Sulfur Isotope Study on Hg and Sb Deposits in Japan

Abstract. Sulfur isotope ratios of cinnabar from Hg deposits and stibnite, jamesonite and berthierite from Sb deposits in Japan are examined in order to understand metallogeneses of Hg and Sb deposits in Japanese island arcs. The studied Hg and Sb deposits include the Hg deposit at Yamato‐suigin (Honshu) and the Sb deposit at Ichinokawa (Shikoku) in the Southwest Japan arc. In addition, Hg deposits including Itomuka and Ryushoden in central Hokkaido and Hg and Sb mineralizations in Northeast Japan arc are examined. The δ³⁴S values of cinnabar from the Hidaka‐Kitami district, central Hokkaido, including the Itomuka and Ryushoden deposits range widely, from ‐10 to +16 %o, the highest values encountered at the Samani deposit. The δ³⁴S values of cinnabar from other areas in Japan range from ‐12 to +5 %o, having δ³⁴S values higher than +2 %o from southwestern Hokkaido (Meiji deposit), Shikoku (Suii deposit) and Kyushu (Hasami and Yamagano deposits). On the other hand, the δ³⁴S values of stibnite from all areas in Japan range from ‐14 to +5 %o, having positive δ³⁴S values higher than +2 %o up to +5 %o from southwestern Hokkaido (Yakumo, Toyotomi and Teine deposits) and eastern‐central Honshu (Hachiman and Daikoku deposits). The variation in δ³⁴S values of Hg and Sb deposits may reflect the variation in δ³⁴S values of country rocks or variation in mixing ratio of sulfur extracted from the country rocks, sulfur derived from seawater sulfate, and sulfur derived from magmatic emanations. The relatively high δ³⁴S values of cinnabar and stibnite higher than +2 %o from southwestern Hokkaido, eastern‐central Honshu and Kyushu are probably caused by contribution of volcanic emanation from arc magmas having positive σδ³⁴S values, whereas the positive δ³⁴S values of cinnabar higher than +2 %o from Suii deposit in Shikoku may be attributed to structurally substituted sulfate in limestone country rocks and/or sulfur derived from seawater sulfate. However, the wide range of the δ³⁴S values of cinnabar from the Hidaka‐Kitami district, central Hokkaido, is difficult to explain at this moment. Other relatively low, negative δ³⁴S values of cinnabar and stibnite, berthierite from other areas in Japan may be attributed to 1) incorporation of isotopically light sedimentary sulfur or sulfur derived from ilmenite‐series silicic magma, or 2) less contribution of volcanic emanation from arc magmas having positive σδ³⁴S values.     

压实度对铁盐稳定化砷、锑污染土特性的影响及机制研究

压实度是影响铁盐稳定化砷(As)、锑(Sb)污染土环境岩土工程特性的主要因素之一。通过测定不同压实度铁盐稳定剂(PFSC)稳定化As、Sb污染土无侧限抗压强度(UCS)、As和Sb浸出浓度、渗透系数kw,研究了压实度对PFSC稳定化As、Sb污染土环境岩土工程特性的影响规律。通过工业CT扫描、X射线光电子能谱(XPS)明确了稳定化土微观孔隙特征、元素价态随压实度的变化规律。As的浸出浓度随着压实度的提高先降低后略微上升,压实度为93%时,As的浸出浓度最低;Sb的浸出浓度随着压实度的提高而降低,压实度大于85%后趋于平稳。压实度由75%提高至96%,稳定化土UCS由4.26 kPa增大至43.78 kPa。压实度由80%提高至96%,稳定化土k_w由1.33×10^–7 m/s降低至2.81×10^–9 m/s。工业CT扫描结果表明,随着压实度的提高,土体逐渐紧实,土体孔隙度由7.54%降低至5.30%。As、Sb和Fe的XPS分析结果表明,压实度增高促使As(Ⅴ)、Sb(Ⅴ)和Fe(Ⅲ)分别向As(Ⅲ)、Sb(Ⅲ)和Fe(Ⅱ...     

Evaluation of Major to Ultra Trace Element Bulk Rock Chemical Analysis of Nanoparticulate Pressed Powder Pellets by LA‐ICP‐MS

An efficient, clean procedure for the measurement of element mass fractions in bulk rock nanoparticulate pressed powder pellets (PPPs) by 193 nm laser ablation ICP‐MS is presented. Samples were pulverised by wet milling and pelletised with microcrystalline cellulose as a binder, allowing non‐cohesive materials such as quartz or ceramics to be processed. The LA‐ICP‐MS PPP analytical procedure was optimised and evaluated using six different geological reference materials (JP‐1, UB‐N, BCR‐2, GSP‐2, OKUM and MUH‐1), with rigorous procedural blank quantification employing synthetic quartz. Measurement trueness of the procedure was equivalent to that achieved by solution ICP‐MS and LA‐ICP‐MS analysis of glass. The measurement repeatability was as low as 0.5–2% (1s, n = 6) and, accordingly, PPP homogeneity could be demonstrated. Calibration based on the reference glasses NIST SRM 610, NIST SRM 612, BCR‐2G and GSD‐1G revealed matrix effects for glass and PPP measurement with NIST SRM 61×; using basalt glasses eliminated this problem. Most significantly, trace elements not commonly measured (flux elements Li, B; chalcophile elements As, Sb, Tl, In, Bi) could be quantified. The PPP‐LA‐ICP‐MS method overcomes common problems and limitations in analytical geochemistry and thus represents an efficient and accurate alternative for bulk rock analysis.     

广东嵩溪银(锑)矿床地质地球化学及成矿模式

嵩溪银(锑)矿床赋存于下侏罗统金鸡组,矿石具脉状、角砾状构造,含大量硫盐矿物.围岩蚀变包括硅化、黄铁矿化、碳酸盐化、绢云母化及青磐岩化.主成矿阶段温度集中于150～260℃.硫、氢、氧同位素显示成矿物质主要来自深源和围岩,成矿流体既有岩浆水也有大气降水参与,成矿作用与早白垩世石英斑岩有关,嵩溪银(锑)矿床为与陆相次火山岩有关的浅成低温热液矿床.     

广西铅锑矿冶炼区表层土壤重金属污染的分布规律

为了解铅锑冶炼活动对周边土壤的污染情况,通过实地采样调查和室内样品分析,对河池铅锑矿冶炼区周边土壤中重金属含量的空间分布规律进行了分析,并对该区重金属污染情况进行评价。结果表明:冶炼区表层土壤受到较高含量的Sb、Pb、Zn污染,As、Cd和Cu也有一定程度的污染。土壤中的w(Sb)、w(Pb)和w(Zn)分别为195～2034 mg/kg、259～2261 mg/kg和365～1033 mg/kg,分别达到背景值的4.8～33.3倍、3.4～29.7倍和1.4～3.9倍。冶炼区表层土壤中的重金属含量与冶炼厂的远近关系密切,Sb、As和Pb在0～400 m范围急剧衰减,400 m范围内Sb、As和Pb分别衰减了92.5%、95%、93.7%。在400～2400 m的2000 m区间Sb、As和Pb分别衰减了64.4%、80.9%、52.1%。Cd在200 m范围内衰减了88.7%,在200～2400 m范围没有显著变化。Sb、As、Cd和Pb在400～2400 m范围呈缓慢衰减,使得重金属的影响可达很远。Sb和Pb的衰减趋势高度相似,这对于Pb-Sb的全球迁移具有相关的意义。     

云南巍山笔架山锑矿床辉锑矿稀土微量元素特征及其矿床成因意义

以笔架山锑矿床为研究对象,在矿床精细解剖基础上,利用辉锑矿金属矿物ICP-MS分析,指示成矿流体来源和性质。研究结果显示,辉锑矿轻稀土强烈富集,分馏程度高,Tb、Dy、Eu呈显著的正异常,显著的正异常稀土配分模式,与喜马拉雅期富碱斑岩的稀土配分模式具有相似性。此外,辉锑矿矿物以其强Sr和Ba正异常的微量元素特征,与喜马拉雅期富碱斑岩中高含量Sr和Ba的特征一致。辉锑矿矿物的Y/Ho比值变化较大,其比值随辉锑矿的氧化程度增大和产出海波高度增高而逐渐增大。对比不同流体系统的Y/Ho比值发现氧化程度较大和海拔较高的辉锑矿Y/Ho比值与现代海水的Y/Ho比值接近,氧化程度较低的辉锑矿Y/Ho比值与莲花山岩体Y/Ho比值接近,指示成矿流体可能是岩浆与大气降水不同程度的混和。H-O同位素研究显示出成矿热液来源于岩浆水和大气降水的混合。Pb同位素显示壳、幔源多源铅的特征。S同位素表明辉锑矿的S主要为生物与岩浆热液来源硫的混合。综合研究认为,该矿床是一个受层间构造破碎带控制的位于岩浆远端的低温热液矿床。      

武宁县石渡锑矿控矿地质因素及成矿机理

本语文系统地介绍了武宁县石渡锑矿的基本地质特征,并结合大量的实际地质资料,对矿床的控矿地质因素进行了探讨,认为石渡锑矿不但受区域成矿环境和地层层位及岩石 控制,同时控矿构造对矿体空间分布及其形态产状也起重要控制作用。叙述了构造演化与成矿的关系,阐明了控矿构造形式及控矿构造类型。最后对锑矿的成矿机理进行了探讨。     

多目标生态地球化学调查土壤样品中砷硒锑有效态分析方法的商榷

以0．10mol／L NaH2PO4和0．50mol／L NaHCO3为浸提剂，试验了其对土壤样品中As、Se、Sb的浸提效果；以氢化物发生-原子荧光法(HG-AFS)测定了浸提液中As、Se、Sb的含量。方法在武汉、宁镇测区应用试验表明：采用0．50mol／L的NaHCO3为As、Se、Sb的有效态浸提剂，以HG—AFS法测定其含量的方案可行，检出限分别为：0．006mg／kg、0．001mg／kg、0．002mg／kg。精密度试验，6个标准样品的RSD(n=12)As、Se、Sb均≤10．15％。     

粤东宝山银（锑）矿床地质特征和成因

粤东宝山大型银（锑）矿床产于早侏罗世火山－沉积地层中，银、硫（锑）化物矿体呈脉状，沿下侏罗统金鸡组上段碳质页岩和粉砂岩的层间断裂中分布。矿床深部具青磐岩化蚀变，中部以黄铁矿化、硅化、碳酸盐化主，上部以硅化为特征。矿区自西向东锑矿化减弱，银矿化增强，在垂直方向上，６０ｍ标高之上为锑矿化富集带，０ｍ标高以下为银矿化富集带，研究表明，区域早侏罗世火山－沉积地层可能是矿源层，矿床是与燕山中一晚期火山－次火     

越南广宁省晋磨锑矿床流体包裹体和氢氧同位素地球化学研究

晋磨锑矿床位于印支地块和华南地块碰撞界线的边缘、金沙江-红河断裂带的南段东侧,属于华南地块。对矿床开展的石英流体包裹体均一法测温、气液相成分测试和氢氧同位素测试分析表明,流体包裹体液相成分以Ca2+、Na+、K+、SO2-4、Cl-和F-为主,气相成分以H2O与CO2为主。流体包裹体均一温度在138℃~308℃之间,平均值为208℃,盐度在0.3%~4.0%之间,平均值为1.7%。石英流体包裹体的δ18OSMOW值在14.6×10-3~15.5×10-3之间,δDSMOW值在-84.1×10-3~-73.8×10-3之间,δ18OH2O值在2.7×10-3~3.6×10-3之间。综合以上表明:成矿流体以大气降水为主,混有岩浆热液。