What is in news : Karnataka State Disaster Management Authority (KSDMA) has attributed the repeated tremors experienced in Vijayapura and Kalaburagi districts between September 4 and October 11 to a phenomenon called hydro-seismicity

Details :

• In hydro-seismicity, water from heavy rainfall enters small fractures in rocks and causes pressure within them. It is described as one of the major reasons for earthquake swarms in peninsular India
• Preliminary observations by geologists indicate that micro tremors of the kind seen in the region normally occur during the post-monsoon period after a heavy rainfall
• Within crustal volumes having fracture permeability, a natural increase in hydraulic head is caused by transient increases in stress due to the elevation of the water table in recharge areas of groundwater basins and can be transmitted down to depths of 10-20 km, thereby triggering micro tremors and sounds.These are due to shallow earthquakes that generate high-frequency surface waves. This type of seismic activity is very common and nothing to worry about, since it may not cascade into a large devastating earthquake