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121.
利津县城区的地热资源主要赋存于新生代新近纪和古近纪碎屑沉积岩中,热储类型为层状孔隙-裂隙型热储,地热资源类型属热传导型。新近纪馆陶组热储层组与古近纪东营组热储层组是主要的热储层。该文在论述利津县地热地质条件的基础上,对地热开发的经济、社会、环境效益及开发利用前景进行了分析,对地热开发中的尾水排放和回灌问题进行了探讨,最后提出了地热资源开发与管理方面的建议。 相似文献
122.
东营市城区馆陶组热储为新近系松散碎屑岩层状热储,目前地热资源开采量约95万m3/a,回灌是解决热储压力下降与地热尾水排放对环境造成不良影响的最佳措施,该文采用自然回灌试验方法探讨回灌条件下馆陶组热储的渗透性能,并与德州市城区馆陶组热储压力回灌试验成果进行了对比,对该热储的回灌性能进行了分析,为指导该区地热回灌提供了科学依据。 相似文献
123.
人工示踪方法评价地下水入渗补给及其优先流程度——以河北栾城和衡水为例 总被引:1,自引:0,他引:1
利用传统人工示踪剂峰值方法评价地下水入渗补给存在精度低和适用性差等缺点。为此,本文提出了多区模型方法,采用保守型示踪剂溴和氚对河北栾城和衡水地区进行了不同土地利用方式和不同深度下地下水入渗补给评价。结果表明,栾城和衡水地区地下水入渗补给量分别为124.3 mm/a和13.7 mm/a,与传统方法(103.3 mm/a和0.0 mm/a)相比,多区模型方法的评价结果更符合实际。同时对由优先流引起的地下水入渗补给量进行了分析,栾城和衡水地区优先流程度分别为28.7%和2.3%。秸秆覆盖抑制降雨或灌溉水入渗补给地下水,降低优先流程度,而植被覆盖有利于土壤水优先流的形成。地下水入渗补给量及其优先流程度与示踪深度均无明显相关性,且受土壤结构控制。 相似文献
124.
针对在地下水资源评价中入渗补给量采用经验估算存在较大误差的问题,以神东矿区为例,在广泛调查矿区包气带岩性结构并结合野外取样、室内参数测定的基础上,采用数值模拟的方法建立包气带水分运移数值模拟模型,定量模拟矿区内不同地段降雨入渗强度,探讨影响降雨入渗强度的主要因素,计算得出研究区降雨入渗系数大致在0.18~0.27,分析认为影响降雨入渗强度的因素有降雨量、潜水埋深、包气带岩性等。其中在研究区广泛分布的风积沙对地下水资源起到了一定的保护作用。 相似文献
125.
SADIKI Moulay Lhassan EL MANSOURI Bouabid BENSEDDIK Badr CHAO Jamal KILI Malika EL MEZOUARY Lhoussaine 《地下水科学与工程》2014,7(3):224-236
In arid and semi-arid zones, water is the most vulnerable resource to climate change. In fact, various techniques such as artificial recharge are adopted to restore aquifers and to ensure aquifer sustainability in relation to the accelerated pace of exploitation. Morocco is a Mediterranean country highly vulnerable to climate change, many of its main aquifers are subjected to excessive drawdowns. This technique is practiced to increase potentiality of these aquifers. In the Northwestern area of Morocco, the significant development experienced by Tangier City in the industrial, tourism, and commercial sectors will lead to increased water requirements-up to 5 067 L/s (159.8 mm3) by 2030. However, the Charf El Akab aquifer system, subject to artificial recharge, is the only groundwater resource of Tangier region; hence, a rational management context is needed to ensure aquifer sustainability, and optimized exploitation under the background of differing constraints, such as increased water requirements, and climate change impacts. This work aims to respond, for the first time, to the Charf El Akab aquifer overexploitation problem, and to evaluate the future scenarios of its exploitation in the event of failure of one of the superficial resources. This work also presents a synthesized hydrodynamic modeling based on the results of the numerical simulations carried out using Feflow software for 2004 (date of cessation of injections) and 2011 (date of resumption of these facilities), making it possible to evaluate the impact of the artificial recharge on the piezometric level of the aquifer on a spatiotemporal scale. Finally, the exploitation scenarios have shown that the aquifer of Charf El Akab will not adequatly provide for the region's water requirements on the future horizon, entailing an optimal management of water resources in the region and an intentionally increased recharge rate. 相似文献
126.
目前基坑管井回灌设计及优化尚无专门成熟的方法,通过不同基坑回灌类型的分析,提出了基坑管井回灌设计原则及设计流程,并对回灌参数进行了探讨,对回灌可施加的最大压力进行了分析,通过285组基坑水文地质数值模型的计算,对比分析了不同渗透各向异性系数、回灌井结构、回灌井位置和保护建(构)筑物位置下的渗流特征,提出了回灌设计综合指数,从经济、技术及施工难度角度综合评估回灌对保护建(构)筑物以及对坑内降水的双重作用,指导抽灌一体化设计。 相似文献
127.
Journal of Geographical Sciences - Groundwater resources have always been some of the most valuable resources of human settlements. Climate changes and ever-increasing water demands registered in... 相似文献
128.
THE PRECIPITATION INFILTRATION AND RUNOFF RECHARGING EXPERIMENT OBSERVATION IN THE TAKLIMAKAN DESERT
1 INTRODUCTIONThelocalprecipitationismostimportantavailablefreshwatersourceindeserts.TheTaklimakanDesertbelongstoanextremearidbelt.Accordingtoafewyears’limitedobservationdata,itisestimatedthattheprecipitationshouldbeintherangeof30-50mmannually.Howev… 相似文献
129.
Stormwater infiltration systems are a popular method for urban stormwater control. They are often designed using an assumption of one‐dimensional saturated outflow, although this is not very accurate for many typical designs where two‐dimensional (2D) flows into unsaturated soils occur. Available 2D variably saturated flow models are not commonly used for design because of their complexity and difficulties with the required boundary conditions. A purpose‐built stormwater infiltration system model was thus developed for the simulation of 2D flow from a porous storage. The model combines a soil moisture–based model for unsaturated soils with a ponded storage model and uses a wetting front‐tracking approach for saturated flows. The model represents the main physical processes while minimizing input data requirements. The model was calibrated and validated using data from laboratory 2D stormwater infiltration trench experiments. Calibrations were undertaken using five different combinations of calibration data to examine calibration data requirements. It was found that storage water levels could be satisfactorily predicted using parameters calibrated with either data from laboratory soils tests or observed water level data, whereas the prediction of soil moistures was improved through the addition of observed soil moisture data to the calibration data set. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
130.
Although the importance of sustainable soil management is recognized, there are many threats to soils including widespread soil structural degradation. This reduces infiltration through the soil surface and/or the percolation of water through the soil profile, with important consequences for crop yields, nutrient cycling and the hydrological response of catchments. This article describes a broad‐scale modelling approach to assess the potential effect that improved agricultural soil management, through reduced soil structural degradation, may have on the baseflow index (BFI) of catchments across England and Wales. A daily soil–water balance model was used to simulate the indicative BFI of 45 696 thirty‐year model runs for different combinations of soil type, soil/field condition, land cover class and climate which encapsulate the variability across England and Wales. The indicative BFI of catchments was then calculated by upscaling the results by spatial weighting. WaSim model outputs of indicative BFI were within the 95% confidence intervals of the national‐average BFI values given for the Hydrology of Soil Type (HOST ? ) classes for 26 of the 28 classes. At the catchment scale, the concordance correlation coefficient between the BFI from the WaSim model outputs and those derived from HOST was 0·83. Plausible improvements in agricultural soil/field condition produced modest simulated increases of up to 10% in the indicative BFI in most catchments across England and Wales, although for much of southern and northern England the increases were less than 5%. The results suggest that improved soil management might partially mitigate the expected adverse effects of climate change on baseflow to rivers. Healthy, well‐functioning soils produce many additional benefits such as better agricultural yields and reduced pollutant movement, so improved soil management should provide win‐win opportunities for society, agricultural systems and the environment and provide resilience to some of the expected environmental impacts of climate change. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献