On April 25, 2015, the Himalayan Mountains experienced a magnitude 7.8 earthquake in Nepal. The earthquake was caused by the Indian tectonic plate continuing to push into the Eurasian plate. This continent-to-continent plate collision is ultimately what formed the Himalayan Mountains.
Geologists hypothesize that another earthquake in the region is still imminent. The April 2015 earthquake had its epicenter located 50 miles northwest of Kathmandu. The earthquake released the stress along the fault to the east. The western stretch of the fault did not move, and thus did not release any stress.
This western stretch of the fault spans from Kathmandu to New Deli, a distance of about 500 miles. A major earthquake along this portion of the fault has not occurred since 1505, in which geologists feel could have been a magnitude 8.5 earthquake.
The video below shows a series of landslides caused by aftershocks from the April earthquake that we featured last May.