Studies on Rare-earth and Radioactive Minerals of Alkalline Complexes in Brazil.

巴西碱性配合物稀土和放射性矿物的研究。

• 批准号: 01041020
• 负责人: TOKONAMI Masayasu
• 金额: $ 9.28万
• 依托单位: University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for international Scientific Research
• 财政年份: 1989
• 资助国家: 日本
• 起止时间: 1989 至 1990
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01041020/
• 关键词: Mineralogical survey in Brazil; Alkaline rocks; Carbonates; Rare-earth minerals; Weathered rocks; Phosphate and titanium mines in Brazil; Mineral textures; Radioactive minerals

Research surveys of this project were performed for two years of 1989 and 1990, but have actually been continued since 1987. Main subjects of this project are the surveys of minerals which are closely related to alkaline rocks and carbonatite-alkaline complexes in Brazil and understanding their occurrences, mineral assemblages, textures, chemical compositions and so on. Concentration of rare-earth elements are characteristic in the complexes, and radioactive elements are often accompanied in minerals. Therefore, their minerals are also intersted as a natural analogue for the basic research of solidification and stabilities of radioactive wasted materials.In this project, survey and collection of rocks minerals were carried out in the carbonatitealkaline complexes which dot Brazilian shield along the lines from south to north. The main surveyed areas and collected rocks and minerals are summarized as follows : (1) fresh carbonatites and jacupirangite, and their thermal metamorphic rocks … More at the boundaries of carbonatites and jacupirangites at mines near Cajati in the state of Santa Catarina ; (2) Alkaline rocks such as caldasite which is extraordinarily enriched in Zr, phonolite, tinguite, rocks which include radioactive elements, ultrabasic rocks mainly composed of magnetite and so on, at Pocos de Caldas at the boundary of both states of Sao Paulo and Minas Gerais ; (3) Minerals of perovskite, anatase, pyrochlore and so on which are obtained from carbonatite-alkaline complexes at Araxa and Tapira in Minas Gerais ; (4) Weathered soil of carbonatie-alkaline complexes which are concentrated by such rare-earth elements as La and Ce at Catalao in the south of state of Goias ; (5) Ultrabasic rocks of which main components are crysotile, graphite and so on at Minacu of Minas Gerais ; (6) Zircon bearing alkaline rocks at Peixe in the State of Tocantins ; and (7) Nephelin-syenite and sodalite-nephelin syenite in south Bahia and in Para. The ages of intrusion of above alkaline rocks estimated in the range from 70-130Ma.All of collected samples are difficult to obtain in Japan and indispensable specimens in order to study the origin of carbon, minerallization processes of phosphate and rare-earth minerals, weathering processes, and description of varieties of minerals, and so on. The textures, constituent minerals, and their chemical compositions of some of above specimens have already been described by observations of optical microscope, X-ray diffraction apparatus, scanning electron microscope and so on, and further works will be continued in future.We wish to thank Brasilian scientists, many geologists in mines which we visited, for their colaborations and helps. We feel deep mortification at Professor Kenkichi FUJIMORI's sudden decease by cancer in July of 1990, who strongly promoted this project as one of investigators of this project. Less

该项目的研究调查在1989年和1990年进行了两年，但实际上自1987年以来一直在继续。该项目的主要内容是对巴西碱性岩和碳酸盐-碱性杂岩密切相关的矿物进行调查，了解其产状、矿物组合、结构、化学成分等，杂岩中稀土元素富集是其特征，矿物中常伴有放射性元素。本项目对巴西地盾沿着南北走向分布的碳酸盐-碱性杂岩体进行了岩石矿物的调查和采集。主要研究区和采集的岩石矿物有：（1）新鲜碳酸岩和绿柱石及其热变质岩石 ...更多信息 （2）位于圣保罗州和米纳斯卡贾蒂州交界处的波科斯德卡尔达斯的碱性岩石，如异常富集Zr的Caldasite、响岩、硬硅钙石、含放射性元素的岩石、主要由磁铁矿组成的超基性岩等;（3）米纳斯吉拉斯的阿拉克萨和塔皮拉碳酸盐-碱性复合体中钙钛矿、钙钛矿、烧绿石等矿物：（4）戈亚斯州南部的卡塔劳碳酸盐-碱性复合体风化土中富集La、Ce等稀土元素;（5）米纳斯吉拉斯米纳库的超基性岩，主要成分为隐长石、石墨等，（6）托坎廷斯州佩克斯的含锆石碱性岩;和（7）钠长石正长岩和方钠石-巴伊亚南部和帕拉的霞石正长岩。所有采集的样品在日本都很难获得，是研究碳的来源、磷酸盐和稀土矿物的成矿过程、风化过程以及矿物种类描述等不可缺少的标本。通过光学显微镜、X射线衍射仪、扫描电镜等观察，对上述部分样品的矿物组成、化学成分等进行了描述，今后还将继续进行进一步的工作，在此感谢巴西科学家和我们所访问矿山的许多地质学家的合作和帮助。我们对藤森健吉教授于1990年7月因癌症突然去世深感羞愧，他作为该项目的研究者之一，大力推动了该项目。少

项目成果

芳賀 信彦: "Araxa(ブラジル)におけるカ-ボナタイトの構成鉱物" 日本鉱物学会1989年年会講演要旨集. 83 (1989)

Nobuhiko Haga：“阿拉沙（巴西）碳酸岩的组成矿物”日本矿物学会 1989 年年会摘要 83 (1989)。

豊田 和弘: "機器光量子放射化分析法による標準岩石試料およびカ-ボナタイト風化土壌試料の分析" 核理研研究報告. 22. 117-122 (1989)

Kazuhiro Toyoda：“通过仪器光子活化分析对标准岩石样品和碳酸盐岩风化土壤样品进行分析”核研究报告 22. 117-122 (1989)。

堀内 弘之: "ブラジル・タッピ-ラのグリメライト中のCaーZrーTiーO系鉱物" 日本鉱物学会1989年年会講演要旨集. 61 (1989)

Hiroyuki Horiuchi：“来自巴西塔皮拉的硅藻土中的 Ca-Zr-Ti-O 矿物”日本矿物学会 1989 年年会摘要 61 (1989)。

湊 秀雄: "兵庫県社町周辺の斜プチロル沸石の産状と鉱物学的性質、特に島根県玉造産のものとの比較" 鉱物学雑誌. 19. 193-208 (1990)

Hideo Minato：“兵库县沙町周围斜发醇沸石的产状和矿物学性质，特别是与岛根县玉造的比较”《矿物学杂志》19. 193-208 (1990)。

Nobuhiko HAGA: "Constituent Minerals in Carbonatites in Araxa (Brazil)." Collected Abstracts of Mineralogical Society of Japan. 83 (1989)

Nobuhiko HAGA：“阿拉沙（巴西）碳酸岩中的矿物成分。”