May 12, 2015 Earthquake: Dolakha, Nepal

Felt (VII) at Hetauda and (VI) at Bharatpur, Biratnagar, Ghorahi, Kathmandu, Kirtipur and Lalitpur. Also felt (VI) at Patna and (V) at Begusarai, Darbhanga, Meerut, Phulwari Sharif, Rangpo and Shiliguri, India. Felt (V) at Bhaluka and (IV) at Dhaka, Maimansingha Daharapara and Rajshahi, Bangladesh. Also felt (IV) at Thimphu, Bhutan. Felt in much of Bangladesh, northern India, central Nepal and parts of Bhutan. Dhulikhet, Kavrepalanchok, Nepal - CDI: 8; Jaynagar, Bihar, India - CDI: 8; Tulsīpur, Dang Deokhuri, Nepal - CDI: 8; Hetauda, Makwanpur, Nepal - CDI: 7; Tribuvannagar, Dang Deokhuri, Nepal - CDI: 7

Tectonic Summary

The May 12, 2015 M 7.3 Nepal earthquake (SE of Zham, China) occurred as the result of thrust faulting on or near the decollément associated with the Main Himalayan Thrust, which defines the interface between the underthrusting India plate and the overriding Eurasia plate to the north. At the location of this earthquake, approximately 80 km to the east-northeast of the Nepalese capital of Kathmandu, the India plate is converging with Eurasia at a rate of 45 mm/yr towards the north-northeast - a fraction of which (~18 mm/yr) is driving the uplift of the Himalayan mountain range. The May 12, 2015 event is the largest aftershock to date of the M 7.8 April 25, 2015 Nepal earthquake - known as the Gorkha earthquake - which was located 150 km to the west, and which ruptured much of the decollément between these two earthquakes.

While commonly plotted as points on maps, earthquakes of this size are more appropriately described as slip over a larger fault area. Events of the size of the May 12, 2015 earthquake are typically about 55x30 km in size (length x width). The April 25, 2015 M 7.8 mainshock had approximate dimensions of ~120x80 km, directed from its hypocenter eastwards, and towards Kathmandu. The May 12, 2015 earthquake is located just beyond the eastern end of that rupture.

(above from reference #13456)

At least 37 people were killed Tuesday after a major earthquake struck Nepal, triggering landslides and toppling buildings less than three weeks after the Himalayan nation was ravaged by its worst quake in decades. Tuesday's magnitude-7.3 earthquake was centered near the Chinese border between Nepal's capital, Kathmandu, and Mt. Everest. It was followed closely by at least five aftershocks measuring from magnitude-5.6 to magnitude-6.3. In neighboring India, at least 16 people were confirmed dead after rooftops or walls collapsed onto them, according to India's Home Ministry. Chinese media reported one death in Tibet. An official with the International Organization for Migration told the Associated Press a number of buildings collapsed in the isolated town of Chautara in central Nepal after the earthquake, killing at least 4 people. (reference #11207)

Tuesday's earthquake killed at least 76 people, injured another 2,700 and caused landslides that blocked roads and slowed the delivery of relief supplies. The quake struck hardest in the foothills of the Himalayas. Most of the 65 people confirmed dead by Wednesday afternoon were in Dolakha district, northeast of Kathmandu, said the district's chief administrator, Prem Lal Lamichane. (reference #11210)

The U.S. relief mission was deployed soon after a magnitude-7.8 quake hit April 25, killing more than 8,200 people. It was followed by another magnitude-7.3 quake on Tuesday that killed 117 people and injured 2,800. (reference #11212)