People sit inside their makeshift shelter on open ground after an earthquake in Kathmandu, Nepal April 26.
(photo credit: REUTERS)
Much of the damage accompanying the weekend’s earthquake and aftershocks in Nepal may have resulted from inadequate infrastructure that plagues the Himalayan nation, geologist Dr. Ariel Heimann said on Sunday.
“The shaking was very strong and took place in populated areas with weak infrastructure, with poor construction that does not meet standards,” explained Heimann, who is the director-general of the Weizmann Institute’s Davidson Institute of Science Education in Rehovot.
A 50 million-year process in the making, the Himalayan Mountain range exists due to a collision between the Indian Plate and the Eurasian plate, on whose boundary Nepal sits.
Around the world, the rate of damage of earthquakes is caused by several factors, including the earthquake’s intensity: The stronger the quake, the stronger the ground vibrations. Distance from the epicenter also plays a key role, as ground vibrations are strong closer to that center, he explained.
While ground infrastructure may increase or decrease the intensity of seismic waves, Kathmandu lies in a valley with infrastructure that likely increases such waves – thereby exacerbating the damage, Heimann said. Building types and construction execution methods also play a key role in damage, as oftentimes people are injured or killed by collapsing structures rather than by earthquakes themselves.
“Therefore, correct design and construction may significantly reduce the damage to life and property as a result of an earthquake,” he said. “Kathmandu, and certainly the villages in the Himalayas are built in a patchwork, without standards, from blocks and bricks, and therefore easily collapsed due to the strong earthquake.”