Lithology, alteration and mineralization of the Fishtie Cu-Co deposit, Zambian Copperbelt

• Material Type: 博士論文
• Title: Lithology, alteration and mineralization of the Fishtie Cu-Co deposit, Zambian Copperbelt
• Author/Editor: MUKUKA, SIMUSOKWE
• Author Heading: MUKUKA, SIMUSOKWE
• Publication, Distribution, etc.: 秋田大学
• Publication Date: 2021-09-24
• Publication Date (W3CDTF): 2021-09-24
• Alternative Title: ザンビア銅鉱化帯フィシテ銅コバルト鉱床の岩相，変質と鉱化作用
• Degree grantor/type: 秋田大学
• Date Granted: 2021-09-24
• Date Granted (W3CDTF): 2021-09-24
• Dissertation Number: 甲第1392号
• Degree Type: 博士（資源学）
• Conferring No. (Dissertation): 甲第1392号
• Text Language Code: eng
• Target Audience: 一般
• Note (General): Fishtie is a copper-rich deposit situated southeast of the Zambian Copperbelt (ZCB), about 30 km north of Mkushi town, close to the international boundary between Zambia and the Democratic Republic of Congo. The deposit was discovered in 2004 by First Quantum Minerals (FQM) Limited through systematic application of soil geochemistry, magnetic survey and drilling. This drilling intersected 300 meters wide by over a kilometre long east-west striking copper orebody similar to the ZCB deposits, but hosted at a higher stratigraphic position in the Katanga Supergroup. The reserves are estimated at 55 Mt of copper at an average grade of 1.04%, occurring as oxide, sulfide and mixed oxide-sulfide ores. Cobalt-rich orebodies are present within the copper orebody, but the two metals show different vertical enrichment and depletion trends.This study was conducted to investigate the following geological characteristics of the Fishtie deposit: (1) the source of the metals, especially copper and cobalt; (2) the source of sulfur; (3) the physical and chemical characteristics of the lithology that are responsible for copper and cobalt mineralization; (4) the timing of mineralization; and (5) the factors controlling the spatial distribution of copper and cobalt metals.Petrographic results of samples from the Grand Conglomérat Formation sitting on the basement rocks shows chalcopyrite preferentially disseminated in chlorite-rich clasts. These clasts weathered from basement mafic rocks and are considered to be the source of copper and cobalt. Copper and cobalt were leached from detrital mafic minerals during hydrothermal alteration and metamorphism, resulting in decomposition of clasts to chlorite and chalcopyrite. Mineral chemistry of alteration minerals suggest that copper and cobalt were liberated as ions during the alteration of chlorite to biotite. The metal ions were transported to the site of deposition through post-folding faults which provided conduits for the oxidizing mineralizing fluids. Copper and cobalt precipitated as chalcocite, bornite, chalcopyrite, cobaltite and carrollite at the boundary of dolostone and reduced beds of alternating siltstone and sandstone. High-grade copper mineralization of chalcopyrite and bornite formed in folded beds of alternating siltstone and sandstone which acted as traps for mineralizing fluids and hydrocarbons. Copper and cobalt mineralization is zoned from deeper level sulfide mineralization to a shallow supergene mineralization of chalcocite, malachite, heteroginite and cobaltoan dolomite.
• DOI: 10.20569/00005829; https://doi.org/10.20569/00005829
• Persistent ID (NDL): info:ndljp/pid/11929564; https://dl.ndl.go.jp/pid/11929564
• Collection: 障害者向け資料
• Collection (Materials For Handicapped People:1): テキストデータ
• Collection (particular): 国立国会図書館デジタルコレクション > デジタル化資料 > 博士論文; https://dl.ndl.go.jp/collections/A00014
• Acquisition Basis: 博士論文（自動収集）
• Date Accepted (W3CDTF): 2021-12-07T08:33:55+09:00
• Date Created (W3CDTF): 2021-11-18
• Format (IMT): PDF
• Access Restrictions: 国立国会図書館内限定公開
• Service for the Digitized Contents Transmission Service: 図書館・個人送信対象外
• Availability of remote photoduplication service: 可
• Periodical Title (URI): http://dx.doi.org/10.20569/00005829; http://hdl.handle.net/10295/00005829
• Data Provider (Database): 国立国会図書館 : 国立国会図書館デジタルコレクション; https://dl.ndl.go.jp