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通过对潘谢矿区几起典型出水事故案例的分析,总结出工作面顶板砂岩出水具有出水时间短,水量迅速增大,储量以静储量为主等特点,分析了影响顶板砂岩涌水的主要因素(砂岩的发育厚度、埋藏深度、地质构造的影响、地下水对其补给的条件、煤层采动对覆岩的破坏程度、工作面的推进速度、钻孔的封闭质量等),并提出防治煤层顶板砂岩水害的综合措施. 相似文献
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Ramil Ahmadov Atilla Aydin Mohammad Karimi-Fard Louis J. Durlofsky 《Hydrogeology Journal》2007,15(7):1239-1250
The effect of open and filled slip surfaces on the upscaled permeability of two fault zones with 6 and 14 m strike-slip in an eolian Aztec Sandstone, Nevada, USA is evaluated. Each fault zone is composed of several fault components: a fault core, bounded by filled through-going slip surfaces referred to as slip bands, and a surrounding damage zone that contains joints and deformation bands. Slip band geometry, composition, and petrophysical properties are characterized. Measurements and modeling show that slip band permeabilities can vary over 12 orders of magnitude depending on the degree of fill within the slip bands. The slip bands along with other fault zone components are represented in finite volume numerical calculations and the impact of various slip-band representations on upscaled fault zone permeability is tested. The results show 2 orders of magnitude variation in upscaled fault zone permeability in the fault-normal direction and a factor of 2 variation in the fault-parallel direction. The numerical results presented here are compared to the earlier numerical results in which structured Cartesian grids were used for the numerical simulations, and are in qualitative agreement with earlier calculations but use about a factor of 250–400 fewer numerical cells. 相似文献
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文章简要地阐述了红格尔地区盆地的地质概况,对找矿目的层下白垩统巴彦花群进行了层序地层划分和沉积体系分析,从铀源、构造、砂体发育规模及地层结构、氧化作用、后生还原作用、水文地质和铀矿化等几个方面对红格尔地区砂岩型铀矿成矿前景进行了分析,提出了砂岩型铀矿成矿远景地段和进一步探索的地段。 相似文献
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Steven?F.?ThorntonEmail author John?H.?Tellam David?N.?Lerner 《Geotechnical and Geological Engineering》2005,23(6):811-829
Current risk-based methods for assessing the effects of landfill leachate migration on groundwater resources are conservative and generalised. Cost-effective and practical strategies are required which can robustly determine the potential for contaminant attenuation on a site-specific basis. In this paper laboratory column experiments and reactive transport modelling are evaluated as a combined approach for assessing the chem’ical impact of leachate migration in the Triassic Sandstone aquifer. The results are compared with field data for a landfill in the East Midlands. Columns of aquifer sandstone were flushed sequentially with groundwater, followed by acetogenic or methanogenic leachate to simulate chemical interactions occurring during leachate loading episodes. The key contaminants in leachate (NH4, heavy metals, organic fractions) were attenuated by ion exchange, redox reactions, sorption and degradation. These processes produce a consistent hydrochemical signature which may help identify the extent of leachate migration in the aquifer. The laboratory results largely replicate those found in the field system, and the behaviour of inorganic contaminants during leachate flushing of the aquifer columns can be described by the reactive transport model. The experimental and modelling approach presented represents a powerful tool for risk assessment and prediction of leachate contaminant fate at unlined and lined landfills. 相似文献
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洛带气田蓬莱镇组中上部天然气藏的储层主要为三角洲前缘的水下分流河道、河口砂坝、水下决口河道和远砂坝微相砂体.储集空间以粒间孔和粒内溶孔为主.储集岩的孔隙度一般为8%~16%,渗透率均值为1.970×10-3μm2,属低中孔隙度、低渗透率储层.储渗性主要受方解石、硬石膏、长石含量和粘土矿物的影响.沉积微相控制了储层砂体的类型和展布特征.根据区内储集岩的岩石学特征、物性参数和孔喉结构特征,将其划分为四种类型. 相似文献