共查询到19条相似文献，搜索用时 125 毫秒
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地下水动态的异常变化既有可能是地震前兆异常信息,也有可能是某种环境干扰所引起,如降雨和地下水开采等.如何及时识别并排除环境干扰,对于成功判定地震前兆异常至关重要.云南姚安井水位于2009年10月后出现了下降趋势的异常变化,截止2011年底,最大下降幅度达3m.为分析该井水位异常变化的形成原因,依据姚安井水文地质环境特征,建立了相关的数学物理模型,定量分析了降水量和地下水开采量对该井水位的影响.分析结果表明,姚安井2009年后出现的水位大幅下降可能与区域降水量减小导致的地下水开采活动增强有一定的相关性.文中所采取的异常识别与分析方法,对今后地下水动态异常识别及前兆信息判定工作具有一定的借鉴意义. 相似文献
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地下水动态的异常变化既有可能是地震前兆异常信息, 也有可能是某种环境干扰所引起, 如降雨和地下水开采等. 如何及时识别并排除环境干扰, 对于成功判定地震前兆异常至关重要. 云南姚安井水位于2009年10月后出现了下降趋势的异常变化, 截止2011年底, 最大下降幅度达3 m. 为分析该井水位异常变化的形成原因, 依据姚安井水文地质环境特征, 建立了相关的数学物理模型, 定量分析了降水量和地下水开采量对该井水位的影响. 分析结果表明, 姚安井2009年后出现的水位大幅下降可能与区域降水量减小导致的地下水开采活动增强有一定的相关性. 文中所采取的异常识别与分析方法, 对今后地下水动态异常识别及前兆信息判定工作具有一定的借鉴意义. 相似文献
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根据地下流体前兆异常落实工作指南,对福建闽清梅埔井水位大幅下降的成因作分析,通过观测技术系统故障、水口水库排水干扰、趋势动态、抽水干扰等因素的排除,认为闽清梅埔井水位呈规律性下降是固体潮固有韵律,非外界干扰引起;而水位大幅下降则有可能是区域应力情况的真实反映,可能反映了井区周围断裂活动的加剧。 相似文献
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识别地下水动态地震前兆异常,必须根据观测井地质及水文地质条件,分析地下水的多年动态特征,影响水位的干扰因素及异常变化与地震活动的关系。本文通过上述分析,认为大同6.1级地震前,河北省地下水网中万全、雄县、完县三口井存在水位异常变化。 相似文献
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分析华北地区 2 0余年地下水动态与强地震活动的关系 ,发现部分井水位动态在几次强地震前短期阶段出现形态相似的下降变化 .其特征表现为水位以突变下降或加速下降开始 ,转折后变为速率较缓慢的上升 ,其幅度比下降幅度小得多 ;地震发生在水位缓慢上升过程 ,震时或震前水位大幅度上升 .这种下降形态的异常在华北地区上百口观测井中记录虽然不多 ,但是在几次强地震前不同的井记录了形态相同的水位变化过程 .表明地下水的地震前兆异常具有一定的重现性 ,在不同的强地震前可重复出现 .因此 ,有必要研究这类异常的成因及其与强地震活动的关系 . 相似文献
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分析华北地区20余年地下水动态与强地震活动的关系，发现部分井水位动态在几次强地震前短期阶段出现形态相似的下降变化. 其特征表现为水位以突变下降或加速下降开始，转折后变为速率较缓慢的上升，其幅度比下降幅度小得多；地震发生在水位缓慢上升过程，震时或震前水位大幅度上升. 这种下降形态的异常在华北地区上百口观测井中记录虽然不多，但是在几次强地震前不同的井记录了形态相同的水位变化过程. 表明地下水的地震前兆异常具有一定的重现性，在不同的强地震前可重复出现. 因此, 有必要研究这类异常的成因及其与强地震活动的关系. 相似文献
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Groundwater pumping from aquifers in hydraulic connection with nearby streams has the potential to cause adverse impacts by decreasing flows to levels below those necessary to maintain aquatic ecosystems. The recent passage of the Great Lakes‐St. Lawrence River Basin Water Resources Compact has brought attention to this issue in the Great Lakes region. In particular, the legislation requires the Great Lakes states to enact measures for limiting water withdrawals that can cause adverse ecosystem impacts. This study explores how both hydrogeologic and environmental flow limitations may constrain groundwater availability in the Great Lakes Basin. A methodology for calculating maximum allowable pumping rates is presented. Groundwater availability across the basin may be constrained by a combination of hydrogeologic yield and environmental flow limitations varying over both local and regional scales. The results are sensitive to factors such as pumping time, regional and local hydrogeology, streambed conductance, and streamflow depletion limits. Understanding how these restrictions constrain groundwater usage and which hydrogeologic characteristics and spatial variables have the most influence on potential streamflow depletions has important water resources policy and management implications. 相似文献
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Numerical groundwater modelling as an effective tool for management of water resources in arid areas
Mohamed El Alfy 《水文科学杂志》2013,58(6):1259-1274
AbstractGroundwater, possibly of fossil origin, is used for water supply in some arid regions where the replenishment of groundwater by precipitation is low. Numerical modelling is a helpful tool in the assessment of groundwater resources and analysis of future exploitation scenarios. To quantify the groundwater resources of the East Owienat area in the southwest of the Western Desert, Egypt, the present study assesses the groundwater resources management of the Nubian aquifer. Groundwater withdrawals have increased in this area, resulting in a disturbance of the aquifer’s natural equilibrium, and the large-scale and ongoing depletion of this critical water reserve. Negative impacts, such as a decline in water levels and increase in salinity, have been experienced. The methodology includes application of numerical groundwater modelling in steady and transient states under different measured and abstraction scenarios. The numerical simulation model developed was applied to assess the responses of the Nubian aquifer water level under different pumping scenarios during the next 30 years. Groundwater management scenarios are evaluated to find an optimal management solution to satisfy future needs. Based on analysis of three different development schemes that were formulated to predict the future response of the aquifer under long-term water stress, a gradual increase in groundwater pumping to 150% of present levels should be adopted for protection and better management of the aquifer. Similar techniques could be used to improve groundwater management in other parts of the country, as well as other similar arid regions.
Editor D. Koutsoyiannis; Associate editor X. Chen 相似文献
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Zhang Suxin 《中国地震研究》2007,21(4):428-436
The overexploitation of underground water leads to the continuous drawdown of groundwater levels, change of water quality and dry-up in dynamic water level observation wells. Due to land subsidence, the well pipes uplift and the observation piping systems are damaged. These environmental geology problems can present serious difficulties for the identification of earthquake anomalies by groundwater level observation. Basied on hydrogeological theories and methods, the paper analyzes the relations of the water balance state of aquifers with stress-strain conditions and the water level regime, and then discusses preliminarily the theory and method for identifying well water level anomalies in a groundwater overdraft area. The result shows that we can accurately judge the nature of the anomaly according to the diffusion character of the drawdown funnel in the well area in combination with the aforementioned theory and method and multi-year variation patterns obtained from existing data. The results of the research are helpful for distinguishing the influence of single centralized water pumping from the long-term overdraft of water on the water level, correctly recognizing water level anomalies in the groundwater overdraft area and increasing the level of earthquake analysis and prediction. 相似文献
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Groundwater is the major water resource in Jordan and most of the groundwater basins are already exploited beyond their estimated safe yield. Azraq basin is one of the most important groundwater basins in Jordan, which supplies Amman with drinking water. However, due to overpumping from the shallow groundwater aquifers, the water level dropped dramatically and signs of salinization and depletion are starting to occur. The severe drawdown in the Azraq well‐field caused a reverse in the hydraulic gradient and consequently, the saltwater in the center of the basin (Qa‐Azraq) started to move in the direction of the well‐field. The salinization in the shallow aquifer (basalt/B5/B4) is believed to result from one of the following scenarios: (i) a reverse flow from Sabkha to the AWSA well field, (ii) an upward leakage from the middle aquifer system (B2/A7) and the combined B3 Aquitard‐B2/A7 aquifer, (iii) a dissolution process between the water and rock matrix due to lowering of the dynamic water levels during pumping which reached the mineralized formations underlying the Basalt. The salinization trend of some AWSA wells represented by the gradual increase of major ions is associated with rather constant stable isotopic contents. This indicates that these constituents originate from the main minerals existing in the matrix of the aquifers and thus this scenario is the most likely to occur. 相似文献
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长期过量开采地下水,使地下水位持续下降、水质发生变化,动水位观测井断流;地面沉降造成井管上窜,观测管路系统被损坏等,这些现象对地震地下流体观测地震前兆异常的正确判断带来很大困难。应用水文地质理论与方法,分析含水层的水均衡状态、应力-应变状态及其与水位动态的关系,初步探讨了超采区井水位异常性质的理论与方法。结果表明,根据井孔所在区水位下降漏斗的扩散特征,结合以上所提到的理论和方法,依据资料多年变化特征,可以较准确地判断异常的性质。研究结果有助于区分单一集中抽水与长期地下水超采对水位观测的影响,有助于正确识别超采区水位前兆异常,有助于地震分析预报水平的提高 相似文献
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Groundwater use by vegetation in a tropical savanna riparian zone (Daly River, Australia) 总被引：2，自引：0，他引：2
Sbastien Lamontagne Peter G. Cook Anthony O'Grady Derek Eamus 《Journal of Hydrology》2005,310(1-4):280-293
Soil water matric potentials (Ψm) and the deuterium (δ2H) composition at natural abundance levels of xylem water, soil water, river water and groundwater were used to evaluate whether trees use groundwater during the dry season in the riparian zone of the Daly River (Northern Territory, Australia). Groundwater was a significant source of water for plant transpiration, probably accounting for more than 50% of the water transpired during the dry season. Groundwater use occurred either when trees used water from the capillary fringe or when low Ψm induced by soil water uptake lifted groundwater in the vadose zone. Several water use strategies were inferred within the riparian plant community. Melaleuca argentea W. Fitzg and Barringtonia acutangula (L.) Gaertn. appeared to be obligate phreatophytes as they used groundwater almost exclusively and were associated with riverbanks and lower terraces with shallow (<5 m) water tables. Several species appeared to be facultative phreatophytes (including Cathorium umbellatum (Vahl.) Kosterm. and Acacia auriculiformis A. Cunn. ex Benth.) and tended to rely more heavily on soil water with increased elevation in the riparian zone. The levee-bound Corymbia bella K.D. Hill and L.A.S. Johnson mostly used soil water and is either a facultative phreatophyte or a non-phreatophyte. The temporal variability in groundwater utilisation by the trees is unclear because the study focused on the end of the dry season only. A decline in the regional water table as a result of groundwater pumping may affect the health of riparian zone vegetation in the Daly River because groundwater use is significant during the dry season. 相似文献
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结合观测井孔的水文地质条件、大气降水资料 ,深入剖析了华北地区水位、水氡的中期和转折型短期异常变化的直接原因 ,认为水位异常是由于降水量的增大与减少造成的 ,其形成机制主要为降水渗入补给 ;水氡异常的形成原因主要为降水渗入 -混合机制。进而提出“深浅构造的互动作用” ,用以解释流体异常与地震的关系 ,其论点是 :降水、地下水变化可诱发 (活化 )浅层的构造变动 ,而浅层构造活动又引发深部构造活动和地震的发生 ;反之 ,深部构造的活动和地震的孕育 ,使浅层岩石的应力增强 ,在降水、地下水的诱发作用下 ,可导致浅层的构造活动。降水引起的地下水异常是一种广义的地震前兆 相似文献
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水化学分析方法在地下水异常核实中的应用 总被引：1，自引：0，他引：1
地震前兆识别中的异常核实工作是提高地震分析预报能力的重要环节。"四图一法"是地下水异常核实中有效的水化学分析方法,其中Piper图和Schoeller图用于判定地下水化学类型和补给关系,Gibbs图用于判定地下水化学成分来源,Giggenbach三角图用于判定地下水的水岩平衡状态和是否有深部活动信息,以及混合比例法用于计算地下水的混合程度。同时,介绍了水化学分析方法在异常核实应用中的水样采集、测试方法和基本原理。使用水化学分析方法,有助于判定异常的构造或非构造活动影响因素,提高异常判定的科学水平。 相似文献