Reservoir-induced earthquake
Also called: Reservoir-induced seismicity, Induced seismicity · Topic: Natural Hazards and Disaster Management in India · NCERT: Class 10, Ch 3 "Water Resources"; Class 11, Ch 6 "Natural Hazards and Disasters: Causes, Consequences and Management"; Class 11, Ch 3 "Interior of the Earth"
Meaning
A reservoir-induced earthquake is set off by filling a large dam reservoir. The huge weight of water presses down on the crust. Water also seeps into cracks in the rock and raises pore pressure, which is the water pressure inside those cracks. Higher pore pressure makes it easier for the rocks on a fault to slip. A fault already under stress can then give way. This matters when deciding where to build big dams.
Example
The classic case is the Koyna earthquake of 11 December 1967 near the Koyna dam in Maharashtra. Its magnitude was about 6.3.
Don't confuse with
- Latur earthquake 1993: this was also a Peninsular quake in Maharashtra, but it is linked to the Bhima fault, not to a reservoir.
Related concepts
- Himalayan earthquakes
- Seismic zones of India
- Bhima fault
- Latur earthquake 1993
- Bhuj earthquake 2001
- 2005 Kashmir earthquake