应用模糊集合论圈定找金靶区     

冯维恒  胡兴凤 《铀矿地质》1988,(2)

本文依据岩浆岩常量评价因子的系统分析和建立在模糊集合论基础上的矿化隶属度研究,得到了能识别包括金在内的10种多金属矿(Au、Cu、Mo、U、W、REE、Nb-Ta、Be和Sn)的母岩的方法。以江苏省岩浆岩为例,计算了有关岩体的金矿化隶属度,划分了4级找金靶区,对指导找矿起到了积极作用。作者用该法对一些著名产金矿岩浆岩的化学成分所作的研究表明,所设计的两类与金矿化隶属度有关的数学模型及其聚类中心是合理的、准确的。  相似文献   

灰色聚类在洪水灾害等级划分中的应用   总被引：4，自引：1，他引：3  

陈亚宁  杨思全 《干旱区地理》1999,22(3):37-42

基于灰色系统理论,阐述了灰色聚类分析的基本原理和步骤,并结合新疆“９６．７”特大暴雨洪水典型地州市灾害等级划分的实例,对其进行了应用分析。最后得出此次暴雨洪水灾害中典型地州市的聚类系数和灾度等级表,取得了良好效果。这表明灰色聚类分析是灾害等级划分问题的一条有效解决途径。  相似文献   

贵州省赤水市耕(园)地土壤质量地球化学评价          下载免费PDF全文

唐婷婷  牟军  田文明  唐佐其  强希润  王安华 《贵州地质》2020,37(3):244-250, 232

贵州西部中、上二叠统界线附近普遍发育与玄武岩风化壳有关的铁-多金属矿化。本文通过对贵州西部普安地区二叠系茅口组顶部古风化壳型铁矿详细野外地质调查发现,玄武岩风化壳剖面普遍发育铁矿化,但铁矿体主要呈透镜体产于喀斯特洼地或溶斗之中,剖面上表现为Fe由上而下运移富集的特征。7件岩（矿）石样品地球化学分析表明,贵州西部普安地区二叠系茅口组顶部玄武岩风化壳普遍富集Fe、Ti、Al的氧化物,As、Sb、Cu、Nb、V、U、Zr等亲硫及高场强元素。该区部分样品TFe2O3、TiO2含量达到工业品位,Al2O3也呈不同程度富集,具有铁-多金属富集的特征。此外,研究区Fe倾向于喀斯特洼地富集,而Ti、Al则倾向于残留喀斯特斜坡富集,具Al、Ti与Fe差异性分离的特征,这可能与玄武岩间歇性喷溢,古地理特征,风化作用及频繁海侵、海退事件关系密切。综合研究表明,峨眉山地幔柱活动推动了贵州西部古地理格局的演化（喀斯特不整合洼地）,并造就了（矿源层）高铁钛玄武岩堆积。贵州西部二叠系茅口组顶部古风化淋滤作用及古地理格局演化对Fe的迁移及富集具有显著的控制作用。因此,对于贵州西部二叠系茅口顶部玄武岩风化壳及其古地理恢复的研究是寻找玄武岩风化壳型铁矿床的重要基础。  相似文献   

Liberation-limited grade/recovery curves from X-ray micro CT analysis of feed material for the evaluation of separation efficiency     

Jan D. Miller  Chen-Luh Lin  Lukasz Hupka  Mohamed I. Al-Wakeel 《International Journal of Mineral Processing》2009,93(1):48-53

Procedures for 3D mineral liberation analysis by X-ray micro CT (XMT) are presented and discussed including the construction of liberation-limited grade/recovery curves for specific feed materials. In this way, actual separation efficiencies can be compared to what might be expected for a perfect separation limited only by the extent of liberation. It is shown that 3D mineral liberation analysis based on XMT is preferred to 2D section analysis which overestimates the extent of liberation. By way of example, procedures and experimental results are presented and discussed for feed material in the case of phosphate rock flotation.  相似文献   

近年我国矿产勘查重大成果特征与分析     

陕亮  张万益  姚晓峰  马腾  刘江涛  贾德龙  王尧  张鑫刚 《地质论评》2016,62(S1):154-156

2010~2014年,我国矿产资源重要勘查成果不断涌现。为开展矿产勘查进展长期动态跟踪与成果集成,进一步服务十三五全国矿产勘查规划部署,笔者依托原中国地质调查局发展研究中心承担的地质调查项目,以我国21个重点成矿区带和铁、铜、铝等14类重要矿种的勘查进展为研究对象,分析了勘查成果特征,开展了成果概况、分布区域、探获资源量、加权平均品位等多方面综合评价。  相似文献   

土地定级估价信息系统开发研究   总被引：5，自引：1，他引：4  

董廷旭 《地球信息科学学报》2000,2(1):76-79

利用 GIS技术建立土地定级估价信息系统在目前大中城镇土地定级估价中显得尤为重要。本文结合绵阳市城镇土地定级评估 ,介绍了城镇土地定级估价信息系统的设计方法和实施流程。强调数据规范化、模块完备性与扩充性、功能实用性、操作可视化等设计原则 ,实现了城镇土地定级、基准地价评估、宗地评估和地价指数测算的数据采集、数据处理到数据管理与决策的自动化。  相似文献   

贵州施秉县耕地质量等级与保护利用建议          下载免费PDF全文

万将  邰安琪  陈孝举  杨杰 《贵州地质》2020,37(4):497-501

针对车间的混合流水线调度问题（HFSP）存在智能算法寻优过程中节能目标即适应值评估代价高的问题,首先,通过分析车间节能模型建模的编码方式,提出一种基于矩阵编码机制的特征向量提取方法,引入核函数有利于极限学习机（ELM）求解节能目标。其次,对需要构建代理模型的改进多目标多元宇宙优化算法（IMOMVO）进行计算复杂度分析,建立了基于ELM的代理模型,设计数据驱动优化的车间节能目标算法框架。最后,基于均匀分布变量的拉丁超立方抽样,形成初始化样本,与BP算法进行预测性能验证和计算时间对比两个实验。实验结果显示,ELM算法的拟合优度为0.97381,预测性能指标均优于BP算法。单个适应值平均计算时间为5.4×10-4 s,仅为真实求解的18.5%。说明ELM在车间节能目标预测问题具有良好的效果。  相似文献   

Equilibrium and time scales in geomorphology: Application to sand-bed alluvial streams     

Alan D. Howard 《地球表面变化过程与地形》1982,7(4):303-325

Equilibrium is defined as a single-valued, temporally invariant functional relationship between the values of an output variable and the values of the input variable(s) in a geomorphic system. Disequilibrium occurs if the output deviates from the functional relationship by more than a consensual degree. Natural geomorphic variables are characterized by a relaxation time. Output variables are insensitive to cyclical inputs with frequencies much greater than the relaxation time, but can respond completely for sufficiently low frequencies. Rapid trends, recent step changes or pulse inputs, and intermediate frequency inputs can cause disequilibrium. The gradient of sand-bed alluvial channels (the output variable) is determined by sediment and water delivery from slopes (the input variables), and changes in this hydraulic regime require regrading by erosion and deposition. Initial stages of adjustment to changed regime in a long, unbranched channel with sediment and water delivery only at the upstream end propagate downstream, but later stages of adjustment occur simultaneously throughout the reach. In a dendritic channel network the gradient responds rather uniformly throughout the network to changes in regime during all stages of adjustment. The time scale of adjustment to changed regime depends upon the size of the channel network (or stream length), the sediment and water discharges, and to a lesser degree upon the magnitude of the change. Grade as defined by Mackin (1948) is synonymous with equilibrium as used in this paper if ‘a period of years’ is replaced by ‘a time period commensurate with the relaxation time of the gradient’. The use of the term grade is best restricted to a single-valued relationship between channel gradient and the hydraulic regime.  相似文献   

Recent Developments in Marine Diamond Mining     

Richard H. T. Garnett 《Marine Georesources & Geotechnology》2002,20(2):137-159

The marine diamond deposits of southern Africa owe their existence to fluvial transport down the Orange River to the South Atlantic. On the coast, they were moved, sorted and concentrated by high-energy sea and wind conditions to create a veneer of diamondiferous gravels on the sea floor. Large scale, offshore production by De Beers Marine commenced in 1989 in Namibian waters. The company now acts as a contractor for Namdeb, a corporation owned jointly with the Namibian governments. Some junior public companies also produce diamonds by large-scale mechanized means and conduct extensive exploration programs. Two important developments have occurred recently. Firstly, equipment for the recovery of diamonds from the seabed has been successfully borrowed from other industries. Large drills from onshore civil engineering have been modified for marine sampling and mining. Remotely controlled, seabed-mounted, excavational systems have assumed a major role. The new systems allow both evaluation sampling and subsequent mining to be undertaken by similar or the same equipment, making the results compatible. They permit highly selective extraction and enhanced recovery of the gravels from irregular bedrock in water approaching 200 m deep. But none is universally applicable offshore, each being the preferred system under different conditions. Secondly, the total output of sea diamonds from Namibian waters has increased to 0.8 million carats annually and now exceeds that from all the country's onshore sources. An industry has become established. Corporate and individual perseverence, government encouragement, new technology, shareholders' risk finance, and De Beers' diamond marketing have all played a role in the success. Future diamond production may increase as companies meet the challenge of working lower grade, higher volume deposits, which will require new approaches to the mining process. With a decrease in the physical risk of marine mining, the most variable inputs in operational planning and production forecasting are recovered grade and throughout rate, together with equipment availability. The importance of reliable grade estimation from sufficient sampling density is widely perceived, but the greatest performance risk can involve the predicted excavation rate and 'mineability' of the seabed sediments. Published reserve statements would benefit from a requirement to specify the planned mining method, the consequent cutoff grade to be employed, and whether or not test mining has been undertaken.  相似文献   

史料考证与找矿(之四)：个旧锡矿   总被引：1，自引：0，他引：1  

薛步高 《云南地质》2002,21(4):447-455

著名的个旧锡矿，据史料在元廿七年（1290年），率先在老厂矿区银铜矿开始采银（铅）-锌矿。清康熙四十六年（1707年），始由官方主持大规模开发砂锡矿，直至民国初年（1910年）都以采-冶砂锡为主，元廿七年后，银硐，黄茅山，竹林山，龙树脚等老硐深部，相继发现并转入原生锡矿开采。个旧300余年的采-选-冶开发史，使当地矿工在识别砂锡，脉锡不同矿石类型（荒），涮碗目测品位，水力采矿（冲荒尖），水力洗选（溜口），土法炼锡，锡锭表面“花口”识别等诸多领域，创造出一套完整的采-选-冶工艺，在中国矿业史上作出重大贡献。  相似文献