Though it was always vulnerable to earthquakes, Nepal didn’t face any massive one in 80 years, and the landlocked impoverished nation was not prepared for this one, a massive 7.8 earthquake.
The earthquake, a shallow one with depth of just 15 Kms, has affected around 8 million people of Nepal, the UN say in its revised estimates. According to some estimates, the shallow and strong quake has hit almost 40% of Nepal and is expected to cost the nation billions of US$ in reconstruction.
The whole of Himalayan range is considered unstable and Nepal lies there. Mount Everest is getting up every year, a centimetre each year. According to the geologists, Indian plate is sliding under Nepal.
The whole Kathmandu was almost flattened in 1934 earthquake. Nepal could have learnt lessons from it and designed buildings in a way to withstand earthquakes. But among the poorest nations of earth, Nepal could not do it.
Poor it was. It remained poor. And with a continued streak of Maoist insurgency that was taken into mainstream in last decade only. The result was – an unplanned growth. Nepal is basically about Kathmandu and Mount Everest – its best known locations. Then, there is tourism circuit of districts like Pokhara and Janakpur. All these are in a quake-sensitive reason.
Over the years, most of Kathmandu and the valley surrounding it have grown in an unorganized way. Most of the buildings do now follow quake-resistant building rules. Most heritage buildings needed retrofitting. Nepal had seven UN heritage sites before this earthquake. Four are completely destroyed in Saturday’s earthquake. Many localities, buildings, temples and structures are completely decimated.
Himalaya was formed when the Indian plate collided with the Eurasian plate. And Himalaya is still rising up. The Indian plate is sliding under the Eurasian plate and whenever a collision happens, it releases enormous amount of energy. It happened in 1934. It happened on April 25. Killing over 10,000 then. Killing scores now and the complete assessment will take time.
Indian plate is sliding northwards at 5 centimetres per year. It is considered a fast enough pace in geological parlance.
The movement of tectonic plates below India and Nepal creates a fault-line that runs all along the Himalayan range – 1400 mile long. And Nepal is on this fault-line.
Enormous energy is released when the earth crust ruptures due to the stress between the plates and it is a continued process.
But we cannot predict its frequency. Some experts say now Nepal should be ready for a big earthquake every five-six decades. But even they are not sure.
After the earthquake, India has slid around 6-7 feet under Nepal, different scientific estimates say. That means over a thousand miles.
Understanding it is tectonic in nature – you want to understand it or you don’t want to. It all depends on people. For those who want to understand the science behind the Saturday’s earthquake, these are few links:
Scientific American – How The Deadly Nepal Earthquake Happened
Discovery News – The Science Behind The Nepal Earthquake
©/IPR: Santosh Chaubey – https://santoshchaubey.wordpress.com/