Concentration Mechanism of Base Metal Elements in Vein-Type Deposits of Tertiary Age

第三纪脉状矿床贱金属元素富集机制

• 批准号: 60540518
• 负责人: SHIKAZONO Naotatsu
• 金额: $ 1.47万
• 依托单位: University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1985
• 资助国家: 日本
• 起止时间: 1985 至 1986
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-60540518/
• 关键词: Ore deposits; Vein-type deposits; Gold-silver deposits; Stable isotopes; Fluid inclusions; Origin of elements; Hydrothermal alteration; Water

The purposes of this project are to clarify concentration mechanism of base metal elements and environmental conditions for epithermal vein-type deposits which are distributed in Tertiary volcanic regions in Japan.For these purposes we have studied several aspects of these deposits. They are: (1) geology, (2) mineralogy, (3) stable isotopes, (4) fluid inclusions, and (5) hydrothermal alterations.main results obatained are as follows:(1) Geologic environments of gold-silver mining districts (western part of Izu peninsula, Yonezawa district of Fukushima Prefecture, Southwestern part of Hokkaido) have been eleucidated, (2) Sulfur, carbon and oxygen isotopic compositions of base metal and gold-silver mining districts (Green tuff region, Izu, Kyushu) have been obtained, (3) Fluid inclusions in gold-silver deposits (Seigoshi, Yatani deposits) have been studied. (4) Chemical compositions of ore minerals (e.g. Au-Ag minerals, sphalerite) have been obtained, (5) Hydrothermal alteration in gold-silver mining district (Seigoshi in Izu peninsula) has been studied.Using these data from (1) to (5), the most likely model for hydrothermal system accompanied by vein-type ore deposition was constructed. This model was compared with that for active geothermal system. The differrences in the characteristic features of epithermal vein-type deposits and active geothermal system were different behavior of gas-liquid-rock interactions.Further theoretical and experimental works on the concentration mechanism of base metal elements in vein-type deposits are necessary.

本项目旨在阐明分布于日本第三纪火山岩区的浅成热液脉型矿床的贱金属元素富集机制和环境条件，为此，我们对这类矿床的几个方面进行了研究。它们分别是：（1）阐明了各金银矿区（伊豆半岛西部、福岛县米泽地区、北海道西南部）的地质环境;（2）测定了各金银矿区（九州伊豆绿凝灰岩地区）和贱金属的硫、碳、氧同位素组成;（3）研究了各金银矿床（绿色越、八谷矿床）的流体包裹体。(4)（5）研究了伊豆半岛的清越地区的金银矿区的热液蚀变，利用（1）~（5）的数据，建立了最可能的热液系统伴脉型矿床模式。并与活动地热系统的模型进行了比较。浅成热液脉型矿床与活动地热系统的特征不同在于气-液-岩相互作用的不同表现，需要进一步开展脉型矿床中贱金属元素富集机理的理论和实验研究。

项目成果

Masaaki Shimizu: Mineralium Deposita. 20. 314-320 (1985)

清水正明：矿物沉积物。

Naotatsu Shikazono: Mining Geology. 36. 411-424 (1986)

Naotatsu Shikazono：采矿地质学。

Naotstsu Shikazono: "Ag/Au total production ratio and Au-Ag minerals from vein-type and disseminated-type deposits in Japan" Mining Geology. 36. 411-424 (1986)

Naotstsu Shikazono：“日本脉型和浸染型矿床的银/金总产量比和金银矿物”采矿地质学。

Naotatsu Shikazono: "Comparison of temperatures estimated from electrum-sphalerite-pyrite-argentite assemblage and filling temeratures of fluid inclusions from epithermal Au-Ag vein-type deposits in Japan." Economic Geology. 80. 1415-1424 (1985)

Naotatsu Shikazono：“金银矿-闪锌矿-黄铁矿-银矿组合估算的温度与日本浅成热液金银矿脉型矿床的流体包裹体充填温度的比较。”

Ryo Matsumoto: "Chemistry, carbon and oxygen isotope ratios, and origin of deep-sea carbonates at sites 438, 439, and 584: Inner slope of the Japan trench'" Initial Reports of the Deep Sea Drilling Project. LXXXVII. 669-678 (1985)

Ryo Matsumoto：“438、439 和 584 号地点的深海碳酸盐的化学、碳和氧同位素比以及起源：日本海沟的内坡”，深海钻探项目的初步报告。