Determining fractures and their orientation for preventing in-situ seepage of water in the Poison Lake, Sikkim, India

The water seepage problem in the poison lake was investigated using Geophysical methods for determining subsurface fractures in the lake area. Major focus of this study is to identify and determine the subsurface seepage locations or fractures and their orientation. Electrical resistivity methods, including profiling and Vertical Electrical Sounding (VES), were used to investigate the location of subsurface fracture zones causing water seepage in the poison lake. Furthermore, a numerical analysis (factor analysis) method was used for conformation as well as the depth of fracture zones. Finally, the azimuthal electrical resistivity technique was used to delineate the orientation of the seepage paths. Two subsurface fractures were delineated at the Poison Lake, which might be the prominent water seepage point in the lake. Delineation of subsurface fractures will help in preventing the water losses from the lake by treating the fractures.