A Conceptual hydrodynamic model of a geological discontinuity in hard rock aquifers: Example of a quartz reef in granitic terrain in South India

Publication year: 2011
Source: Journal of Hydrology, In Press, Accepted Manuscript, Available online 13 June 2011

Benoît, Dewandel , Patrick, Lachassagne , Faisal K., Zaidi , Subash, Chandra

The structure and hydrodynamic properties of geological discontinuities and of a deeply weathered granite aquifer near these structures are described on the basis of geological, geophysical and hydrodynamic investigations in two sites of South India located along a 20-40-metre-wide quartz reef intruding a weathered Archean biotite granite. One of the two sites also comprises a metre-wide dolerite dyke.Weathering processes appear to be at the origin of fissures development and of a related enhanced local hydraulic conductivity, both in the quartz reef and in the surrounding granite. The weathering profile in the granite (saprolite and fissured layer) is characterized by an…

 Highlights: ► Hydrodynamic properties of quartz reef in granite are described. ► Weathering processes appear to be at the origin of fissures permeability. ► Results ► complete the conceptual hydrogeological model for hard rock aquifers. ► Method for identifying the heterogeneity in permeability is proposed.