基于可视性分析与能量补偿的金属矿弹性波全波形反演

采用弹性波全波形反演方法精确重建深部金属矿多参数模型,建模过程采用基于地震照明的反演策略.首先给出基于照明理论的观测系统可视性定义,利用可视性分析构建新的目标函数,对反演目标可视性较高的炮检对接收到的地震记录在波场匹配时占有更高的权重,确保了参与反演计算中的地震数据的有效性;其次将给定观测系统对地下介质的弹性波场照明强度作为优化因子,根据地震波在波阻抗界面处的能量分配特点,自适应补偿波场能量分布和优化速度梯度,以提高弹性波全波形反演过程的稳定性和反演结果的精度.理论模型和金属矿模型反演试验结果表明,基于可视性分析和能量补偿的反演策略可以使弹性波全波形反演更快地收敛到目标函数的全局极小值,获得适用于金属矿高分辨率地震偏移成像的多参数模型.     

对澳大利亚金属矿产研究、勘探开发现状和特色的讨论与思考

在概述我国金属矿产资源研究、勘探开发所面临新的形势、任务和挑战的基础上,介绍了澳大利亚从事金属矿产研究、勘探开发的主要机构,介绍了澳大利亚与金属矿产资源研究、勘探开发有关的重大研究计划、研究中心、找矿新技术方法,总结了澳大利亚金属矿产资源研究、勘探开发的现状、特色以及对我国矿产资源工作的启示意义。     

秦岭造山带及邻区中生代地质演化与成矿作用响应

华(山-)熊(耳山)地块、南秦岭与川西金、铅锌-汞锑、钼-钨等矿床聚集区是秦岭成矿带乃至我国中央造山-成矿带的重要组成部分,无论华熊地块金、钼成矿,还是南秦岭及川西金、铅锌和汞锑矿床,它们的成矿地质背景、容矿与含矿建造、矿床类型、矿床规模及时空分布规律,均与中生代板块构造活动体系具密切的耦合关系.具体分析了大陆俯冲-碰撞和陆内造山构造-岩浆活动过程中,成矿构造地质背景、成矿盆地环境、沉积建造、成矿作用与矿床分布规律对大陆造山作用的耦合与响应.     

Lightning-induced magnetic fields in a building with large metallic plates

This paper evaluated lightning-induced magnetic fields in a building with large metallic plates using an equivalent circuit method. In the evaluation the metallic structure of a building during a lightning stroke was represented by an equivalent electrical network. Electrical network equations were built to find the current distribution in the structural elements, and subsequently the lightning-induced magnetic fields around the building. Special techniques were presented in the paper to model the large metallic plates and to derive equivalent circuit equations and circuit parameters. The coupling of metallic plates to building structural elements was also addressed. The proposed method was validated experimentally on a scaled structure model in the laboratory. Finally, lightning-induced magnetic fields in a laboratory building were characterized. It was found that the metallic plates changed the current distribution significantly within the metallic structure, and subsequently the lightning-induced magnetic fields in the building.     

金属矿物颜色指数在定性观察中的应用

金属矿物颜色指数是近代矿相学中定量测定的新进展。本文阐述了颜色指数的视觉反射率、色调、饱和度、色度坐标在定性观察方面的应用。视觉反射率比白光或绿光下测定的反射率更接近人目本身感觉的反射率。色度坐标可用于计算反射多色性的相对色度差以衡量反射多色性的显著程度。颜色指数用于编排金属矿物鉴定表,使鉴定表系统化、数字化且简明实用。颜色指数在金属矿物的鉴定工作方面具有指导作用。     

金属成矿40Ar/39Ar年代学的进展与问题——以黄铁矿、闪锌矿为例

长期以来, 由于金属成矿的多期性及易受后期蚀变的干扰, 成矿时代的确定成为难题, 进而成为成矿机理、矿床勘探等研究的制约因素。本文以黄铁矿和闪锌矿这两种典型的矿石矿物为例, 回顾了利用⁴⁰ Ar/³⁹ Ar法直接确定成矿时代的研究现状, 探讨了其中的问题、可能的解决方法及以后的发展前景, 为进一步开展矿石矿物的⁴⁰ Ar/³⁹ Ar年代学提供参考。同时对采自辽宁丹东青城子矿中的黄铁矿和闪锌矿样品做了包裹体镜下观察和电子探针的元素分析, 以期更好地理解矿石矿物⁴⁰ Ar/³⁹ Ar法直接定年的潜力。     

Mechanical responses of metallic strip flexible pipes subjected to pure torsion

Metallic strip flexible pipes (MSFP), a relatively new style of unbonded flexible pipes, are considered as an attractive alternative to traditional submarine pipes. Pipelines will inevitably confront torsion load which may affect the integrity and safety during their installation and application. Throughout this paper, the mechanical behavior of MSFP subjected to pure torsion is investigated by both experimental and numerical methods. Results from these two methods are essentially in agreement with each other. The finite element method (FEM) can be adopted to predict the failure torque of MSFP under torsion and analyze the detailed stress conditions of each layer. In addition, the effects of boundary conditions, layout manners of steel strips, friction coefficients between contact surfaces, twist directions and tension loads are discussed. The obtained conclusions will benefit cross-section design of MSFP and relative practical engineering.     

云南主要金属矿产开发史研究

云南金沙江砂金开发最早,始于战国时代;铜的开发居第二位,如东川、澄江始于西汉。至东汉大举开发矿产,如永平岩金,个旧、陆良的银（铅）;晋宁、保山的铁矿等。锌为人们认识与开发较晚的矿种,始于明代（华宁水角山）。史料中的１０处金产地,６处银（铅）与６处铅锌产地,３处铜产地均具有较好的地质背景,应实地调查。曾进行过评价的马关戛达厂铜矿,史料记载为银矿,确有银的伴生（１００×１００－６～２００×１０－６）,应重新评价。日本人编著的云南省志（矿产卷,１９４２）其中“大姚自家湾产锡”一节,系误传,应予纠正。     

铝分析中氟化物取代苦杏仁酸方法的改进

使用氟化物取代锌盐-EDTA滴定法,与电位滴定、光谱分析等手段在铝土矿、合金中铝含量测定,设备要求低,环境友好,分析方便易行,准确度和精密度上达到国家行业要求,有不可取代的优势。     

Variation of heavy metals in recent sediments from Piratininga Lagoon (Brazil): interpretation of geochemical data with the aid of multivariate analysis

In the last decade, the Atlantic coast of south-eastern Brazil has been affected by increasing deforestation and anthropogenic effluents. Sediments in the coastal lagoons have recorded the process of such environmental change. Thirty-seven sediment samples from three cores in Piratininga Lagoon, Rio de Janeiro, were analyzed for their major components and minor element concentrations in order to examine geochemical characteristics and the depositional environment and to investigate the variation of heavy metals of environmental concern. Two multivariate analysis methods, principal component analysis and cluster analysis, were performed on the analytical data set to help visualize the sample clusters and the element associations. On the whole, the sediment samples from each core are similar and the sample clusters corresponding to the three cores are clearly separated, as a result of the different conditions of sedimentation. Some changes in the depositional environment are recognized using the results of multivariate analysis. The enrichment of Pb, Cu, and Zn in the upper parts of cores is in agreement with increasing anthropogenic influx (pollution).