The Time
Nash Jenkins
August 7, 2015
Even after the April disaster, the fault line between India and Asia remains strained
Another major earthquake in the Himalayan Mountains may be imminent, according to new research that suggests the 7.8-magnitude quake that devastated Nepal in April failed to release all of the region’s seismic energy.
For over five centuries, seismic tension has been building beneath the Himalayas as India gradually shifts northward into the continent. In recent decades, a segment of the narrowing fault line between the Indian and Eurasian Plates became locked by friction, intensifying the buildup of energy that culminated in the April 25 earthquake.
The good news, scientists say, is that the quake, which left between 8,000 and 9,000 dead in Nepal and its border countries, could have been significantly worse. When the stress finally broke the fault, at an epicenter about 50 miles northwest of Kathmandu, the expense of energy traveled to the east, opening only the fault’s shorter eastern stretch, according to two concurrent studies published Thursday in Nature Geoscience and Science Magazine.
The longer western expanse of the fault, however, remains locked, and researchers say it “calls for special attention.” The stress-strained portion, which runs for nearly 500 miles roughly from Kathmandu to the northwest of New Delhi, has not seen a major seismic event since 1505, when an earthquake believed to have measured 8.5 on the Richter Scale — significantly larger than April’s event — shook the region. The recent studies suggest that some of the energy released in the April earthquake rippled westward, compounding with the pent-up energy along this portion of the fault, possibly “facilitating future ruptures.”
“This is a place that needs attention,” Professor Jean-Philippe Avouac, the seismologist who led both studies, told BBC News. “If we had an earthquake today, it would be a disaster because of the density of the population not just in western Nepal but also in northern India.”
