Tectonic History of Parts of Bhima Basin and its Influence on Groundwater Conditions in Gulburga District, Karnataka

Abstract

The Southern part of Bhima basin was displaced transversly towards west. The net slip of this fault on the northern part is about 35 km. Second order shears are numerous in the area. Gravity and thrust faults are also observed in the region. Folds of plunging, non-plunging and superposed types are identified. The basin seems to be tilted towards north at 5° or, possibly, the central part of the basin is sunken.

There is a distinct variation in groundwater potentiality between the tectonic and non-tectonic regions of both Archaeans and Bhimas. The water table is invariably shallow along the tectonized zones. The unit area specific capacity of wells in the non-tectonic regions falls below 2.01pm/m/m² while it varies upto 55.01pm/m/m² in the tectonic zones. Seepages and springs are located at a number of places in the tectonic zones and also along the 'nala' courses. Their recorded discharges during the summer period vary from 50 to 200 m³/hr.