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991.
区域构造、可溶性岩层和地下水动力条件是岩溶陷落柱形成的3个必备条件。选取刘桥二矿作为研究区,从现有数据中分类提取出区域构造、可溶性岩层和煤层顶底板强富水异常区3个因素,根据底板等高线生成煤层底板坡度图及研究区邻近区域内已探明陷落柱的特征,结合这3个因素,运用GIS叠置分析圈定出4个可能的陷落柱发育区,再经与实际生产情况资料对比,得出巷道揭露的Ⅱ617风巷陷落柱位于第Ⅱ区内。 相似文献
992.
This article discusses the existing problems associated with reclaimed land in the area of the Antaibao Opencast Coal Mine, which is located in the semi‐arid region of northwest China. The following eight indicators of the suitability of the reclaimed land were developed based on the theory of soil genesis and landscape ecology: the thickness of the effective soil layer, composition of the soil surface, vegetation index, types of covering vegetation, slope of the terrain, time of reclamation, area of the evaluation unit, and the shape index of the evaluation unit. The suitability evaluation indexes of the reclaimed land were determined using the 3S technology and fuzzy evaluation methods, which revealed that the suitability of the reclaimed land in the study area could be divided into six grades and two categories, land suitable for farming, and land suitable for trees or grass. The suitability evaluation indicators and evaluation methods developed to evaluate reclaimed land in this study will be beneficial to the large‐scale rapid monitoring and the effective management of reclaimed land in the opencast mine area. 相似文献
993.
计算机辅助矿产资源储量动态估算与管理模型 总被引:1,自引:0,他引:1
针对我国矿产资源储量监管水平落后,矿山资源储量动态估算、管理及图件编制信息化程度低的现状,以矿山日常勘探与开发工作流程为主线,以地矿点源数据库为基础,研究了一种新的可对不断勘探与开采的矿山提供有效支持的计算机辅助矿产资源储量动态估算与管理模型。该模型可实现复杂多金属矿山资源储量二维及三维空间一体化与可视化动态估算,创新性地解决了复杂多金属矿山勘探与开发所面临的资源储量动态核减与管理问题。以基于该模型实现的矿产资源勘查与开发软件--QuantyMine传统方法矿产资源储量动态估算子系统为工具,以福建紫金矿业集团所属的多个矿山为实际应用对象进行模型检验。经与核实报告对比分析,所选取的某典型多金属矿床矿石量、金属量动态估算结果与报告结果相差分别为-1.78%~2.86%和-5.05%~4.45%,资源储量各类别结果接近。 相似文献
994.
山西大同小峪煤矿煤系粘土岩夹矸地球化学特征 总被引:1,自引:0,他引:1
采用化学法和中子活化(INAA)法,对山西大同小峪煤矿山西组和太原组的3件不同粘土岩样品的8种常量元素(氧化物)和33种微量元素含量进行了测定。通过对具有示踪意义的元素及其比值的对比分析表明,3个样品总体上均不具有典型的沉积岩特征,应该是由酸性或酸性偏碱性火山物质(降落的或陆源搬运的)在地表覆水较浅的弱氧化条件下经原地淋滤、蚀变形成的。岩石总体蚀变程度较高,不稳定或较不稳定的元素大量流失,甚至一些较稳定的元素(如高岭岩中的铁、锰)也明显流失。蚀变环境及介质条件、成岩原始物质组成及其粒度大小以及粘土物质组成是造成粘土岩类型及其不同类型间元素含量差异的主要原因。 相似文献
995.
T. Nasrabadi G. R. Nabi Bidhendi A. R. Karbassi H. Hoveidi I. Nasrabadi H. Pezeshk F. Rashidinejad 《Environmental Geology》2009,58(4):693-700
Sungun mine is the largest open-cast copper mine in northwest of Iran and is in the primary stages of extraction. The influence
of mining activity on the quality of regional groundwater has been taken in to consideration in this study. Accordingly, sampling
was done from 22 springs in the study area. The concentrations of major anions and cations as well as Al, Cu, Cd, Cr, Fe,
Mn, and Zn were determined for all 22 spring samples in mid-August 2005. The results showed that the concentrations of most
of these elements were below the USA Environmental Protection Agency (EPA) limits; however, Al and Fe concentrations are considered
to be more than limits in a couple of samples. Despite the fact that geological formations are highly weathered and fractured,
the dissolution of minerals within the study area is low. This may be justified by the relatively high alkalinity of local
underground water which keeps metals in solid phase and does not let them enter dissolved phase. Additionally, this may be
attributed to the high velocity of groundwater flows, which do not give enough time for minerals to dissolve. Correlation
coefficients among water chemistry components were determined and the weighted-pair group method was chosen for cluster analysis.
Accordingly, high correlation among Al, Fe and Cr, Cd ,and Cu, sodium absorption ratio (SAR) and Na as well as total hardness
(TH), Ca, and Mg were observed. The chemical characteristics of water compositions on the basis of major ion concentrations
were evaluated on a Schoeller and Piper diagram. Accordingly, the dominant type of water in the region is considered to be
Ca-HCO3 (calcium-bicarbonate type). However, this type of water is also rich in Na, K, and especially Mg. Regarding Schoeller diagram,
the current status of local underground water is good for drinking purposes. By commencing mining excavation with designed
capacity in near future, the minerals will come into contact with air and water resulting in dissolution, especially in ponds,
which, in turn, will increase the concentration of toxic metals in groundwater. Considering future uses of this water including
for drinking, irrigation, industrial purposes, etc., precautions must be taken in to consideration. 相似文献
996.
Impact of AMD on water quality in critical watershed in the Hudson River drainage basin: Phillips Mine,Hudson Highlands,New York 总被引:1,自引:0,他引:1
Sivajini Gilchrist Alexander Gates Zoltan Szabo Paul J. Lamothe 《Environmental Geology》2009,57(2):397-409
A sulfur and trace element enriched U–Th-laced tailings pile at the abandoned Phillips Mine in Garrison, New York, releases
acid mine drainage (AMD, generally pH < 3, minimum pH 1.78) into the first-order Copper Mine Brook (CMB) that drains into
the Hudson River. The pyrrhotite-rich Phillips Mine is located in the Highlands region, a critical water source for the New
York metro area. A conceptual model for derivation/dissolution, sequestration, transport and dilution of contaminants is proposed.
The acidic water interacts with the tailings, leaching and dissolving the trace metals. AMD evaporation during dry periods
concentrates solid phase trace metals and sulfate, forming melanterite (FeSO4·7H2O) on sulfide-rich tailings surfaces. Wet periods dissolve these concentrates/precipitates, releasing stored acidity and trace
metals into the CMB. Sediments along CMB are enriched in iron hydroxides which act as sinks for metals, indicating progressive
sequestration that correlates with dilution and sharp rise in pH when mine water mixes with tributaries. Seasonal variations
in metal concentrations were partly attributable to dissolution of the efflorescent salts with their sorbed metals and additional
metals from surging acidic seepage induced by precipitation. 相似文献
997.
矿井瓦斯评价与预测的构造动力学方法 总被引:1,自引:0,他引:1
通过对矿井瓦斯赋存的构造控制、构造应力场演化及构造煤结构演化与瓦斯特性耦合机理的综合分析,认为当前在矿井瓦斯赋存、分布规律及突出危险区带的有效预测方面的研究还有待深入。在汲取前人研究成果的基础上,提出矿井瓦斯突出的构造动力学评价与预测的思路及方法,即以区域构造-矿井构造-煤层变形-构造煤结构-瓦斯特性及其相互作用机理分析为总体思路.将现代构造地质学理论和方法引入矿井构造研究,并与模糊综合评判、灰色系统、分形理论、数值模拟和计算机技术相结合,以揭示构造煤发育、分布规律及其构造动力学控制机理,系统进行不同类型构造煤瓦斯特性研究,探讨不同结构构造煤的含气性、透气性和气体赋存状态,以构造煤分布特征作为瓦斯突出危险性评价与预测的基础,建立矿井瓦斯突出预测预报的构造动力学评价方法体系。 相似文献
998.
中关铁矿深孔注浆幕墙井间电阻率测试技术和效果评价 总被引:1,自引:0,他引:1
矿山治水中所采用的帷幕注浆工法具有典型的隐蔽工程特点,因此,注浆效果的评价一直是该领域内的一个难题.中关铁矿深孔帷幕注浆工程利用井间电阻率测试技术对注浆效果进行了深入的研究,验证了该物探手段在帷幕注浆工程中应用的可行性和先进性.井间电阻率反演图清楚地表明:注浆前后地层电阻率由低到高的变化过程,说明止水达到了良好的效果;本文还结合注浆工程资料,系统地分析了注浆过程中钻孔单位注灰量及岩层透水率的变化过程,为井间电阻率测试技术的试验结果和帷幕墙止水效果的检验评价提供了旁证支持. 相似文献
999.
1000.