准噶尔盆地顶山地区乌伦古河组氧化带元素地球化学特征及其与铀矿化的关系

主要对准噶尔盆地顶山地区乌伦古河组潜水氧化带和层间氧化带的砂岩进行主量元素、微量元素、稀土元素地球化学特征分析和对比.主微量元素特征显示：潜水氧化带的黏土作用,碳酸盐化作用,U、V、Mo的相关性比层间氧化带强.稀土元素特征显示：层间氧化带与潜水氧化带具统一的物源、沉积环境和构造背景,潜水氧化带轻重稀土分异程度、后生蚀变作用较层间氧化带强,层间氧化带Eu负异常较潜水氧化带明显.     

重铬酸钾氧化-硫酸亚铁滴定法快速测定海洋沉积物中有机碳

采用重铬酸钾氧化-硫酸亚铁滴定法，建立了一套快速测定海洋沉积物中有机碳含量的方法。选择了海洋沉积物样品的粒径大小、干燥温度和干燥时间，探讨了催化剂的用量及氯离子的干扰和消除方法。方法是对国标GB／T17378．5—1998的合理改进，大大地缩短了实验流程，降低了测定成本。对国家标准物质进行测定，并与仪器分析结果比对，证明本法可靠准确。     

Water management for acid mine drainage control at the polymetallic Zn–Pb–(Ag–Bi–Cu) deposit Cerro de Pasco, Peru

The geochemical and mineralogical study of the Quiulacocha tailings impoundment has shown that the hydrological connection of the three studied mine-waste systems at Cerro de Pasco (Pyrite-rich waste-rock dump Excelsior, old tailings impoundment Quiulacocha, and the active tailings impoundment Ocroyoc) is a critical concern for effective acid mine drainage (AMD) control and mine-waste management. The Quiulacocha tailings covered 114 ha, comprising 79 Mt of tailings, which contained  50 wt.% pyrite, and are located at 4340 m altitude in a tropical puna climate with about 1025 mm/a rainfall and 988 mm/a of evaporation. The tailings were partially overlain by the Excelsior waste-rock dump, which contains about 26,400,000 m³ of waste rocks that cover 94 ha and contained  60 wt.% of pyrite, which origin from a massive pyrite-quartz replacement body. Therefore, these two mine-waste deposits had a direct hydrological connection, resulting in the export of AMD produced at Excelsior towards Quiulacocha. In the Quiulacocha impoundment there are two different types of tailings recognized, that interact with the AMD from Excelsior: 1) Zn–Pb-rich tailings and 2) Cu–As-rich tailings. During the sampling, the Zn–Pb-rich part of Quiulacocha was not producing important excesses of AMD from the oxidation zone, since the pH increased to near neutral values at 1 m depth. The underlying tailings were still able to neutralize the acidity produced in the oxidation zone through sulfide oxidation by the carbonates (mainly dolomite and siderite) contained in the Zn–Pb mineral assemblage. The main source of AMD in this mine-waste system is the Excelsior waste-rock dump. Its acid seepage infiltrates into Quiulacocha forming a Fe–Zn–Pb plume with a pH 5.5–6.1 and containing up to 7440 mg/L Fe, 627 mg/L Zn, and 1.22 mg/L Pb. The plume was detected at 10–13 m depth in the stratigraphy of Quiulacocha tailings. Additionally, the AMD seepage outcropping at the base of the Excelsior waste-rock dump was channeled on the tailings surface into the Quiulacocha pond (pH 2.3), which covered the Cu–As-rich tailings. Infiltration of this Fe(III)-rich AMD increased tailings oxidation in the southwestern part of the impoundment, and subsequently liberated arsenic by enargite oxidation. Additionally, the AMD collected in the Quiulacocha pond was pumped into the active Ocroyoc tailings impoundment, where sulfide oxidation was strongly enhanced by the input of dissolved Fe(III). Therefore, the AMD management and a hydrological separation of the different mine-waste systems could be a first step to prevent further extension of the AMD problem in order to prevent increased sulfide oxidation by Fe(III)-rich solutions.     

层间氧化带砂岩型铀矿中铼的地球化学行为及找矿意义探讨

铼是地壳中一种极度分散的元素。在层间氧化带边界上 ,铼与铀的沉淀条件近似 ,在铼富集的层间氧化带砂岩型铀矿床中 ,铼富集的范围几乎与铀矿卷重叠。本文根据自然界已查证的层间氧化带砂岩型铀矿中铼、铀同消长的基本事实 ,对现阶段铼在层间氧化带砂岩型铀矿勘查中的找矿意义提出质疑。     

新疆布雅盆地铀成矿条件分析

布雅盆地是塔里木盆地南缘有利的铀成矿地段。在简析布雅盆地区域地质背景、已知铀矿化特征的基础上,着重宏观地分析了盆地形成铀矿化的地层、构造、水文地质及铀源等条件,以构造为主线初步总结出该区铀成矿的载体形成、初始铀富集、相对停滞和破坏及叠加富集4个阶段,独特的构造演化促成了铀矿化的形成。     

锰钾矿处理高浓度含酚废水研究

对人工合成锰钾矿氧化降解高浓度含酚废水的特性进行了研究。结果表明,体系酸度和矿物用量是影响废水处理效果的重要因素。加酸量为0.12 mol/L,矿物用量20 g/L,温度70℃,反应时间3 h时效果最佳,废水总酚含量由1269 mg/L降低至268 mg/L,同时CODCr与TOC去除率为31.2%和70.5%。经GC/MS测定,水中酚类物质为苯酚、甲基苯酚、二甲基苯酚,最佳条件下,酚类物质浓度已低至检测限以下,水中残余吲哚、长链烷烃、喹啉及其衍生物等难降解有机物。     

吐哈盆地层间氧化带砂岩型铀矿成矿条件分析及远景预测

本文运用水成铀矿的地质预测和评价标准,对控制吐哈盆地中下侏罗统层间氧化带砂岩型铀矿形成的构造背景、岩性岩相、水文地质特征、古气候、铀源等基本条件及层间氧化带发育特征进行分析,在此基础上预测了铀成矿远景,认为苏巴什－底哈尔、三道岭以及布尔加凸起西南部是层间氧化带砂岩型铀成矿远景地段,今后有必要做进一步的工作。     

含铁矿物的表面催化氧化作用及其环境意义

了解含铁矿物在环境地球化学和生物地球化学中所起的作用，重点在于介了解含铁矿物表面催化氧化作用对重金属As(Ⅴ)，Cr(Ⅵ)，U(Ⅵ)离子的表面还原反应，以及对有机污染物卤代烷烃、苯、氯苯、硝基苯类等芳香化合物的降解及退氯化作用，进而了解表面催化氧化作用的机制。     

Microbial Mats in the Mesoproterozoic Carbonates of the North China Platform and Their Potential for Hydrocarbon Generation

The well-preserved Mesoproterozoic succession in the North China platform consists mainly of three llthological associations including peritidal quartz sandstone, shallow marine and lagoonai dark to black shales, and shallow epeiric carbonates, with a total thickness of up to 8 000 m. In addition to well-documented microplants, macroalgae, and microbial buildups, abundant microbially induced sedimentary structures (MISS) and mat-related sediments have been recognized in these rocks. Intensive microbial mat layers and MISS are especially well preserved in the carbonates of the upper Gaoyuzhuang (高于庄) (ca. 1.5 Ga) and lower Wumishan (雾迷山) (ca. 1.45 Ga) formations, Indicating diversified microbial activities and a high organic production. In these petrified blomats, putative microbial fossils (both coccoidal and filamentous) and framboidal pyrites have been identified. The abundance of authigenic carbonate minerals in the host rocks, such as, acicular aragnnites, rosette barites, radial siderites, ankerites, and botryoidai carbonate cements, suggests authigenlc carbonate precipitation from anaerobic oxidation of methane (AOM) under anoxic/euxinic conditions. Warm climate and anoxic/euxinic conditions in the Mesoproterozoic oceans may have facilitated high microbial productivity and organic burial in sediments. Although authigenic carbonate cements may record carbonate precipitation from anaerobic methane oxidation, gas blister (or dome) structures may indicate gas release from active methanogenesls during shallow burial Bituminous fragments in mat-related carbonates also provide evidence for hydrocarbon generation. Under proper conditions, the Mesoproterozoic mat-rich carbonates will have the potential for hydrocarbon generation and serve as source rocks. On the basis of petrified biomats, a rough estimation suggests that the Mesoproterozoic carbonates of the North China platform might have a hydrocarbon production potential in theorder of 10×108t.     

New index of ferromanganese crusts reflecting oceanic environmental oxidation

Ferromanganese crusts (hereinafter crusts) form in aerobic environment and the environmental oxida-tion degree is recorded by the redox sensitive element Co in the crusts. The ages of the layers from the surface to bottom of the crusts are determined, and main element contents at high resolution along the depth sections of three crusts from the Pacific Ocean are analyzed by an electron microprobe. Thus the variations of Co/(Fe Mn) and Co/(Ni Cu) with age/depth of the crust layers are obtained. By comparing the ratios of Co/(Fe Mn) and Co/(Ni Cu) with the δ 18O curves of the Pacific benthic foraminifera, we find that these two ratios can reflect the variation of the environmental oxidation state under which the crust layers deposit. The evolution of the oxidation degree reflected by the two indexes resembles the evo-lution of temperature since the Oligocene reflected by the δ 18O curves of the Pacific benthic foraminif-era. This suggests that the crust-forming environment after the Oligocene is controlled mainly by the oxygen-rich bottom water originated from the Antarctic bottom water (AABW). However it is not the case prior to the Oligocene. Furthermore it suggests that the environmental oxidation degree controls the formation of the crusts and the Co contents in the crusts. This explains why the Co contents in the crusts increase with time up to now.