SPATIAL POSITIONING OF FRACTURE IN HARD ROCK

Fractures in hard rocks are the sites for groundwater occurrence. Most of these fractures are buried with weathered product of rock and difficult to delineate their spatial position. The present study has been carried out with aim to trace fractures associated in quartzite in Navadih village of Dhanbad district. Linear pattern of drainage on satellite imagery and toposheet has been noticed as primary geo-indicator of fractures in the area under investigation. The trend of fracture is NW to SE direction. About 500 m length of fracture measured on satellite image was taken for investigation .Electrical Resistivity Image reveals that fracture is 100 m wide and depth is variable. ERI indicates that depth is about 25 m in the N W side which increase toward SE side. The sub surface set up of fracture has been scanned up to 75 m below ground in SE side .3D special model has indicated that the fracture in vertical in nature but inclined toward SE side in sub surface. Variation of depth of fracture may be due to presence of quartz reef that occurs across in NW side.