Karstification in the Cuddapah sedimentary basin, Southern India: Implications for groundwater resources [Zakrasevanje v sedimentacijskem bazenu Cuddapah, južna Indija: Posledice za zaloge podzemne vode]
Dar F.A.,CSIR - Central Electrochemical Research Institute |
Perrin J.,Indo French Center for Groundwater Research |
Riotte J.,Indo French Cell for Water science IFCWS |
Gebauer H.D.,German Karst and Cave Research Association |
And 2 more authors.
Acta Carsologica | Year: 2011
The Cuddapah sedimentary basin extends over a significant part of the southern part of Andhra Pradesh State, Southern India. Proterozoic carbonate rocks in the basin are constituted by as three main units- the Vempalle dolomite, the Narji and Koilkuntla limestones. These carbonate rocks are of strategic importance for local communities as they provide the main water source for irrigation and domestic use and they are also intensively quarried for cement production and building stones. It is therefore, of primary importance to assess to which extent these carbonate units are karstified so as to provide recommendations for appropriate land and water resource management. The field investigations carried out indicate that these carbonate units are significantly karstified and karstification has been an ongoing process with several phases under variable climatic conditions. As a result, a significant part of aquifer recharge occurs as point-recharge through swallow-holes and groundwater flow is channelized by conduit networks which emerge at karst springs. Karst development was possibly more active during past humid conditions; however karstification is still an ongoing process under the present semi-arid climate especially in the favorable case where karst drains the runoff issued from upstream quartzitic hills. The karstic nature of these carbonate units need to be integrated in future research and development programmes to avoid practices that may lead to unexpected collapses, reservoir leaks, inaccurate groundwater budgeting, etc.
Investigation of recharge dynamics and flow paths in a fractured crystalline aquifer in semi-arid India using borehole logs: implications for managed aquifer recharge [Etude de la dynamique et des écoulements dans un aquifère cristallin fracturé en zone semi-aride (Inde) à partir de données de forage: conséquences pour la recharge artificielle des aquifères] [Investigação da dinâmica e dos caminhos de fluxo de recarga em um aquífero cristalino fraturado no semiárido da Índia usando registros de poços: implicações para gestão da recarga de aquífero] [Investigación de la dinámica de la recarga y de las trayectorias de flujo en un acuífero fracturado cristalino en la India semiárida utilizando los registros de pozo: implicancias para el manejo de la recarga de los acuíferos]
Alazard M.,Indo French Center for Groundwater Research |
Alazard M.,Bureau de Recherches Géologiques et Minières |
Boisson A.,Indo French Center for Groundwater Research |
Boisson A.,Bureau de Recherches Géologiques et Minières |
And 8 more authors.
Hydrogeology Journal | Year: 2016
The recharge flow paths in a typical weathered hard-rock aquifer in a semi-arid area of southern India were investigated in relation to structures associated with a managed aquifer recharge (MAR) scheme. Despite the large number of MAR structures, the mechanisms of recharge in their vicinity are still unclear. The study uses a percolation tank as a tool to identify the input signal of the recharge and uses multiple measurements (piezometric time series, electrical conductivity profiles in boreholes) compared against heat-pulse flowmeter measurements and geochemical data (major ions and stable isotopes) to examine recharge flow paths. The recharge process is a combination of diffuse piston flow and preferential flow paths. Direct vertical percolation appears to be very limited, in contradiction to the conceptual model generally admitted where vertical flow through saprolite is considered as the main recharge process. The horizontal component of the flow leads to a strong geochemical stratification of the water column. The complex recharge pattern, presented in a conceptual model, leads to varied impacts on groundwater quality and availability in both time and space, inducing strong implications for water management, water quality evolution, MAR monitoring and longer-term socio-economic costs. © 2015, Springer-Verlag Berlin Heidelberg.