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1.
GM(1,1)的周期修正模型及其在泉水流量预测中的应用   总被引:6,自引:2,他引:4  
本文阐述了 GM( 1 ,1 )的残差周期修正模型 ,并将它应用于山西神头泉的流量预测中 ,建立了神头泉流量的 GM( 1 ,1 )周期修正模型 ,对其流量进行了预测 ,为神头泉域岩溶水资源开发利用和保护提供了科学依据  相似文献   
2.
Karst springs of the Zagros Mountains contribute a significant amount to agricultural and human water demands of western and south-western Iran. For an adequate management of available water resources in semi-arid and arid regions, sufficient hydrological monitoring is needed, and hydro-chemical and isotope hydrological data provide important additional information. About 350 water samples were collected from precipitation, river water, and karst springs of the upper part of the Karkheh River Basin (20,895 km2) located between 33°35 and 34°55 North and 46°22 and 49°10 East with elevations ranging from 928 to 3563 m above sea level. Sampling was conducted in monthly time resolution from August 2011 to July 2012. All samples were analysed for hydro-chemical parameters (pH, electrical conductivity, and major ions) and stable isotopes (deuterium, oxygen-18). Isotope values of precipitation indicate a local meteoric water line (Zagros MWL δ2H=6.8 δ18O+10.1; R2=0.99) situated between the Mediterranean MWL and Global MWL. Spring and river water isotope values vary between?7.1 and?4.1 ‰, and?38 and?25 ‰ for δ18O and δ2H, respectively, responding to winter snowmelt and evaporation. This work implements stable isotopes and hydro-chemical information of springs and river water to understand hydrological and hydro-geological interrelations in karstic semi-arid areas and helps to improve the current water resources management practices of western Iran.  相似文献   
3.
The investigation of hydrological processes is very important for water resource development in karst basins. In order to understand these processes associated with complex hydrogeochemical evolution, a typical basin was chosen in Houzai, southwest China. The basin was hydrogeologically classified into three zones based on hydrogen and oxygen isotopes as well as the field surveys. Isotopic values were found to be enriched in zone 2 where paddy fields were prevailing with well-developed underground flow systems, and heavier than those in zone 1. Zone 3 was considered as the mixture of zones 1 and 2 with isotopic values falling in the range between the two zones. A conceptual hydrological model was thus proposed to reveal the probable hydrological cycle in the basin. In addition, major processes of long-term chemical weathering in the karstic basin were discussed, and reactions between water and carbonate rocks proved to be the main geochemical processes in karst aquifers.  相似文献   
4.
采用正交实验法,对中科院广州化灌工程有限公司近年施工的四类溶(土)洞所采用的灌浆材料配比进行了研究,得到优化的室内灌浆材料配方。  相似文献   
5.
3H–3He measurements constitute a well-established method for the determination of the residence time of young groundwater. However, this method has rarely been applied to karstified aquifers and in particular to drip water in caves, despite the importance of the information which may be obtained. Besides the determination of transfer times of climate signals from the atmosphere through the epikarst to speleothems as climate archives, 3H–3He together with Ne, Ar, Kr, Xe data may also help to give new insights into the local hydrogeology, e.g. the possible existence of a perched aquifer above a cave. In order to check the applicability of 3H–3He dating to cave drips, we collected drip water samples from three adjacent caves in northwestern Germany during several campaigns. The noble gas data were evaluated by inverse modelling to obtain recharge temperature and excess air, supporting the calculation of the tritiogenic 3He and hence the 3H–3He age. Although atmospheric noble gases were often found to be close to equilibrium with the cave atmosphere, several drip water samples yielded an elevated 3He/4He ratio, providing evidence for the accumulation of 3He from the decay of 3H. No significant contribution of radiogenic 4He was found, corresponding to the low residence times mostly in the range of one to three years. Despite complications during sampling, conditions of a perched aquifer could be confirmed by replicate samples at one drip site. Here, the excess air indicator ΔNe was about 10 %, comparable to typical values found in aquifers in mid-latitudes. The mean 3H–3He age of 2.1 years at this site presumably refers to the residence time in the perched aquifer and is lower than the entire transit time of 3.4 years estimated from the tritium data.  相似文献   
6.
An experimental study was carried out to investigate the resuspension of heavy particles of a sediment bed by axi-symmetric turbulent jets issuing from below. The case of point jets and loosely-held monodispersed particles was considered, in particular, the cases of a single jet and an array of jets located in the intersection points of a square grid. The aim was to map the flow field and the nature of sediment distribution as a function of governing parameters and to parameterize salient observables such as the maximum height of rise of sediments. The results were extrapolated to study sediment resuspension in karstic lakes, especially lake Banyoles located in Catalonia, northeastern Spain.  相似文献   
7.
8.
结合中科院广州化灌工程有限公司采用灌浆技术处理不同类型的溶(土)洞的施工案例,对灌浆材料的选用原则、处理措施、施工工艺及保证措施、检测方法进行了系统的总结,为处理同类地质条件下的溶(土)洞加固工程提供有价值的分析。  相似文献   
9.
刘俊杰  李永化 《力学学报》1998,6(2):160-165
本文以大同煤田区域地质构造特征为基础, 对门帘石的定义、岩性特征、形态与产状、分布和成因进行了分析研究, 指出其与井田发育的准同生岩溶陷落柱具有成生联系。因此, 门帘石的存在具有重要的地质与生产意义。  相似文献   
10.
岩溶隧道突水灾害具有“强突发、高水压、大流量、多类型”等显著特点,其灾变演化过程复杂、动力失稳规律尚不清楚.本文系统提出了不同类型突水灾害的发生条件、判据及安全厚度分析方法,剖析了近期研究进展及发展趋势.首先,给出了隧道突水灾害的概念、类型及构成三要素,从系统论角度分析了隧道突水的灾变过程;其次,总结了隧道突水灾害致灾机理、力学模型、失稳判据和最小安全厚度等方面的近期研究成果;最后,从构成三要素角度分析了隧道突水致灾机理方面的现状与问题,并提出了今后的发展趋势与方向,主要有:(1)灾害源固液气三相置换机制与释能模式,(2)突水通道多相物质迁移与流态演化规律,(3)隔水阻泥结构动力灾变演化机理,(4)突水通道破裂形成过程的模拟分析方法等.  相似文献   
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