Thestructureandthehydrodynamicpropertiesoftheweatheringprofileofagraniticarea (53km2Maheshwaramcatchment,stateofAndhraPradesh,India)werecharacterizedindetail andmappedfromobservationsonoutcrops,80verticalelectricsoundingsandlithologsfrom45 borewellsinwhichflowmetermeasurementsandinjectiontestswerealsoperformedtocharacterizethehydraulicconductivitiesoftheconductivefissurezones.