Vietnam Journal of Earth Sciences, 40(2), 208-219, Doi
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dong 1998, tom-tat-kich-ban-bien-doi-khi-hau, LuaChonGiaiPhap, 3959-Article Text-15360-2-10-20110905, Đa dạng sinh học biển Việt Nam - Hiện trạng, các đe dọa và vấn đề quản lý 1520457, 68544-Article Text-174028-1-10-20220705
| 1. Introduction
1 “Non-sulfide zinc” is a term used by pre- vious researchers, referred to a group of ore deposits consisting of Zn-oxidized min- erals, mainly represented by smithsonite, hydrozincite, hemimorphite, sauconite and willemite, which are markedly different from sphalerite zinc ores, typically ex- ploited for zinc (Nicola Mondillo, 2013). * Corresponding author, Email: In the world, from Roman times up to the 18 th century, the non-sulfide Zn-ores, a mixture of silicates and carbonates known as "Lapis Calaminarius", "Calamine", "Gal- mei", or "Galman", in the Latin, French, German, and Polish speaking world respec- tively, were used as the source minerals for the production of brass, a zinc-copper ±tin alloy fairly widespread throughout Europe and the Mediterranean area over the centu- ries (Boni, 2003). However, until the be- ginning of the 20 th century, the production Nguyen Thi Lien and Nguyen Van Pho/Vietnam Journal of Earth Sciences 40 (2018) 209 of zinc metal was focused on non-sulfide ore thanks to the development of solvent- extraction (SX) and electro-winning (EW) processes, and with the modernization of the Wälz technology for the treatment of non-sulfide zinc ores. Non-sulfide zinc de- posits are rapidly becoming an important source of metallic zinc. Since then, scientific studies on non-sulfide zinc ore have also been increased. A number of studies on su- pergene non-sulfide zinc deposits have been carried out and published: Silesia, Southern Poland (Coppola et al., 2007, 2009); Skorpion, Namibia (Borg et al., 2003); Mae Sod, Thailand (Reynold et al., 2003); Shaimerden, Kazakhstan (Boland et al., 2003). Heyl and Bozion (1962), Large (2001) and Hitzman et al. (2003) have proposed the classification of non-sulfide zinc depo- sit. Following Hitzman (2003), non-sulfide zinc deposits are divided into two major geologic types, including supergene and hypogene non-sulfide zinc deposits, in which supergene deposits are the most common type of non-sulfide zinc deposit and are distributed worldwide. Supergene non-sulfide zinc deposits are subdivided into three subtypes: direct replacement, wall-rock replacement, and residual and karst-fill deposits. Hypogene non-sulfide zinc deposits appear to have formed owing to the mixing of a reduced, low-to mod- erate-temperature (80°-200°C), zinc-rich, sulfur-poor fluid with an oxidized, sulfur- poor fluid (Hitzman et al, 2003). In Vietnam, Cho Dien Pb-Zn deposit has been become an object of many studies (Tran Trong Hoa, 2005; Nguyen Van Pho, 2006; Tran Tuan Anh, 2010; Hoa et al., 2010; Anh et al., 2011; Dao Thai Bac, 2012). But studies only describe mineralogical and chemical composition of Pb-Zn ore. There has been no publication on non-sulfide zinc ore in the Cho Dien deposit except the “Wet tropical weathering in Viet Nam” reference book of Nguyen Van Pho (Nguyen Van Pho, 2013). Meanwhile, Cho Dien deposit is a typical example of non-sulfide zinc ore in Vietnam, with ore bodies have complex shape, which were formed in karst cavities. This ore has been exploited for a long time. Up to now, the non-sulfide zinc ore is still the major ore being exploited in Cho Dien. Even in the published study of Hitzman et al. (2003), non-sulfide zinc deposit in Cho Dienis classified as “residual and karst-fill” (Hitzman et al, 2003). This paper presents new study on the mineralogy and geochemistry of Pb-Zn ore, and the composition of ground water to clarify the behavior of zinc element in the oxidation of Pb-Zn ore, and to explain the formation of non-sulfide zinc ore in the Pb- Zn Cho Dien deposit. tải về 1.3 Mb. Chia sẻ với bạn bè của bạn:
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