Microchemical Characterization of Natural Gold and Copper Alloys from the Ancient Um Shashoba Gold Mine,South Egypt     

Mohamed Abdallah Gad DARWISH 《《地质学报》英文版》2014,88(1):196-212

The SEM-EDX technique was applied to investigate Au, and Cu＋Sn alloyed grains in the mineralization of the Um Shashoba mine for achieving further understanding of occurrences, internal structures and microchemistry of Au and Cu alloys and associated minerals, and mineralization type. This study is aiming at the genetic history of ore-bearing fluid events, geochemical evaluation and exploration significance. The results showed that the mineralization could be considered as a single major episode generated by metamorphic mesothermal solution rich in sulfides and unsaturated respect to Au. It was differentiated into many stages; started with formation of auriferous pyrite that was pseudomorphed by secondary hematite, limonite and goethite. Three phases of Au alloy were precipitated, and Cu＋Sn and Ag-rich alloys were produced respectively and followed by deposition of two generations of barren pyrite. Calcite and ankerite were crystalized, surrounded and partially replaced some of early formed minerals. Finally, barren muscovite recrystallized around and inside both later formed carbonate minerals that were free of any sign of Au in their structures. The processes of deformation, recrystallization, annealing, dissolution, remobilization and re-precipitation played the most important roles in the genetic history of the mineralization.  相似文献   

瞬变电磁法在福建某铅锌矿井下勘查中的应用          下载免费PDF全文

钟华  钟乳石  刘和花  陈振宁  刘沈衡 《地质找矿论丛》2014,29(1):120-124

老矿山深部、外围找矿是当前"以矿找矿"为重要方式。文章以福建某铅锌矿为例,通过坑道内开展小线框、大电流的瞬变电磁法获取电阻率异常,利用坑内钻进行验证,取得了良好的找矿效果,为老矿山勘探提供了新的有效的物探方法。  相似文献   

城镇周边土壤中含铅矿物的环境意义   总被引：1，自引：0，他引：1  

汤丽玲  马生明  王之峰 《物探化探计算技术》2014,(6):736-741

通过对长江下游南京至苏州一带铅污染土壤中含铅矿物的鉴定识别和来源分析,确定土壤中铅的来源,既有附近含铅矿床开采过程中带出的含铅矿物,也有人为叠加的成分。作为相对稳定的含铅矿物,方铅矿、白铅矿和人工含铅颗粒含量越高,土壤中有效态铅所占比例就越低。对Pb异常土壤中含Pb矿物的研究,可以解释土壤与农作物籽实中铅含量间的复杂关系,同时也可以为生态地球化学评价标准和预测预警方案的制定提供参考。  相似文献   

吉林省辉南县腰岭子金矿地质特征及浅部资源储量预测     

李永宽  刘祥超  刘萍 《吉林地质》2014,(4)

阐述了腰岭子金矿成矿区域地质背景、地质特征和矿区地质特征与成矿条件。总结了地质、物探、化探综合找矿成果。确定了金矿体主要赋存于韧性剪切带的硅化、黄铁矿化糜棱岩化斜长片麻岩中,由含金石英脉构成。同时对浅部资源储量进行了预测,估算出金矿体的远景资源/储量共计3.84 t。上述总结对本区找矿具有重要指导意义。  相似文献   

矿山开发中的含水层破坏评估方法初探——以白山市恒基煤矿为例     

林琳  王屹林  谢冬月  李良顺  王鹏  李东川 《吉林地质》2014,(4)

本文以白山市恒基煤矿为例,在阐述矿区地质环境基础上,探讨了矿山开采中的含水层结构破坏评估方法,含水层水位、水量变化、和采矿活动对含水层水质造成的污染。最后提出了防治措施,为矿山地质环境恢复治理提供科学依据,也为其他矿山开采提供参考。  相似文献   

贵州晴隆-安龙露采金矿矿山地质环境质量评价体系探讨与应用     

刘发祥  ;唐升贵  ;伍锡举 《矿产与地质》2014,(4):511-517

据贵州省晴隆―安龙金矿矿山地质环境背景、现状、矿山环境地质问题、人类工程活动强度与地质环境质量的相关性,并结合金矿露采的特点,探索性地提出了一套金矿露采矿山地质环境质量评价的方法体系并用之于调查区的地质环境质量分区评价,通过专家进行野外验收和成果报告审查,一致认为评价结果比较真实地反映了调查区的实际地质环境质量状况,提出的评价方法是合理可行的,对类似金矿矿山的地质环境质量评价具有一定的借鉴意义。  相似文献   

西藏自治区昂仁县朱诺铜矿地质特征及找矿潜力远景评价   总被引：1，自引：0，他引：1  

张武昌 《陕西地质》2014,(1):22-26

通过典型斑岩型铜矿模式对比,朱诺铜矿含矿斑岩体剥蚀程度为钾化带和黄铁绢英岩化上部,向深部及西部,具有较大的找矿潜力。  相似文献   

陕北榆横矿区小纪汗井田水文地质特征及矿床充水条件分析     

李玮娜  高春华  张天天  张旭梅 《陕西地质》2014,(2):84-90

从用顶板充水、底板突水两个角度对矿坑充水强度进行了分析,为小纪汗井田及周边开采提供了参考。  相似文献   

陆生植物氮同位素组成与气候环境变化研究进展   总被引：3，自引：0，他引：3  

刘贤赵  张勇  宿庆  田艳林  王庆  全斌 《地球科学进展》2014,29(2):216-226

近年来,由于植物氮同位素组成(δ15N)记载了气候环境变化的信息,因而被广泛应用于全球变化研究中,成为古气候环境再造和了解现代气候环境变化信息的有力工具。然而,人们对气候环境引起的δ15N变化及其指示的气候环境意义并不完全清楚,这就有可能限制植物δ15N在古气候环境变化等领域研究中的应用。在概述植物氮同位素分馏和植物不同氮源的氮同位素分布的基础上,分析了温度、降水、大气CO2浓度和海拔高度等气候环境因子对陆生植物δ15N的影响以及它们的关系。指出了目前研究中存在的问题及其研究前景,认为在全球变化研究中利用植物氮同位素技术不仅可以重建古气候环境(如重建大气CO2浓度变化),揭示历史时期温度、降水的变化,而且还可以在一定的时间和空间上综合反映生态系统氮循环的特征。  相似文献   

Research Progress in Responses of Modern Terrestrial Plant Carbon Isotope Composition to Climate Change   总被引：1，自引：0，他引：1  

Liu Xianzhao  Zhang Yong  Su Qing  Tian Yanlin  Quan Bin  Wang Guoan 《地球科学进展》2014,29(12):1341-1354

Global climate change has been one of the most concerned environmental problems in the world since the 1980s. Since stable carbon composition (¹³C) in plant tissues can record abundant information on climate changes, it has been widely used as an important climate proxy in global change studies and becomes a powerful tool for obtaining paleoclimate information, understanding paleoenvironment reconstruction and modern climate change, and predicting future climate trends. However, a lot of potential uncertainties have always involved in the reconstruction of paleoclimate and paleoenvironment by carbon isotope of the past period sediment or fossils. Among them, the most dominant uncertainty is due to our poor understanding of the relations between carbon isotope ratios of plants and climatic factors and the climatic and environmental significance indicated by modern plant ¹³C. This may limit the application of plant ¹³C in the study of climatic and environmental changes. Based on the Summary of plant ¹³C fractionation and carbon isotope distribution of different photosynthetic plants, the effects of environmental factors, e.g., temperature, precipitation, atmospheric CO₂ concentration, and altitude on terrestrial plant ¹³C and their relationships were reviewed in this paper, and the response mechanism of plant ¹³C to climate changes were also analyzed. Furthermore, the current existing problems and the future prospects in carbon isotope study were discussed. It is pointed out that strengthening some studies such as the response of C₄ plants ¹³C to climate environmental parameters, the transformation relation of different scale plant ¹³C, intersection and permeation of related disciplines, and various proxies and scientific method, will undoubtedly make us have a more accurate understanding of the climate history and eventually broaden the development of the field during the process of global change study by plant carbon isotope techniques.  相似文献