Geophysical study to characterize input karst water circulation in the saulges cave (Mayenne, France)

Abstract Understanding of the recharge origin, runoff channels, and discharge characteristics of karst groundwater is very important for construction of underground projects and identification of water supply targets. Complex structural systems, lithological differences, and extreme heterogeneity of aquifers combine to create a complex karst aquifer structure in alpine and gorge areas; however, because of the topography, direct investigation of aquifer structure is difficult. In this study, field survey, hydrochemical, and isotopic data are analyzed to reveal the development of karst groundwater and to describe the karst water cycle in Genie Mountain, Qinghai–Xizang Plateau. The results show that atmospheric precipitation and melting ice and snow are the groundwater recharge sources, and groundwater circulation is shallow, with groundwater ages generally no more than 60 yr. The groundwater cycle can be divided into three levels: epikarst water circulation; mid to deep karst water circulation; and deep geothermal water circulation. The karst springs located in the outlet of the Huolong gully contain markedly higher levels of Na + and SO 4 2 − than other karst springs because of the leaching effect of groundwater on mirabilite. The presence of evaporites also indicates that the groundwater of Huolong gully is influenced by evaporation. The runoff of thermal springs undergoes deep circulation and is controlled by faults. This water mainly dissolves carbonate rock, with little influence of evaporation. This study shows that hydrochemical and isotopic methods can be used to discriminate different water types, and can be applied to study the characteristics of complex groundwater runoff in alpine and gorge areas.

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Water mixing processes within a crystalline massif: Sudety mountains, SW Poland

Hydrology Research ◽

10.2166/nh.2009.025 ◽

2009 ◽

Vol 40 (1) ◽

pp. 53-64 ◽

Cited By ~ 2

Author(s):

Bartłomiej Rzonca ◽

Sebastian Buczyński

Keyword(s):

Carbonate Rocks ◽

Drainage Basin ◽

Water Circulation ◽

Crystalline Schist ◽

Primary System ◽

Mountainous Area ◽

Karst Water ◽

Mixing Processes ◽

Stream Discharge ◽

Sw Poland

We present the results of a water circulation study in a small drainage basin in a mountainous area of a complicated structure. Two types of waters were found in the basin; the sulphate waters were linked to gneiss and crystalline schist rocks, while the bicarbonate waters were linked to a marble interbed. The paper looks at a number of water circulation and mixing scenarios and discusses the origin of the bicarbonate waters. Measurements and calculations helped to identify two karst water circulation systems within the marble interbed that were probably not connected to each other. The primary system collects waters migrating via fissures from a non-carbonate section of the drainage basin above. Initially these waters are of the sulphate type: acidic and corrosive to the carbonate rocks. After passing into the marble interbed, they gradually assume a bicarbonate nature by becoming saturated with products of the chemical dissolution of carbonate rocks. This karst system is drained by springs. The other system begins in a sinkhole that intercepts a portion of the stream discharge (or all of it during extreme droughts) and ends with dispersed outflows directly into the channel lower down in the drainage basin.

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