Manifestation and measurement of the fractal characteristics of karst hydrogeological formations     

Athanasios J. Maramathas  Andreas G. Boudouvis 《Advances in water resources》2006

A new method of estimating the fractal dimension of the percolation backbone of karst systems, which are discharged through karst springs, is presented. This method is based on the simulation of the spring by the MODKARST deterministic mathematical model. Application has been made to the Psiloritis karst formation in Crete, which feeds the periodically brackish karst spring “Almiros” in Crete. Furthermore, the estimated dimension justifies an independently determined power law that quantifies the sea intrusion into the karst system.  相似文献   

Effects of glaciations and permafrost upon the development of karst in Canada     

Derek Ford 《地球表面变化过程与地形》1987,12(5):507-521

Canadian examples suggest that karst landforms may be divided into eight types in terms of their temporal relationships to the record of repeated Quaternary glaciations. Two types are postglacial, two are subglacial, one type occurs where glacial features are adapted to karstic drainage, and three types display sequences of karstic and glacial action. Glacier effects upon karst landforms and their underlying aquifers display the gamut of possibilities. They may destroy, inhibit, preserve, or stimulate karst development. Where continuous permafrost is maintained when covered by glacier ice, postglacial karst is limited to the active layer epikarst. Where permafrost is thawed beneath ice or during deglaciation there are a variety of postglacial karst developments, depending in part upon climate and in part upon local lithologic and relief conditions.  相似文献   

广西岩溶区工程地质灾害及场地处理     

杨仕升  蒙雷  何声  梁齐立 《震灾防御技术》2015,10(4):884-891

为减小岩溶区地质灾害带来的损失,以广西岩溶区为例,分析了广西岩溶地质的分布特点,对广西岩溶区的工程地质灾害进行研究分类,对岩溶区工程场地处理方法进行研究,综述了地表封闭防渗法、地面下加固处理法、结构物跨越法三大方法的原理、实施效果和实用性。研究发现:由于降雨和地下岩石类别差异等因素,广西的岩溶分布类型具有强烈的地域特性,形成了三大岩溶地貌特征;产生岩溶区地质灾害最主要的诱因是地下水的变化,重要工程中定时定点监控地下水变化十分重要;广西的岩溶区溶洞和土洞塌陷主要是人为因素造成的。  相似文献   

Quantifying the role of karstic groundwater in a snowmelt-dominated hydrologic system     

Benjamin W. Tobin  Benjamin F. Schwartz 《水文研究》2020,34(16):3439-3447

River discharge in mountainous regions of the world is often dominated by snowmelt, but base flows are sustained primarily by groundwater storage and discharge. Although numerous recent studies have focused on base-flow discharge in mountain systems, almost no work has explicitly investigated the role of karst groundwater in these systems across a full range of flow conditions. We directly measured groundwater discharge from 48 karst springs in the Kaweah River and its five forks in the Sierra Nevada mountains, California, United States. Relationships between spring and river discharge showed that karst aquifers and springs provide significant storage and delayed discharge to the river. Regression models showed that, of all potential seasonal groundwater storage compartments in the river basin, the area of karst (0.1–4.4%) present provides the best explanation of base-flow recession in each fork of the Kaweah River (directly measured contributions from karst springs ranged from 3.5 to 16% during high-flow to 20 to 65% during base-flow conditions). These results show that, even in settings where karst represents a small portion of basin area, it may play an over-sized role in seasonal storage and water resources in mountain systems. Karst aquifers are the single most important non-snow storage component in the Kaweah River basin, and likely provide similar water storage capacities and higher base flows in other mountain river systems with karst when compared with systems without karst.  相似文献   

Interpretation of groundwater level monitoring results in karst aquifers: examples from the Dinaric karst     

Ognjen Bonacci  Tanja Roje‐Bonacci 《水文研究》2000,14(14):2423-2438

The paper presents an attempt to determine the characteristics of karst aquifers using information on groundwater level (GWL) in natural holes and boreholes with different data quantity and time resolution of GWL measurements. In this paper the particulars of karst aquifers were analysed for four examples from the Dinaric karst. In all four study areas, aquifers are formed in bare, deep and well‐developed Dinaric karst consisting of Cretaceous limestones. The first example represents a wide area of Imotsko polje in the karst. The aquifer was analysed on the basis of infrequent water level monitoring in natural karst water features (jamas, lakes, wells) and discharges of springs and rivers. The karst aquifer in this example is complex, non‐homogenous and variable in space and time, which is frequent in the Dinaric karst. Regardless of the aforementioned it was possible to determine its elementary characteristics. The second example represents 10 wells used for the water supply for the city of Pula. The GWL and salinity were measured once a week in the period between 1981 and 1996. Even though these measurements were relatively infrequent in space and time, they served as bases for assessment of average and maximum aquifer conditions as well as boundaries of saltwater intrusion. In the third example only a portion of aquifer of the karst spring Blaz, which is in the contact with the Adriatic Seas, has been analyzed. It is a spring with an intrusion of salt water. For purposes of study of saltwater intrusion, 26 piezometers were drilled in its vicinity in which GWL, salinity and temperature were measured once a day during 168 days, a period comprising one complete cycle of seawater intrusion and retreat. These measurements proved the existence of dispersed discharge from the aquifer into the sea and its non‐homogeneity in space. In the fourth example GWL was measured continuously in 10 deep (up to 300 m) piezometers in the hinterland of the Ombla Spring catchment. The measurement period lasted 2 years (January 1988 to December 1989). The analyses are made with hourly data. The results made it possible to determine numerous characteristics of the karst aquifer and a significant non‐homogeneity of groundwater distribution in karst aquifers, depending more on the underground karst phenomena than the surface karst forms. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

Geomorphic inheritance and the development of tower karst     

Paul W. Williams 《地球表面变化过程与地形》1987,12(5):453-465

Four genetic types of tower karst are identified, the most typical consisting of residual hills protruding from a planed carbonate surface veneered by alluvium. Two extreme possibilities for tower karst evolution are recognized: a direct development that is independent of any previous morphology and a sequential development that depends explicitly on the morphological characteristics of a previous cockpit karst phase. Examples of both are described, although the latter appears the more common. South China tower karst is examined in this light. Palaeomagnetic analysis of cave deposits in a tower near Guilin indicate the feature to be a time-transgressive landform. Four principal controls of tower development are discussed and a model of tower evolution is presented.  相似文献   

Evidence of karst from behaviour of the Asmari limestone aquifer at the Khersan 3 Dam site,southern Iran     

《水文科学杂志》2013,58(1):206-220

Abstract

The Asmari limestone formation is the major aquifer system at the Khersan 3 Dam site, Zagros, Iran. Characterization of the aquifer system and study of karst development are essential for forecasting leakage potential and to plan remediation works. The aquifer functioning and karst structure were evaluated by geology, well hydrodynamics and natural tracing studies, showing one unconfined and three artesian sub-aquifers, the last being characterized by rapid flow, with contributing old recharge water, and a recharge at higher elevation than the unconfined sub-aquifer. The anticline structure outcrops the artesian sub-aquifers downstream of the site. The confining layers disappear and the aquifer system discharges as a mix of all groundwater. Artesian groundwater is estimated to contribute about 80% (dry season) and 50% (wet season) of flow in the mixing zone. Very few karst features are observed in cores and galleries at the site, despite some karst landforms in the reservoir area. However the aquifer exhibits fast flow of karst type in the artesian sub-aquifers.  相似文献   

The use of GIS‐based digital morphometric techniques in the study of cockpit karst     

P. Lyew‐Ayee  H. A. Viles  G. E. Tucker 《地球表面变化过程与地形》2007,32(2):165-179

  相似文献   

Analysis of the karst aquifer structure of the Lamalou area (Hérault, France) with ground penetrating radar   总被引：1，自引：0，他引：1  

Walid Al-fares  Michel Bakalowicz  Roger Gurin  Michel Dukhan 《Journal of Applied Geophysics》2002,51(2-4)

The study site at Lamalou karst spring (Hortus karst plateau) is situated 40 km north of Montpellier in France. It consists of a limestone plateau, drained by a karst conduit discharging as a spring. This conduit extends for a few dozen meters in fractured and karstified limestone rocks, 15 to 70 m below the surface. The conduit is accessible from the surface. The main goal of this study is to analyze the surface part of the karst and to highlight the karstic features and among them the conduit, and to test the performances of ground penetrating radar (GPR) in a karstic environment. This method thus appears particularly well adapted to the analysis of the near-surface (<30 m in depth) structure of a karst, especially when clayey coating or soil that absorbs and attenuates the radar is rare and discontinuous. A GPR pulseEKKO 100 (Sensors and Software) was used on the site with a 50-MHz antenna frequency. The results highlight structures characterizing the karstic environment: the epikarst, bedding planes, fractured and karstified zones, compact and massive rock and karrens, a typical karst landform. One of the sections revealed in detail the main conduit located at a depth of 20 m, and made it possible to determine its geometry. This site offers possibilities of validation of the GPR data by giving direct access to the karstic conduits and through two cored boreholes. These direct observations confirm the interpretation of all the GPR sections.  相似文献   

Assessing the contamination of water flow in Soldatskaya Cave (Crimea)     

S. E. Mazina  A. V. Gopin  A. L. Nikolaev 《Water Resources》2009,36(6):699-705

The contamination of water flow in Soldatskaya Cave is studied. Groundwater of the cave was found to feature bacterial pollution. The distribution of bacterial cells over the karst system is examined. The contamination is shown to correlate with anthropogenic load. The major hydrodynamic and physicochemical characteristics of groundwater flow are evaluated, and their correlation with self-purification is demonstrated. Components of the karst water self-purification mechanisms are analyzed. The possibility to intensify karst water self-purification is considered.  相似文献   

Variation of karst spring discharge in the recent five decades as an indicator of global climate change: A case study at Shanxi,northern China   总被引：3，自引：0，他引：3  

GUO Qinghai  WANG Yanxin  MA Teng & LI Luxiu . School of Environmental Studies  China University of Geosciences  Wuhan  China  . Office of Water Resource Management of Shanxi Province  Taiyuan  China 《中国科学D辑(英文版)》2005,48(11):2001-2010

As one of the largest international scientific pro- grams in geoscience and environmental science, global change studies were initiated in the early 1980s[1,2]. Noticeable achievements have been made in the stud- ies using indicators such as loess, marine sediment, permafrost, vermicular red earth, and even magmatic activity[2―6]. In recent years, the importance of ground- water as a new type of global change indicators has caused wide attention[7]. Stochastic, isotopic and hy- drochemical st…  相似文献   

Studying the Flow Dynamics of a Karst Aquifer System with an Equivalent Porous Medium Model   总被引：2，自引：0，他引：2  

Muath Abusaada  Martin Sauter 《Ground water》2013,51(4):641-650

The modeling of groundwater flow in karst aquifers is a challenge due to the extreme heterogeneity of its hydraulic parameters and the duality in their discharge behavior, that is, rapid response of highly conductive karst conduits and delayed drainage of the low‐permeability fractured matrix after recharge events. There are a number of different modeling approaches for the simulation of the karst groundwater dynamics, applicable to different aquifer as well as modeling problem types, ranging from continuum models to double continuum models to discrete and hybrid models. This study presents the application of an equivalent porous model approach (EPM, single continuum model) to construct a steady‐state numerical flow model for an important karst aquifer, that is, the Western Mountain Aquifer Basin (WMAB), shared by Israel and the West‐Bank, using MODFLOW2000. The WMAB was used as a catchment since it is a well‐constrained catchment with well‐defined recharge and discharge components and therefore allows a control on the modeling approach, a very rare opportunity for karst aquifer modeling. The model demonstrates the applicability of equivalent porous medium models for the simulation of karst systems, despite their large contrast in hydraulic conductivities. As long as the simulated saturated volume is large enough to average out the local influence of karst conduits and as long as transport velocities are not an issue, EPM models excellently simulate the observed head distribution. The model serves as a starting basis that will be used as a reference for developing a long‐term dynamic model for the WMAB, starting from the pre‐development period (i.e., 1940s) up to date.  相似文献   

Glaciokarst landforms and processes of the southern Dinaric Alps          下载免费PDF全文

Manja Žebre  Uroš Stepišnik 《地球表面变化过程与地形》2015,40(11):1493-1505

Glaciokarst is a landscape which combines karst features and hydrology as well as inherited glacial features. It is a result of glaciation upon a karst geomorphological system. The relationship between glaciers and karst is rather poorly known and inadequately recognized. This research focuses on three distinct karst areas along the Adriatic coast in the southern Dinaric Alps that were affected by the Quaternary glaciations. An insight into specific glaciokarst processes and surface features was provided through the study of the areas of the Lov?en, Orjen and Vele? Mountains. A glaciokarst geomorphology is in general well preserved due to the prevailing vertically oriented chemical denudation following de‐glaciation and almost the entire absence of other surface processes. Typical glacial erosional features are combined by a variety of depressions which are the result of a karstic drainage of sub‐glacial waters. The majority of glacial deposits occur as extensive lateral‐terminal moraine complexes, which are often dissected by smaller breach‐lobe moraines on the external side of the ridge. Those moraine complexes are likely to be a product of several glacial events, which is supported by complex depositional structures. According to the type of glacial depositional features, the glaciers in the study areas were likely to have characteristics of moraine‐dammed glaciers. Due to vertical drainage ice‐marginal fluvial processes were unable to evacuate sediment. Fluvial transport between glacial and pro‐glacial systems in karst areas is inefficient. Nevertheless, some sediment from the glacier margin is washed away by the pro‐glacial streams, filling the karst depressions and forming piedmont‐type poljes. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   

萍-乐坳陷带之岩溶发育规律及岩溶水富集特征     

张爱华 《火山地质与矿产》2010,(2):149-156

萍-乐坳陷带为江西省最主要的隐伏岩溶发育区带之一,岩溶地层发育,地表水、地下水循环交替强烈,地质构造复杂,为岩溶的发育、岩溶地下水的富集提供了良好的条件。查明岩溶发育规律及岩溶水的富集特征,可为地下水资源合理开发与地质环境保护提供科学依据。  相似文献   

Changes in hydrological regime caused by human intervention in karst: the case of the Rumin Springs     

O. Bonacci  N. Buzjak  T. Roje-Bonacci 《水文科学杂志》2013,58(13):2387-2398

ABSTRACT

Any human intervention or action in karst terrains can unexpectedly, suddenly, strongly and, generally, dangerously change a local and/or a regional hydrological regime. A characteristic example of the Dinaric karst is given in this paper. The operation of two reservoirs in Livanjsko Polje at an altitude of about 702 m above sea level (m a.s.l.) and hydro-electric development of the Cetina River system started in 1973. This year marked a drastic and instantaneous change in the regional hydrological regime. A significant drop in the minimum, mean and maximum annual discharges of two neighbouring karst springs, Rumin Mali and Rumin Veliki, was caused by this anthropogenic construction. The exits of the two analysed karst springs, Rumin Mali and Veliki, are located at altitudes of about 326.8 m a.s.l. and 307.6 m a.s.l. respectively. The areal distance between them is 640 m. Their hydrological regimes have been altered in different ways. The drop in discharges is stronger for the Rumin Veliki than for the Rumin Mali. The analysis shows that the system development influenced the redistribution of the regional karst aquifer and, in this manner, contributed to the reduction of both karst springs’ recharge areas.