”JAMSTEC 深海研究 (1994)。