Jean-Christophe Maréchal Hydrogeologist Karst Fractured

Six questions, investigated across several observatories and scales, progressively reveal the functioning of fractured basement aquifers.

1. Active zone
Where is the aquifer?
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2. Hydrodynamic properties
How does water flow?
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3. Recharge
How does water enter?
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4. Surface-water interactions
How does the aquifer exchange water with rivers?

5. Local–regional flows
How connected is the system?

6. Critical zone
How does the system evolve?

The resulting conceptual model combines:

a weathered porous layer;
a highly transmissive fractured layer;
a less permeable crystalline basement;
preferential horizontal and vertical fracture networks;
recharge through the weathered zone;
dynamic horizontal connectivity;
local and regional groundwater flow systems.

Key publications

An Observatory of Groundwater in Crystalline Rock Aquifers Exposed to a changing Environment : Hyderabad, India

Jean-Christophe Marechal, Adrien Selles, Benoit Dewandel, Alexandre Boisson, Jerome Perrin, Shakeel Ahmed

Vadose Zone Journal, vol. 17, 2018 Nov

Determining the vertical evolution of hydrodynamic parameters in weathered and fractured south Indian crystalline-rock aquifers: insights from a study on an instrumented site

Alexandre Boisson, Nicolas Guihéneuf, Jérôme Perrin, Olivier Bour, Benoit Dewandel, Amélie Dausse, Mathieu Viossanges, Shakeel Ahmed, Jean-Christophe Maréchal

Hydrogeology Journal, vol. 23, 2015 Jun, pp. 757--773

Groundwater flows in weathered crystalline rocks: Impact of piezometric variations and depth-dependent fracture connectivity

Nicolas Guihéneuf, Alexandre Boisson, Olivier Bour, Benoit Dewandel, Jerome Perrin, A.mélie Dausse, Matthieu Viossanges, Shandra Chandra, Shakeel Ahmed, Jean-Christophe Maréchal

Journal of Hydrology, vol. 511, 2014, pp. 320-334