湖北徐家山锑矿床地球化学和成矿机理研究

　　湖北省通山县的徐家山锑矿床赋存于上震旦统灯影组和陡山沱组的海相碳酸盐岩中，该矿床是华南锑矿带内典型代表性锑矿之一，也是湖北最具经济价值的锑矿床。本论文以该矿床为研究对象，在系统整理前人工作的基础上，进行了深入细致的野外地质考察和系统采样，选取有代表性的样品，运用流体地球化学、元素地球化学、同位素地球化学（C、O、Sr、S、Pb、Sm-Nd）等方法手段，对其成矿流体来源、成矿物质来源、成矿时代、矿床成因等主要矿床学问题进行了系统研究，探讨了该矿床的成矿机理，并对华南锑矿带内上震旦统锑资源潜力进行了初步评价。本论文主要取得以下几点认识： 1）通过对该矿床成矿期脉石矿物（石英、重晶石和方解石）中包裹体镜下观察、显微测温和激光拉曼探针分析，表明该矿床为典型的中低温（150～200℃）热液锑矿床，其热液属NaCl + H2O + CO2 ± N2型，具低盐度（3～6% NaCl）和中等密度（0.90～0.96 g/cm3）特征。结合氢、氧、锶、铅同位素等研究结果，进一步推断这种成矿流体主要来源于经深部循环演化的大气降水，不支持其主要来源于岩浆期后热液的观点。 2）该矿床成矿前和成矿期方解石碳、氧同位素研究结果，表明成矿流体中的溶解碳以H2CO3为主，该流体与围岩发生水－岩相互作用是导致成矿期方解石和辉锑矿沉淀的主要机制。结合方解石的稀土元素地球化学研究，可推断该矿床的两期方解石为同源不同期的产物。 3）微量元素、碳、氧、硫同位素研究结果，表明徐家山矿床的成矿物质与赋矿围岩具有亲缘性；其中最主要的矿石矿物—辉锑矿，其硫同位素组成（+11.2‰～+14.4‰）相对较高（平均值可能在华南锑矿带内最高）、极其均一，且塔式效应明显等为特征，指示该矿的赋矿围岩—震旦纪海相地层是硫的唯一来源。 4）对徐家山锑矿床首次利用锶、铅同位素示踪其成矿物质来源。利用铅同位素示踪手段，首次明确提出该锑矿床存在两个矿源层，部分成矿物质来自赋矿围岩，部分成矿物质来自下伏基底地层，突破了前人对成矿物质仅来源于赋矿围岩的传统认识；并从锶同位素角度，进一步论证了下伏的中元古界冷家溪群基底是成矿元素锑的重要提供者。 5）首次对徐家山矿区成矿期方解石的Sm-Nd同位素组成进行了测定，并初步获得三条等时线年龄（323Ma、348Ma和402Ma）。结合该矿辉锑矿的正常铅模式年龄及成矿地质背景，可推断出该矿床应形成于加里东期。该结论否定了前人燕山期成矿的观点，为重新认识该矿的矿床成因和成矿机理提供新的契机。 6）徐家山锑矿床的成矿时代与那些江南古陆中赋存于前寒武系的锑（和/或金）矿床一致，其成矿流体特征与华南锑矿带其它典型锑矿床相似，揭示出华南锑矿带内不同地段、不同层位产出的锑矿床存在某种共性，这有助于揭示我国华南锑矿带不同锑矿床之间的内在联系以及该矿带锑大规模成矿的机制。 7）根据前人和本文的研究成果，重新厘定了徐家山锑矿床的成因类型，明确提出该锑矿为沉积－改造型矿床，层控特征非常明显。 8）初步评估华南地区上震旦统中锑矿的找矿潜力。认为华南锑矿床带中上震旦统，尤其是鄂南、赣西北、湘西等地的该套地层，锑资源潜力巨大。华南锑矿带中的上震旦统有可能成为我国将来找锑矿取得突破的重要层位之一。

The Effect of Impurities on the Electrodeposition of Zinc from Zinc Sulfate Solution Containing Antimony.

It has been proven by research and years of experience, that before electrolytic zinc is possible, the electrolyte, as zinc sulfate solution must be prepared as pure as is economical. In other words, the ideal electrolyte must only be a solution of one metal - zinc. Every other metal and carbon must be excluded if good recovery and a firm deposit is to be obtained.

Geological and geochemical characteristics of the Tersang gold deposit, Malaysia: implications for genesis and gold exploration

The Central gold belt of peninsular Malaysia comprises a number of gold deposits located in the east of the N-S striking Bentong-Raub Suture Zone. The Tersang gold deposit is one of the gold deposits in the gold belt and hosted in sandstone, rhyolite and breccia units. The deposit has an inferred resource of 528,000 ounces of gold. The geochronology of the Tersang deposit has been newly constrained by LA ICP-MS U-Pb zircon dating. The maximum depositional age of the host sedimentary rocks ranges from Early Carboniferous to Early Permian (261.5 ± 4.9 Ma to 333.5 ± 2.5 Ma) for the host sandstone and Late Triassic for the rhyolite intrusion (218.8 ± 1.7 Ma). Textural characteristics of pyrite have revealed five types including (1) Euhedral to subhedral pyrite with internal fracturing and porous cores located in the sandstone layers (pyrite 1); (2) Anhedral pyrite overgrowths on pyrite 1 and disseminated in stage 1 vein (pyrite 2); (3) Fracture-filled or vein pyrite located in stages 1 and 2 vein (pyrite 3); (4) Euhedral pyrite with internal fractures also located in stage 2 vein (pyrite 4); and (5) Subhedral clean pyrite located in the rhyolite intrusion (pyrite 5). Based on pyrite mapping and spot analyses, two main stages of gold enrichment are documented from the Tersang gold deposit. Gold in sandstone-hosted pyrite 1 (mean 4.3 ppm) shows best correlation with Bi and Pb (as evidenced on pyrite maps). In addition, gold in pyrite 3 (mean 8 ppm) located in stage 2 vein shows a good correlation with As, Ag, Sb, Cu, Tl, and Pb. In terms of gold exploration, we suggest that elements such as As, Ag, Sb, Cu, Tl, Bi, and Pb associated with Au may serve as vectoring tools in gold exploration. Our new geological, structural, geochemical and isotopic data together with mineral paragenesis, pyrite chemistry and ore fluid characteristics indicate that the Tersang gold deposit is comparable to a sediment-hosted gold deposit. Our new genetic model suggests deposition of the Permo-Carboniferous sediments followed by intrusion of rhyolitic magma in the Late Triassic. At a later stage, gold mineralisation overprinted the rhyolite intrusion and the sandstone.

Table 2 Analytical data of the samples by the "Dipole CHIM" at the Yingezhuang gold deposit

CHIM method involves extracting metal ions of electromobile forms in either anodes or cathodes, facilitated by a man-made electric field. This paper presents two newly developed CHIM alternatives that are electrified by a low voltage dipole. The firstly improved technique enables cationic ions to be extracted in a single cathode, whereas the secondly improved technique allows both anionic and cationic species to be extracted simultaneously in an anode and in a cathode. Compared with the traditional CHIM methods, the innovative techniques developed in this paper are characterized by simple instrumentation, low cost and easy operation in field, and in particular enables simultaneous extraction of anionic and cationic species of elements, from which more information can be derived with higher extraction efficiency. Field tests at several well-known mine areas in China confirm the effectiveness and efficiency of the new techniques in exploring for deeply buried ore bodies.

Raman spectroscopic study of the antimony containing mineral partzite Cu2Sb2(O,OH)7

Raman spectroscopy of the mineral partzite Cu2Sb2(O,OH)7 complimented with infrared spectroscopy were studied and related to the structure of the mineral. The Raman spectrum shows some considerable complexity with a number of overlapping bands observed at 479, 520, 594, 607 and 620 cm-1 with additional low intensity bands found at 675, 730, 777 and 837 cm-1. Raman bands of partzite in the spectral region 590 to 675 cm-1 are attributable the ν1 symmetric stretching modes. The Raman bands at 479 and 520 cm-1 are assigned to the ν3 antisymmetric stretching modes. Raman bands at 1396 and 1455 cm-1 are attributed to SbOH deformation modes. A complex pattern resulting from the overlapping band of the water and OH units is found. Raman bands are observed at 3266, 3376, 3407, 3563, 3586 and 3622 cm-1. The first three bands are assigned to water stretching vibrations. The three higher wavenumber bands are assigned to the stretching vibrations of the OH units. It is proposed that based upon observation of the Raman spectra that water is involved in the structure of partzite. Thus the formula Cu2Sb2(O,OH)7 may be better written as Cu2Sb2(O,OH)7 •xH2O

A Raman spectroscopic study of the antimony mineral klebelsbergite Sb4O4(OH)2(SO4)

Many minerals based upon antimonite and antimonate anions remain to be studied. Most of the bands occur in the low wavenumber region, making infrared spectroscopy difficult to use. This problem can be overcome by using Raman spectroscopy. Raman spectra of the mineral klebelsbergite Sb4O4(OH)2(SO4) were studied, and related to the structure of the mineral. Raman bands observed at 971 cm-1 and a series of overlapping bands are observed at 1029, 1074, 1089, 1139 and 1142 cm-1 are assigned to the SO42- ν1 symmetric and ν3 antisymmetric stretching modes. Two Raman bands are observed at 662 and 723 cm-1 and assigned to the SbO ν3 antisymmetric and ν1 symmetric stretching modes. The intense Raman bands at 581, 604 and 611 cm-1 are assigned to the ν4 SO42- bending modes. Two overlapping bands at 481 and 489 cm-1 are assigned to the ν2 SO42- bending mode. Low intensity bands at 410, 435 and 446 cm-1 may be attributed to OSbO bending modes. The Raman band at 3435 cm-1 is attributed to the OH stretching vibration of the OH units. Multiple Raman bands for both SO42- and SbO stretching vibrations support the concept of the non-equivalence of these units in the klebelsbergite structure. It is proposed that two sulphate anions are distorted to different extents in the klebelsbergite structure.

Equitable mortgage by deposit of a Certificate of Title

In Theodore v Mistford Pty Ltd [2005] HCA 45, the High Court considered certain principles governing the creation of an equitable mortgage by the deposit of a title deed as first developed by the English courts of equity with respect to old system conveyancing. The decision will be of interest to Queensland practitioners as it concerned the application of these equitable principles to Torrens land regulated by the provisions of the Land Title Act 1994 (Qld) and, in particular, the operation of s 75 of the Land Title Act 1994 (Qld) which provides: (i) An equitable mortgage of a lot may be created by leaving a certificate of title with the mortgagee (ii) Subsection (1) does not affect the ways in which an equitable mortgage may be created.

Removal of toxic arsenic and antimony from groundwater Spiro Tunnel Bulkhead in Park City Utah using colloidal iron hydroxide : comparison with reverse ssmosis

Verification testing of two model technologies in pilot scale to remove arsenic and antimony based on reverse osmosis and chemical coagulation/filtration systems was conducted in Spiro Tunnel Water Filtration Plant located in Park City, Utah, US. The source water was groundwater in abandoned silver mine, naturally contaminated by 60-80 ppb of arsenic and antimony below 10 ppb. This water represents one of the sources of drinking water for Park City and constitutes about 44% of the water supply. The failure to remove antimony efficiently by coagulation/filtration (only 4.4% removal rate) under design conditions is discussed in terms of the chemistry differences between Sb (III, V) and As (III, V). Removal of Sb(V) at pH > 7, using coagulation/filtration technology, requires much higher (50 to 80 times) concentration of iron (III) than As. The stronger adsorption of arsenate over a wider pH range can be explained by the fact that arsenic acid is tri-protic, whereas antimonic acid is monoprotic. This difference in properties of As(V) and Sb(V) makes antimony (V) more difficult to be efficiently removed in low concentrations of iron hydroxide and alkaline pH waters, especially in concentration of Sb < 10 ppb.