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991.
回顾了带压开采的传承与创新发展历程。阐述带压开采的概念及充要条件,以带压开采的内涵为基础,定义侵蚀基准面为浅部和深部带压开采的分界线(面),明确承压水上采煤为带压开采,而含水层“下”采煤不属于带压开采范畴,纠正《煤矿安全规程》中有关“顶、底板带压”的不妥表述。梳理了直接为带压开采服务的理论和技术,探(探查)、治(防治)、保(保障)3项技术,机理(致灾机理)、评价(危险性评价)、预测(灾变预测)3项理论,即构成带压开采理论技术体系;华北煤田奥陶系岩溶随深度增加发育减弱,由此推断,空间上深部岩溶径流带多形成在古岩溶系统中,而现代岩溶径流带则发育于现代岩溶中。深部隔水层损伤裂隙增多,为采后承压水导升奠定物质基础。总结对比了浅部和深部底板岩溶水害特征,阐明深部奥陶纪灰岩(简称奥灰)水突水机理,沿裂隙渗透、扩容、压裂,薄层灰岩中转,不断向上导升,形成大面积散流突水。从理论上说明突水系数已不适用隔水层厚度超出80 m的情形,提出厚、巨厚隔水层带压开采评价方法:p0 > 3σ3-σ1-pp+sT;依据隔水层厚度、底板破坏带、奥灰导升带、突水系数等因素将底板类型划分为5类隔水层,提出相应5级带压开采条件以及5种治理模式;针对深部带压开采复杂条件,倡导应用“全时空”水害综合防治思想理念及技术。面向未来,地质体+水流的本构模型仍是学术界需攻克的最大难题,现实的“卡脖子”难题,如深部岩溶发育规律、精细探查技术、水害机理及评价预测、综合治理技术等,是实现安全带压开采的关键。 相似文献
992.
澄合矿区位于渭北煤田中部,地质勘查时,发现从钻孔中较难采取到柱状或块状的煤心煤样,煤样疏松,多成为碎块状,甚至粉末状。基于地质构造、地层岩性和煤层特征的研究,认为该区煤心煤样破碎的主要原因一方面是由于在成煤过程中煤中的镜质组物质在煤化过程中受到温度、压力的影响,内生裂隙发育所致,另一方面是成煤后期地质构造的改造和破坏作用形成的,钻进时采用的钻压、转速、泵压和取煤器是次要因素。煤心煤样的破碎可从可磨性试验和邻近的煤矿井下采煤中得到佐证。建议以后在该区的勘查时采用单动双管取煤器。 相似文献
993.
洛河砂岩水是黄陵矿区供水水源中的唯一水质水量合乎要求的含水层。经过对洛河砂岩水水质的分析研究,发现洛河砂岩水水质分布有一定的规律性,具体表现为:溶解性固体、Na+含量、SO4^2-含量、Cl-含量在浅部较低,深部则有所增大;水质类型浅部为HCO3-Ca型,深部为HCO3-Na·Ca型;在动态变化上,呈现出随着开采时间的延续,溶解性固体、Na+、SO4^2-含量逐渐变小,Ca2+含量逐渐增大的趋势。强调在开发煤炭、石油时,一定要对洛河砂岩水加以保护。使其更好的为矿区建设服务。 相似文献
994.
M. J. Matias J. M. Marques P. Figueiredo M. J. Basto M. M. Abreu P. M. Carreira C. Ribeiro A. Flambó J. Feliciano E. M. Vicente 《Environmental Geology》2009,56(6):1227-1235
Santa Margarida Military Camp (S.M.M.C.) is the only one Portuguese military training area, including firing ranges for tactical
military manoeuvres of mechanised divisions. For this reason, various negative effects on the environment were expected due
to the military activities, as the Military Camp’s area is classified as a high vulnerability area to pollution of its multilayer
porous aquifers. The aim of this study was to identify and characterise local/regional geochemical impacts caused by the continuing
military training activities performed at S.M.M.C. in the course of 52 years. An overview of the geochemical research issues
as a basis for risk assessment is presented. A special attention has been put on the quality of local and regional surface
waters, shallow groundwaters and groundwaters. Local soils and sediments as well as fragments of shells and bullets were sampled
and analysed. The results so far obtained, indicated that none pollution effects were a consequence of the military training
activities. Till now, the geochemical signatures such as, high levels of K, Cl and NO3 in waters, detected in particular sites, should be faced as tracers of diffuse pollution ascribed to urban waste disposal
and cattle breading. 相似文献
995.
1992年以来,永夏矿区各矿井相继进行我高分辨地震勘探,本文就所取得的突出成果及验证情况作了全面的介绍,并分析了地震勘探成果的利用及效益。 相似文献
996.
Potential impacts of global warming on the frequency and magnitude of heavy precipitation 总被引:5,自引:0,他引:5
It is now widely recognised that the most significant impacts of global warming are likely to be experienced through changes in the frequency of extreme events, including flooding. This paper reviews physical and empirical arguments which suggest that global warming may result in a more intense hydrological cycle, with an associated increase in the frequency and/or magnitude of heavy precipitation. Results derived from enhanced-greenhouse experiments using global climate models (GCMs) are shown to be consistent with these physical and empirical arguments. Detailed analysis of output from three GCMs indicates the possibility of substantial increases in the frequency and magnitude of extreme daily precipitation, with amplification of the effect as the return period increases. Moreover, return period analyses for locations in Australia, Europe, India, China and the USA indicate that the results are global in scope. Subsequent discussion of the limitations of GCMs for this sort of analysis highlights the need for caution when interpreting the precipitation results presented here. However, the consistency between physically-based expectations, empirical observations, and GCM results is considered sufficient for the GCM results to be taken seriously, at least in a qualitative sense, especially considering that the alternative seems to be reliance by planners on the fundamentally flawed concept of a stationary climate. 相似文献
997.
创新勘查机制加快科学发展——泥河铁矿项目案例分析 总被引:1,自引:1,他引:1
安徽省庐江泥河铁矿勘查不仅取得了重大地质成果,更重要的是探索出一条公商衔接,多方联动,探采结合的勘查开发新模式。分析泥河铁矿项目从矿政管理到勘查开发的一系列举措,对实现找矿突破,加快资源开发,推动地勘单位改革发展具有重要的启示意义。 相似文献
998.
水体下的安全开采对于确保煤矿安全生产以及保护地表水、地下水资源等都具有十分重要的意义。本文以漳河水库库区下煤炭资源开采为例,通过对地质采矿条件、采场覆岩性质、覆岩破坏高度预计和开采条件进行分析,对库下采煤的安全性进行了研究和论证。结果表明:覆岩岩性和开采条件均有利于水库下开采,地表水和地下水之间的水力联系程度较低,导水裂缝带波及不到水库库底,因此,可以在水库下进行安全开采。最后,提出了相应的技术措施,以确保水库下安全采煤。 相似文献
999.
Summary This paper deals with the determination of subsidence parameters on a sloping ground surface above a completely mined underground panel in an inclined seam. A rays projection method is analytically developed to derive the subsidence components on the sloping ground surface from the corresponding ones on an assumed equivalent horizontal surface through the point of the mean elevation of the sloping surface above the extracted panel. Using the derived equations, the variation of subsidence with the inclination of the ground surface is analysed. An example is given to illustrate the application of the rays projection method in predicting subsidence effects on a sloping surface. 相似文献
1000.
Changes in the water properties and biological characteristics of the highly acidic Hromnice Lake (Western Bohemia) were investigated. This 110-year-old lake, formed as a consequence of the mining of pyritic shales, is permanently meromictic. Two chemoclines separate an extremely acidic (pH ~ 2.6) mixolimnion from a metal-rich anoxic monimolimnion. The absence of spring mixolimnetic turnover due to ice melting and very slow heat propagation through the chemocline with a 6-month delay were observed. Extreme mixolimnetic oxygen maxima (up to 31 mg l?1) in phosphorus-rich lake (PO43? up to 1.6 mg l?1) well correlated with outbursts of phytoplankton. Phytoplankton consist of several acido-tolerant species of the genera Coccomyxa, Lepocinclis, Chlamydomonas and Chromulina. Surface phytoplankton biomass expressed as chlorophyll-a varies from 2 to 140 μg l?1. Multicellular zooplankton are almost absent with the exception of Cephalodella acidophila, a small rotifer occurring in low numbers. Large red larvae of the midge Chironomus gr. plumosus were found at the bottom close to the shore, with larvulae in the open water. Developmental stages (protonemata) of a moss, resembling filamentous algae, dwell in the otherwise plant-free littoral zone. 相似文献