With a magnitude of 7.8, the April 25 earthquake in Nepal was one of the most powerful to strike the region in 80 years. A recent aftershock measuring 7.3 caused further destruction, but how do the strengths of these quakes really compare?
Scales used to measure the magnitude of earthquakes are logarithmic, meaning a whole number increase in magnitude represents a 10-fold jump in measured amplitude. The total energy released* from an earthquake increases even more rapidly with magnitude and gives a clearer indication of its power.
Epicentre depth
The chart below shows every quake of magnitude 5 and above to strike Nepal and the nearby Himalayas** in the last century.
The 1934 and 2015 quakes were both at shallow depths, making them all the more destructive. Their strength also dwarfs the others even though some are reasonably close in terms of magnitude.
Click to see the amount of energy released by the quakes.
* Based on the Kelly Kiloton Index           ** Includes surrounding areas of India and China