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61.
矿山开采活动中地下水与生态环境保护是需要综合利用多学科思想与理论解决的难题,仅从采矿工程学角度难以解决根本问题。文中从生态水文地质学的角度,针对陕北采煤安全必须疏排水和陕北能源基地建设亟须水资源支撑的现状,提出了通过充分地利用煤田地下水满足强劲用水需求来保护水资源的对策,并从矿区水文地质结构、地下水循环条件出发,根据矿区植被生态风险区划、采煤影响地下水区划,提出了建立保护矿山水资源的采煤秩序、不同阶段地下水保护与开发利用区划以及矿山掘进过程中保护性开采地下水的水源地布局规划原则与建设方案。 相似文献
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Groundwater recharge studies are essential for investigating the feasibility of using the reclaimed lands in Singapore for subsurface storage and recovery of water. Through time‐series and spectral analyses, net recharge percentages and stress‐filtering characteristics at the reclaimed land were found to depend strongly on the stress transfer velocity, which was a combined function of rainfall pattern and vadose zone thickness. Based on stress transfer velocity, a theory was established to provide logical explanations for the rainfall–recharge relationship, the observed stress‐filtering characteristics and the recharge percentage characteristics at the unconfined sandy aquifer. Although the reclaimed land site has a lithollogically homogeneous soil profile, a non‐uniform recharge pattern was observed to be influenced pronouncedly by the uneven density distribution of bush grasses. Under a bare soil condition, significantly lower recharge percentages were observed for areas under the influence of offshore tides. The unconfined sandy aquifer appears to dampen out the wave propagation of offshore tides rapidly within a short distance from the tidal source, though it has a fairly straight shoreline and is created from highly compacted sand fills. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
63.
Mesozoic fill-sequences in Hefei Basin: Implication for Dabie Orogenesis, central China 总被引:2,自引:0,他引:2
A research on the Mesozoic fill-sequences of Hefei basin, located at the north foot of Dabie Mountains, shows two-phase evolution.
The first phase, early- to mid-/late-Jurassic, is characterized by terrestrial clastic deposits, with four times of reverse-grading
units at least, and forms greatly thick molass reconstruction in the mid-/late-phase, which reflects gradually strong thrusting-orogenesis
in the north Dabie and flexural depression in the north foreland of Dabie Mountains. The second phase, late-Jurassic to Cretaceous,
includes two-episode rifting processes. The first episode (J3) shows calc-alkalic and alkali volcanic rocks interstratified pyroclastic rocks, which may reflect upwelling igneous magma
from mantle-source due to the Yangtze continent slab breakoff induced by deep subduction process. A suite of lacustrine, fluvial
and piemount facies, about 3000 –3500 m in thickness, develops in the second episode (J3-K1), which reflects regional extensional setting and intense elevator diversity of mountain-basin in the study area. This research
renews and deepens cognition for the Mesozoic Dabie orogenesis 相似文献
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ZHU Jingquan LI Yongtie JIANG Maosheng & CHEN Daizhao . Institute of Geology Geophysics Chinese Academy of Sciences Beijing China . Research Institute of Petroleum Exploration Development CNPC Beijing China 《中国科学D辑(英文版)》2004,47(3)
Since Schlanger and Jenkyns (1976)[1] first ad-vanced the ?oceanic anoxic events ?(OAEs) model to explain the origin of the worldwide distributed Early Cretaceous Aptian-Albian (115—103 MaBP) and Late Cretaceous Cenomanian-Turonian (95—88 MaBP) black shales, the OAEs and responses to them have been one of the 揾ot spots?in geological circles. Up till now, researchers at home and abroad have exten-sively studied the sedimentary and geochemical re-sponses to the two anoxic events, espe… 相似文献
67.
机载高分辨率SAR图像直接对地定位原理及精度分析 总被引:1,自引:1,他引:1
依据机载SAR成像的原理,给出了一种实用的机载SAR直接对地定位公式,并结合获取的高分辨率图像进行了定位纠正,取得了较好的效果。根据机载SAR图像对地定位的原理,推导了定位误差的传播公式,并进行了一些误差模拟研究。 相似文献
68.
氡,汞测量用于断裂活动性和分段的研究 总被引:25,自引:1,他引:25
作者首先给出海原活动断裂带从边沟至硝口的3条较长次级剪切断层,干盐池拉分盆地和边沟推挤构造区内的断层,以及尾端挤压构造区内的六盘山东麓逆断层的气氡,气汞浓度测量结果,然后分析了断层气浓度与断层活动性之间的关系,研究结果表明,测试条件大体一致的基础上,气氡,气汞浓度与断层活动性之间有着明显的对应关系,从而证明了断层气测量方法对于活断层分段和活动性研究是一种有效的手段。 相似文献
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