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1.
Modeling hydrological responses of karst spring to storm events: example of the Shuifang spring (Jinfo Mt., Chongqing,China) 总被引：4，自引：0，他引：4
Reproduction of hydrographs at karst springs has been an approach of understanding the karst aquifer, which normally acts
as drains for the groundwater flow. However, its numerical modeling is difficult since factors for the internal geometry and
connectedness are unknown and hard to quantify. Hydrographs of the karst aquifer with well-developed conduits in Shuifang
spring catchment were obtained from the automatic gauging station at the spring orifice. Data as to the conduit system were
also obtained based on results and analyses of tracer tests. With these data, the hydrological responses of Shuifang spring
to storm events were simulated by storm water management model (SWMM) developed by USA EPA (Environmental Protection Agency).
Nash–Sutcliffe efficiencies are used to compare the computed flow to the observed, which are 0.95 and 0.92 for calibration
and validation. SWMM was verified and applicable in karst conduit drainage system. The model illustrated correctly quick recharge
through conduits and slow and low inflow from the fissured aquifer matrix. The SCS-CN (soil conservation service-curve number)
infiltration method was used for computation of losses and runoff. Field tests indicated that permeability was extremely high
but different in karst area, which was less sensitive to the computed runoff when exceeded the common value provided by SWMM.
Therefore, an improved quantitative infiltration model for karst area will make SWMM possible to be a useful tool for assessing
and reproducing spring hydrographs. 相似文献
2.
Eulogio Pardo-Igúzquiza Peter Dowd Antonio Pulido Bosch Juan A. Luque-Espinar Javier Heredia Juan J. Durán-Valsero 《Hydrogeology Journal》2018,26(8):2617-2627
A mathematical model of a highly heterogeneous functioning karst aquifer is described. The aquifer is in a high-relief karst massif and, as is common for such locations, data are scarce and there are no borehole, piezometer or pumping-test data. The scarcity of data in this case required a parsimonious approach to ensure that the level of complexity of the model was commensurate with the amount, type and quality of the available data. Parsimony also requires the model to include the minimum essential components that account adequately for the data, which in this and similar cases are the functional dualities of the karst system: duality in recharge, flow and discharge. The model is three-dimensional (3D) in the sense that the aquifer is discretized into 3D voxels, although the flow is one-dimensional (1D) and vertical in the vadose zone, and horizontal and two-dimensional (2D) in the saturated zone. The parsimonious model was designed by coupling a 1D unsaturated gravity-driven flow along the vertical (along each column of voxels that discretize the aquifer) and a 2D unconfined Darcy flow in the saturated zone. In the context of this type of aquifer, preferential recharge through the network of karst conduits implies a rapid rise in the water table, the location and extension of which are model parameters. The karst springs are simulated by drains. The methodology, which is completely general, is illustrated by application to the karst aquifer in the Sierra de las Nieves mountains in southern Spain. 相似文献
3.
Mitja Janža 《Environmental Earth Sciences》2010,61(5):909-920
Karst aquifers are known for their heterogeneity and irregular complex flow patterns which make them more difficult to model
and demand specific modeling approaches. This paper presents one such approach which is based on a conceptual model. The model
was applied in a karst area of the catchment of Rižana spring (200 km2). It is based on the MIKE SHE code and incorporates
the main hydrological processes and geological features of the karst aquifer (diffuse and concentrated infiltration, allogenic
recharge, quick and slow groundwater flow, shifting groundwater divides and groundwater outflow from the catchment area).
Modeling of evapotranspiration and flow in the upper part of the unsaturated zone is more detailed. For the modeling of groundwater
flow in the karst aquifer, a conceptual model was applied which uses drainage function for the simulation of groundwater flow
through large conduits (karst channels and large fissures). The model was calibrated and validated against the observed Rižana
spring discharge which represents a measured response of the aquifer. The results of validation show that the model is able
to adequately simulate temporal evolution of the spring discharge, measured by Nash–Sutcliffe coefficient (0.82) as well as
overall water balance. 相似文献
4.
Nataša Ravbar Juan Antonio Barberá Metka Petrič Janja Kogovšek Bartolomé Andreo 《Environmental Earth Sciences》2012,65(8):2259-2272
In this study a multi-tracer test with fluorescent tracers was combined with time series analyses of natural tracers to characterize
the dynamics of the solute transport through different recharge pathways and to study hydraulic behaviour of a binary karst
system under low-flow conditions. Fluorescent tracer testing included the introduction of uranine, amidorhodamine G, or naphthionate
at three injection points. Sampling and monitoring took place at two karst springs (Malenščica, Unica) and at two underground
rivers (Pivka, Rak) recharging the Unica River at the Polje of Planina, SW Slovenia. Other monitored parameters included precipitation,
spring or underground river discharge, water temperature, and electrical conductivity. Water samples were collected and analyzed
for total organic carbon, Mg2+, SO4
2−, and NO3
− in the laboratory. In the study area, results of the tracer test suggest that contaminant transport in karst may be retarded
for several weeks during low-flow conditions followed by increases in contaminant concentrations after subsequent rainfall
events. Based on interpretation of tracer concentration breakthrough curves, low apparent dominant flow velocities (i.e.,
between 5.8 and 22.8 m/h through the well developed karst conduits, and 3.6 m/h through the prevailing vadose zone with a
dominant influence of a diffuse recharge) were obtained. Together with analyses of hydro-chemographs the artificial tracing
identified different origins of water recharging the studied aquifer. During prolonged low-water conditions the Malenščica
spring is mainly recharged from the karst aquifer and the Unica spring by the sinking Pivka River. After more intensive rainfall
events allogenic recharge from Cerknica prevails in the Malenščica spring, while the Unica spring drains mainly the allogenic
water from the Pivka Valley. These findings of alternating hydraulic connections and drainage areas due to respective hydrological
conditions are important and should be considered when monitoring water quality, implementing groundwater protection measures,
and optimizing future water exploitation. 相似文献
5.
在详细调查基础上,采用系统科学及水文地质分析方法,依据地形地貌、地层岩性、地质构造、示踪试验、地下水排泄基准面、喀斯特发育条件及发育规律等剖析论证流域边界,并通过钻探及示踪试验进行验证。研究结果:（1）对泸西喀斯特断陷盆地南东部的水系统边界向北移进行了修正,证实了三塘一带深部不发育的喀斯特是地下水分水岭边界,使得泸西喀斯特断陷盆地流域的径流系统和边界圈化更加准确;（2）泸西喀斯特断陷盆地流域地表水、地下水转化频繁,地表水径流特征主要以小江河在水库、河流、伏流间的径流转化过程为体现,地下水在侵溶山区接受大气降水补给后,上层径流以泉、暗河的形式在泸西盆地底面排泄后转化成地表水,最终汇集于盆地南部、通过工农隧洞及落水洞排向小江,而下层径流则以小江水面为基准,通过深层径流排泄。 相似文献
6.
Characterization of karst conduits by tracer tests for an artificial recharge scheme 总被引：1，自引：0，他引：1
Challenged by rapidly changing climate in combination with an increase in anthropogenic pressures, karst groundwater resources in the Old Town of Lijiang (OTLJ), SW China, are diminishing. Higher frequency and longer duration of dried-up periods have been observed at the Heilongtan Park (HP) Springs in recent years. Thus, there is an urgent need for an artificial recharge scheme, aimed at replenishing groundwater in the aquifer and increasing the outflow of the springs to ensure effective water resources management. Evaluation of the scheme feasibility, prior to its implementation, is important. In this study, tracer tests were conducted between the recharge area and receiving springs in order to gain insight into the transport mechanisms of karst groundwater and the structural characteristics of the aquifer. Multiple underground flow paths, exhibiting high conductivity between the recharge area and HP Springs, were revealed by the interpretation of tracer breakthrough curves. Three springs considered as the leakages of the scheme were identified. Moreover, the outflow of springs at HP and OTLJ were predicted to be increased by the artificially recharged water after 9.2 and 12.5 days, respectively. Quantitative analysis of tracer recoveries demonstrates that the springs to be recharged and the springs considered as leakages, respectively, share 45 and 55% of the increased outflow. The feasibility of the scheme has been confirmed by the tracer tests. This report provides references for the evaluation of artificial groundwater recharge and protection strategies, particularly in large and poorly investigated karst spring fields.
相似文献7.
Functioning of a karst aquifer from S Spain under highly variable climate conditions,deduced from hydrochemical records 总被引：2，自引：2，他引：0
Over a period of three hydrological years during which precipitation was highly variable, measurements of discharge, electrical conductivity, temperature and chemical components of the water at the Cañamero spring (southern Spain) were taken in order to characterise the hydrogeological functioning of the karst aquifer that it drains. The results obtained from analysis of the frequency distribution of electrical conductivity data revealed histograms with a plurimodal morphology (up to 5 modes) and a range of variation that increased with greater pluviometry during the study period. The discharge from this spring increased sharply a few days after major rainfall episodes and, when the discharge reached a value of approximately 3.73 m3/s, an overflow spring started to function. During high-water periods, there were sudden and large falls in EC, temperature and all the chemical components dissolved in the water. This high variability reflects the predominance of groundwater flow through karst drains, a typical feature of conduit flow systems. The considerable hydrochemical heterogeneity observed is caused by the mobilisation of important volumes of recharge waters from shallow areas of the aquifer (soil, epikarst) towards the discharge point, with greater participation of the unsaturated zone during high-water conditions, and a more active role played by the saturated zone during low-water conditions. In karst systems such as the one drained by the Cañamero spring, it is important to monitor several responses (hydrodynamic, hydrothermal, hydrochemical, etc.), with an appropriate sampling frequency and under different hydrometeorological conditions, in order to achieve an adequate hydrological characterisation. This is fundamental for planning, management and protection of groundwater in karst aquifers. 相似文献
8.
In karst areas, groundwater movement is dominated by conduit flow; thus, understanding the distribution and structure of karst conduits has great significance for water research, groundwater protection and engineering construction. With the Dafengdong (Guizhou Province, China) underground river karst as an example, a mise-a-la-masse method, tracer tests and cave detection were conducted to study the distribution and structure of karst conduits. Combined with information on the geological and hydrogeological conditions, the geological factors that form karst conduits were determined. It can be concluded that: (1) Under the influence of faults, karst conduits usually develop towards or along faults; (2) multiple karst conduits form easily on both sides of tectonic fracture zones; (3) both lithology and geological structure affect the formation of blue holes, and when the directions of karst conduits change, blue holes easily form in weak parts of the structure; (4) at springs where two aquifers intersect, with strong chemical dissolution of the lower karst aquifer and mechanical collapse of the upper aquifer, blue holes also form easily; and (5) integrated mise-a-la-masse method, tracer tests and cave detection can accurately discern the distribution and structure of karst conduits. Geological factors can be used to preliminarily delineate the distribution and structure of karst conduits in similar areas based on hydrogeological conditions. Such methods hold great significance for groundwater extraction and protection and engineering construction in karst areas.
相似文献9.
降雨对裂隙型岩溶含水系统演化影响的数值模拟研究 总被引：5，自引：5，他引：0
本文在构建有降雨入渗及河流补给的裂隙型岩溶含水系统的概念模型基础上,采用有限差分数值方法,利用裂隙渗流立方定律及Dreybort（1996）经过实验总结出的碳酸钙溶蚀经验公式,定量地计算了裂隙型岩溶含水系统经过10 000年溶蚀的演化形态及岩溶泉的变化。模拟发现,岩溶含水系统的溶蚀主要发生在降雨入渗面处、河流补给处和岩溶泉的出露点附近。随着溶蚀的进行,岩溶含水系统的潜水位不断下降部分岩溶泉被疏干,通过计算岩溶泉汇流管道的隙宽变化,发现岩溶含水系统会出现明显的差异性溶蚀。在模拟过程中调节降雨量的大小发现降雨入渗对有河流补给的岩溶含水系统的演化影响并不显著。 相似文献
10.
《Applied Geochemistry》2005,20(11):2063-2081
This paper deals with chemical and isotope analyses of 21 springs, which were monitored 3 times in the course of 2001; the monitoring program was focused on the groundwater of the Gran Sasso carbonate karst aquifer (Central Italy), typical of the mountainous Mediterranean area.Based on the hydrogeological setting of the study area, 6 groups of springs with different groundwater circulation patterns were distinguished. The hydrogeochemistry of their main components provided additional information about groundwater flowpaths, confirming the proposed classification. The spatial distribution of their ion concentrations validated the assumptions underlying the hydrogeological conceptual model, showing diverging groundwater flowpaths from the core to the boundaries of the aquifer. Geochemical modelling and saturation index computation elucidated water–carbonate rock interaction, contribution by alluvial aquifers at the karst aquifer boundaries, as well as impacts of human activities.The analysis of 18O/16O and 2H/H values and their spatial distribution in the aquifer substantiated the hydrogeology-based classification of 6 groups of springs, making it possible to trace back groundwater recharge areas based on mean isotope elevations; the latter were calculated by using two rain monitoring stations. 87Sr/86Sr analyses showed seasonal changes in many springs: in winter–spring, the changes are due to inflow of new recharge water, infiltrating into younger rocks and thus increasing 87Sr/86Sr values; in summer–autumn, when there is no recharge and spring discharge declines, changes are due to base flow groundwater circulating in more ancient rocks, with a subsequent drop in 87Sr/86Sr values.The results of this study stress the contribution that spatio-temporal isotope monitoring can give to the definition of groundwater flowpaths and hydrodynamics in fissured and karst aquifers, taking into account their hydrogeological and hydrogeochemical setting. 相似文献
11.
《Comptes Rendus Geoscience》2019,351(6):441-450
In humid subtropical regions, baseflow is mainly governed by aquifer discharges and this dynamic is fed by groundwater recharge. To better comprehend the watershed groundwater recharge using a large-scale approach, two watersheds located over the Serra Geral Aquifer System (Southern South America) were studied. Three different groundwater recharge methods were utilized to study the baseflow: a simplified water budget, a hydrograph separation using the Eckhardt filter with different ways of obtaining the BFImax parameter, and the MGB–IPH hydrological model, which is unprecedented in being used for this purpose. These methods showed a general mutual convergence, where recharge magnitude remained similar in most methods. The MGB–IPH model proved to be a useful tool for understanding the occurrence of groundwater recharge. Uncertainties associated with the representativity of interflow demonstrated by hydrograph separation and shown in the model may indicate that the groundwater recharge estimate could be lower than those obtained considering hydrograph numerical filters. 相似文献
12.
拒马源泉群作为拒马河的源头,受到了较多专家和学者的关注。但这些研究多集中在地下水的水化学、水位动态、泉流量等特征上,对地下水氢氧同位素特征的分析几乎没有,且对北海泉的成因解释多为粗略的定性概述。为了说明涞源北盆地地下水的氢氧同位素特征,详细揭示北海泉的形成模式,首次系统地采集了不同含水岩组的地下水样品,测定了水样的氢氧同位素组分。结果表明:样品点δD和δ18O值均落在区域大气降水线上或附近,大气降水是研究区地下水的主要补给来源;白云岩、灰岩含水岩组高程效应较明显,径流途径长,松散含水层径流途径短,受蒸发作用较强;白云岩、灰岩含水岩组和松散含水层氘盈余d值分别为6.0‰～11.6‰、4.2‰～11.2‰、3.8‰～8.0‰,较大气降水大部分偏小,表明岩溶水和松散孔隙水经历了不同的流动过程;白云岩、灰岩含水岩组从补给区向排泄区各自流动过程中,在小西庄、香炉屯村附近断裂带发生沟通混合,然后在向盆地中心径流过程中受断层阻水上升,上升过程中又接受了松散孔隙水的补给,最后在松散岩层中出露成泉,形成北海泉。在孔隙水混入前,两者的平均补给比例大约为48.4%～57.6%和42.4%～51.6%。 相似文献
13.
Karst aquifer studies often focus on allogenic water inputs and large conduit flow. However, diffuse recharge can be significant, particularly in unconfined eogenetic karst aquifers that retain high matrix permeability. This study examines an unconfined region of the upper Floridan aquifer (USA) that hosts a sinking stream, its resurgence, and a large conduit system. Daily diffuse recharge was approximated using a water-budget method and ranged from 17% of precipitation during a low precipitation year to >53% during the highest precipitation year, illustrating the highly variable nature of diffuse recharge in this region. The total allogenic input via the sinking stream over the 5 years of the study was significantly larger than the volume of diffuse recharge. However, only about 2% of the allogenic recharge flows from the conduit into the surrounding aquifer. That flow is restricted to storm events when hydraulic heads in the conduits exceed those in the surrounding aquifer. The estimated volume of dissolution is similar for allogenic recharge and diffuse recharge to the unconfined region surrounding the conduits, but dissolution from the diffuse recharge is distributed over a larger area than dissolution from allogenic recharge. These results exemplify how recharge type impacts flow and water–rock interactions in eogenetic karst aquifers. 相似文献
14.
Karst groundwater is one of the important water resources for people in the world. There is an estimate that by 2028 karst
groundwater will supply more than 80% of people in the world. However, several areas in the world are characterized by high
nitrate concentrations in karst aquifers. In China, karst groundwater is also threatened by extensive use of fertilizer and
pesticides, industry waste, septic systems and poultry, hog or cattle manure. In order to understand the water quality of
a subterranean river in south China, especially the dynamic variation of nitrate, nitrogen input and output were determined
via auto-monitored apparatus, manual observation and samples from 2004 to 2008 in Guancun subterranean river drainage area.
Land use and anthropogenic activities were also investigated frequently. The results showed the range of nitrate variation
was 2.56–15.40 mg l−1, with an average value of 6.60 mg l−1. Spatial variation of nitrate concentrations showed nitrate rose where there were villages and agriculture distribution.
Long series of nitrate and discharge monitoring revealed there was a nitrate peak in spring just before the beginning of rainy
season. Three rainfall events were selected for analysis of relations among hydrological process, water chemistry, and nitrate
of the spring. The flood processes of the spring were divided into three or four phases according to change of water level
and water chemistry. They were dominated by initial condition of aquifer, piston flow in soil and vadose, piston flow in conduit,
diffuse recharge, and bypass recharge. The original condition of aquifer and rainfall pulse controlled recharge flow and changes
of nitrate and hydro-chemical graphs of the spring. The quantity of nitrogen input in a year was 66.61 t, and the output was
21.24 t. Nitrogen leaching loss in base flow accounted for 76.11% in a year. Some measures should be taken to protect karst
water in the very near future, so that health risks to the local people can be decreased. 相似文献
15.
岩溶水系统的水化学曲线及其在水文地质研究中的应用 总被引：5，自引：0，他引：5
为了认识水文地质条件与岩溶泉水化学之间的关系,以西南地区的6个典型岩溶水系统丫吉试验场S31号泉、毛村地下河、官村地下河、陈旗岩溶泉、青木关地下河以及金佛山水房泉为例进行研究。通过对比发现,在这些强烈非均质的山区裸露型岩溶水系统中,仪器能够实现自动化监测的电导率、温度和pH值等指标的水化学曲线存在差异。分析可知控制水化学变化的主要因素如下:首先是降雨补给引起系统的水量与碳酸盐岩溶解过程的变化;其次是CO2气体随降雨进入含水层,促进碳酸盐岩的溶解;最后是地表污染物的淋滤。当电导率、水温、pH曲线出现降低和碳酸盐岩矿物饱和指数下降时,反映的是岩溶水的稀释作用;当电导率曲线出现高峰时,反映的是岩溶水补给的CO2效应,此时水中二氧化碳分压(pCO2)升高;当场雨中水化学曲线的变化滞后于水文动态曲线时,反映的是岩溶管道的活塞流效应;与人类活动有关的NO3-等污染物质量浓度在降雨后出现高峰,反映土壤的降雨淋滤作用,并可能影响电导率的变化趋势。某个系统的水化学曲线趋向于经常出现某几种效应,并且彼此的类型不同,表明了降雨补给的面状渗流方式和集中灌入方式对岩溶水影响的强弱不同,以及系统在径流方式和调蓄机制上的差异。一般而言:以面状补给方式为主的系统,水化学曲线多表现为CO2效应,较少出现稀释作用;而岩溶发育强烈的系统,降雨补给受控于溶蚀裂隙和管道,其水化学曲线较多出现稀释作用,较少出现CO2效应;以管道为主要径流方式的系统易出现活塞流效应,而包气带厚度大和含水层储水能力强的系统水化学变化被减弱。 相似文献
16.
Dynamics and anthropogenic impacts of multiple karst flow systems in a mountainous area of South China 总被引：5，自引：0，他引：5
Mingming Luo Zhihua Chen Robert E. Criss Hong Zhou He Huang Zhaofeng Han Tingting Shi 《Hydrogeology Journal》2016,24(8):1993-2002
The Xiangxi River basin, South China, is a steep terrane with well-developed karst features and an important Cambrian-Ordovician aquifer. Meteoric water in this mountainous area features a mean δ18O elevation gradient of –2.4?‰/km. This gradient was used to estimate mean recharge elevations of 760 m for Shuimoxi (SMX) spring, 1,060 m for Xiangshuidong (XSD) spring, and 1,430 m for drill hole ZK03, indicating multiple flow paths in the Cambrian-Ordovician karst aquifer. Mean residence times of 230 and 320 days and ～2 years were estimated for these features, respectively, using the damped running average model that predicts the isotopic variations in groundwater from those in precipitation. Groundwater in the regional karst flow system has the longest residence time, the highest recharge elevation, the longest flow paths, the lowest addition of anthropogenic components, and the greatest amount of water–rock interaction as indicated by its higher dissolved solids, Mg2+ concentrations and Mg/Ca ratios than the springs. In contrast, the local and shallow karst flow systems respond rapidly to recharge events. Artificial tracer tests prove that these shallow karst systems can also quickly transmit anthropogenic contaminants, indicating that they are highly vulnerable to human impacts, which include the enrichment of NO3 –. The intensity of water–rock interaction and groundwater vulnerability are mainly determined by the structure and dynamics of the multiple karst flow systems. 相似文献
17.
Multi-tracer investigation of groundwater residence time in a karstic aquifer: Bitter Lakes National Wildlife Refuge, New Mexico, USA 总被引：1，自引：1，他引：0
Several natural and anthropogenic tracers have been used to evaluate groundwater residence time within a karstic limestone aquifer in southeastern New Mexico, USA. Natural groundwater discharge occurs in the lower Pecos Valley from a region of karst springs, wetlands and sinkhole lakes at Bitter Lakes National Wildlife Refuge, on the northeast margin of the Roswell Artesian Basin. The springs and sinkholes are formed in gypsum bedrock that serves as a leaky confining unit for an artesian aquifer in the underlying San Andres limestone. Because wetlands on the Refuge provide habitat for threatened and endangered species, there is concern about the potential for contamination by anthropogenic activity in the aquifer recharge area. Estimates of the time required for groundwater to travel through the artesian aquifer vary widely because of uncertainties regarding karst conduit flow. A better understanding of groundwater residence time is required to make informed decisions about management of water resources and wildlife habitat at Bitter Lakes. Results indicate that the artesian aquifer contains a significant component of water recharged within the last 10–50 years, combined with pre-modern groundwater originating from deeper underlying aquifers, some of which may be indirectly sourced from the high Sacramento Mountains to the west. 相似文献
18.
黔东北高原斜坡地区4种岩溶地下水系统模式及特点——基于地貌和蓄水构造特征 总被引：5，自引：0，他引：5
受深切河谷地貌控制,黔东北大部分地区岩溶地下水深埋且排泄于河谷岸边,以快速的管道裂隙流为主,给地下水资源勘探开发带来了极大的困难,局部地区受蓄水构造控制形成勘探有利的地下水富集区。笔者基于地貌和蓄水构造将研究区岩溶地下水系统归纳总结为深切河谷型、向斜山地型、单斜夹层型和背斜槽谷型4类模式。深切河谷型岩溶地下水系统地下水水力坡度大,地下水以快速的管道流为主,排泄点低,开发利用方式建议直接在地下河出口或天窗中抽提地下水,经济效益明显地区可堵洞成库进行综合利用;向斜山地型岩溶地下水系统发育高位岩溶泉或地下河出口,排泄点高,适合直接引水利用;单斜夹层型岩溶地下水系统在岩性接触带出露一系列接触泉,排泄分散,开发利用方式建议直接利用或抽提岩溶泉水,受夹层隔水顶底板影响局部地区可钻井取水;背斜核部出露寒武系白云岩地层,导致背斜槽谷型岩溶地下水系统含水岩层均匀厚度大,分布大量非全排型岩溶泉,地下水开发适合抽提泉水或钻井抽取地下水。 相似文献
19.
Karstic aquifers are considered as the main sources of groundwater in the northeast of Rudbar, Iran. The present study was conducted to evaluate the hydrogeological properties of karstic springs in this region. For this purpose, saturation indices (SI values) were calculated using the geochemical PHREEQC model for a number of minerals in the groundwater in the karstic aquifer. Moreover, AqQA-RockWare software packages were used to prepare hydrogeochemical plots for the aquifer, using which the sources of the ions in the water were identified. The origin of bicarbonate, calcium, and magnesium ions in water was determined using chloro-alkaline indices. Moreover, through plotting a Piper diagram for spring water samples, it was discovered that water type of all springs is the Ca-HCO3 type, confirming the karstic characteristic of springs in the area. A Durov diagram also suggests that the water composition of the springs is of the bicarbonate type with the dominant Ca cation, suggesting the calcareous effects of the region on the quality of groundwater and exhibiting a single source for the springs. The calculated saturation indices show that most of the water samples are undersaturated with respect to calcite, dolomite, and CO2. The stable isotopes (δ18O and δ2H) and deuterium excess values were used to get information about transport pathways in groundwater, atmospheric moisture, and the degree of interaction between these reservoirs. The degree of karstification of the recharge area of the karst aquifer was determined to be 5.5 from an analysis of the hydrograph Sefidab Spring. 相似文献
20.
Rahim Bagheri Hadi Jafari Aliakbar Momeni Fatemeh Bagheri 《Arabian Journal of Geosciences》2016,9(19):731
The recession hydrographs of karst springs provide important information about aquifer characteristics such as storage properties and drainage potential, karstification degree, and other hydrological features. The Faresban, Famaasb, Gonbad-e-Kabood, and Gian springs are the important karst springs which drain main karst aquifers in west of Iran. In this study, we evaluate hydrological characteristics of these four karst springs using different analytic equations. Almost, all the recession curves were well fitted by a function that consists of three main exponential terms. The initial portion of the recession curve represents the fast drainage of large fractures and conduits, ending with the slowly decreasing curve, where the drainage of rock matrix and small fissures or baseflow is dominant. The Gian spring has the largest storage volume but the lowest drained water (7%). Using Mangin’s equation, it is apparent that the baseflow supplies over 85% of the total drained water to the Gian spring, while a small quantity of total outflow is made up of quickflow periods. Of the water available to the Famaasb, Faresban, and Gonbad-e-Kabood springs, 85, 80, and 70% are drained during period of baseflow, respectively, whereas the quickflow periods have minor importance in some springs. Based on the Coutagne’s equation results, it can be concluded that the catchment of the Famaasb and Gonbad-e-Kabood springs have a karstified saturation zone with drainage channels that provide a rapid discharge with little storage capacity. At Gian catchment area, the initial discharge is not as rapid as karstification but is fairly homogeneous throughout the aquifer. 相似文献