共查询到20条相似文献，搜索用时 93 毫秒
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张凤鸣 《水文地质工程地质》1980,(3)
简易水文地质工作是了解勘探区水文地质条件的基础工作,在各勘探阶段都很重要。 普查阶段一般不进行专门水文地质工作,简易水文地质工作就成为了解水文地质条件相当重要的手段,有时甚至是唯一的手段。所得资料是专门水文地质工作的依据。专门水文地质工作量毕竟是有限的,要对水文地质条件作全面评价还要辅之以大量的简易水文地质工作。 相似文献
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财神庙矿区在水文地质勘探评价中,总结初勘中水文地质规律,指导水文地质勘查工程;利用非探矿工程进行抽水放水试验;利用构造孔、找矿孔开展水文地质观测;实施水文地质与地质设计、钻探施工三结合的一套工作方法,实践证明,这些水文地质勘探方法是可行的,有效的,缩短了勘探工期,降低了工作成本,获得了良好地质效果和经济效益。 相似文献
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韩树青 《水文地质工程地质》1988,(5)
煤田水文地质勘探钻孔,即是取煤、岩芯孔又是水文地质孔;而且一个钻孔中最少作两层抽水试验。因此,分隔上下含水层是不可缺少的工作之一。根据水文地质条件,选择止水材料与止水方法是抽水试验的关键。为此在实际工作中改进止水方法和选择最佳止水材料是保证抽水试验成功的先决条件。多年施工中采用变径管靴止水,得到良好效果和可喜的经济效益。 相似文献
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冶金系统的矿区水文地质工作,在近一两年调整期间,通过对一些矿区水文地质补课,以及对水文条件复杂矿区的专门水文工作,使我们的技术水平和管理水平都有所提高,质量上也基本满足了矿山生产、设计要求.但在水文地质勘探设计中,仍有一些问题值得注意,现提出有关编审矿区水文地质勘探设计的几点意见,以供同志们参考.把好设计关,防止水文地质工作与总体脱节 相似文献
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广西煤炭工业局合山矿区水文地质探采对比小组 《煤田地质与勘探》1978,6(6):72-79
合山煤田开采前经过两次精查,先后进行了1比5万和1比1万的水文地质测绘、简易水文地质观测、专门孔组抽水试验、地下水动态长期观测、水文测井等工作,基本上查明了本区的主要水文地质问题。矿层开采后,又积累了新的资料。对本区水文地质条件及其工作方法有了进一步认识。 相似文献
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针对肥城国家庄煤矿"三面阻水、一面进水"的水文地质边界条件,合理选择帷幕截流带,利用井下巷道结合浆液扩散半径布置帷幕注浆钻孔,采用井上下结合的粘土水泥浆注浆工艺和群孔注浆、引流注浆、控压注浆等工艺,完成帷幕截流工程带1 700m,帷幕效果97.9%.本文详细叙述了帷幕注浆孔的施工参数和帷幕注浆工艺. 相似文献
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Robert M. Gailey 《Hydrogeology Journal》2017,25(7):2163-2183
Water supply wells can act as conduits for vertical flow and contaminant migration between water-bearing strata under common hydrogeologic and well construction conditions. While recognized by some for decades, there is little published data on the magnitude of flows and extent of resulting water quality impacts. Consequently, the issue may not be acknowledged widely enough and the need for better management persists. This is especially true for unconsolidated alluvial groundwater basins that are hydrologically stressed by agricultural activities. Theoretical and practical considerations indicate that significant water volumes can migrate vertically through wells. The flow is often downward, with shallow groundwater, usually poorer in quality, migrating through conduit wells to degrade deeper water quality. Field data from locations in California, USA, are presented in combination with modeling results to illustrate both the prevalence of conditions conducive to intraborehole flow and the resulting impacts to water quality. Suggestions for management of planned wells include better enforcement of current regulations and more detailed consideration of hydrogeologic conditions during design and installation. A potentially greater management challenge is presented by the large number of existing wells. Monitoring for evidence of conduit flow and solute transport in areas of high well density is recommended to identify wells that pose greater risks to water quality. Conduit wells that are discovered may be addressed through approaches that include structural modification and changes in operations. 相似文献
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Saltwater intrusion in coastal regions of North America 总被引：7，自引：3，他引：4
Saltwater has intruded into many of the coastal aquifers of the United States, Mexico, and Canada, but the extent of saltwater intrusion varies widely among localities and hydrogeologic settings. In many instances, the area contaminated by saltwater is limited to small parts of an aquifer and to specific wells and has had little or no effect on overall groundwater supplies; in other instances, saltwater contamination is of regional extent and has resulted in the closure of many groundwater supply wells. The variability of hydrogeologic settings, three-dimensional distribution of saline water, and history of groundwater withdrawals and freshwater drainage has resulted in a variety of modes of saltwater intrusion into coastal aquifers. These include lateral intrusion from the ocean; upward intrusion from deeper, more saline zones of a groundwater system; and downward intrusion from coastal waters. Saltwater contamination also has occurred along open boreholes and within abandoned, improperly constructed, or corroded wells that provide pathways for vertical migration across interconnected aquifers. Communities within the coastal regions of North America are taking actions to manage and prevent saltwater intrusion to ensure a sustainable source of groundwater for the future. These actions can be grouped broadly into scientific monitoring and assessment, engineering techniques, and regulatory approaches. 相似文献
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针对新集二矿新生界松散层，推覆体下开采的特殊地质及水文地质条件，通过对夹片地层水文工程地质条件，边界条件及富水性特征的分析，阐明夹片地层在防水煤柱留设中的意义，并通过生产实践验证，取得了较好的经济及技术效益。 相似文献
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Characterization of regional land subsidence in Yangtze Delta, China: the example of Su-Xi-Chang area and the city of Shanghai 总被引：5，自引：1，他引：4
Xiaoqing Shi Yuqun Xue Jichun Wu Shujun Ye Yun Zhang Zixin Wei Jun Yu 《Hydrogeology Journal》2008,16(3):593-607
Su-Xi-Chang area and the city of Shanghai, located in the south of Yangtze Delta, China, has subsided due to groundwater overpumping. Because of the regional scale of the groundwater exploitation, cone of depression and land subsidence at present, Su-Xi-Chang area and Shanghai are treated as a single area for a land subsidence study, which could more clearly elaborate the relationships between the deformation features of hydrostratigraphic units and the different sites of the cone of depression. All hydrostratigraphic units in the study area were discussed throughout. Based on the field data, including data on compression of individual strata from groups of extensometers and groundwater levels from observation wells, the relationship between the deformation and the groundwater level was analyzed. The results indicate that the deformation features of the hydrogeologic units are greatly related to hydrogeologic properties and groundwater-level variations. An identical hydrogeologic unit may exhibit different deformation features in different locations such as along the periphery and in the center of the cone of depression. In addition, in the same location, a hydrogeologic unit also exhibits different features in different periods because of different groundwater level variations. The delay phenomenon of the sandy aquifer is not specific but occurs widely. 相似文献
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W. C. Sidle 《Environmental Geology》1993,21(1-2):42-50
About 19 percent of sampled residential water wells situated in a pristine, granitic Maine (USA) coastal environment have elevated mercury concentrations according to USEPA standards. There are no identified anthropogenic sources for mercury but some local granitoids have anomalous mercury concentrations in the Waldoboro Pluton Complex (WPC). Site-specific hydrogeologic conditions appear to have aggravated what is otherwise only trace amounts of some naturally occurring toxic analytes in the groundwater in contact with the suspect granitoids of the WPC. The extent of mercury in this crystalline rock environment is examined here. It is prudent to exercise preventive measures and appropriately site water supply wells and not expect complete remediation of the affected homeowners' wells. 相似文献
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Potentially contaminating activities such as mining and waste disposal, which require environmental hydrogeologic monitoring, may be located in or above fault zones. Two case studies of ground water monitoring at waste disposal sites in California illustrate the effect such fault zones may have on water tables. A fault gouge area in the Garlock fault zone has a potentiometric surface (a conceptual surface plotted using water elevations in monitoring wells and springs) which intersects the ground surface. The planar Kern Bluff fault produces a stepped water tabel. It is suggested that due to geologic and other environmental similarities, studies of environmental impacts of projects along the Ataca fault zone and Pocuro fault zone in Chile may encounter similar hydrogeologic phenomena. 相似文献
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Fatoumata Barry Duke Ophori Jeffrey Hoffman Robert Canace 《Environmental Geology》2009,56(8):1593-1603
Delineating capture zones of pumping wells is an important part of safe drinking water and well protection programs. Capture
zones or contributing areas of a groundwater extraction well are the parts of the aquifer recharge areas from which the wells
draw their water. Their extent and location depend on the hydrogeologic conditions such as groundwater recharge, pumping scenario
and the aquifer properties such as hydraulic conductivity, porosity, heterogeneity of the medium and hydraulic gradient. Different
methods of delineation can be used depending on the complexity of the hydrogeologic conditions. In this study, a 3-dimensional
transient numerical MODFLOW model was developed for the Central Passaic River Basin (CPRB), and used with a MODPATH particle
tracking code to determine 3-dimensional transient capture zones. Analytically calculated capture zones from previous studies
at the site were compared with the new numerically simulated capture zones. The study results revealed that the analytical
solution was more conservative, estimating larger capture zones than the numerical models. Of all the parameters that can
impact the size, shape and location of a capture zone, the hydraulic conductivity is one of the most critical. Capture zones
tend to be smaller in lower hydraulic conductivity areas. 相似文献