Shallow M6.1 earthquake hits North Pagai, West Sumatra, Indonesia

A strong and shallow earthquake registered by the USGS as M6.1 hit the island of North Pagai, Mentawai Islands, West Sumatra, Indonesia at 09:27 UTC on February 2, 2019. The agency is reporting a depth of 10 km (6.2 miles). EMSC is reporting M6.0 at a depth of 12 km (7.4 miles), GEOFON M6.0 at a depth of 10 km.

The epicenter was located 103.8 km (64.5 miles) SSW of Tuapejat (population 0), 176.5 km (109.7 miles) WSW of Sungai Penuh (population 95 913) and 214.6 km (148.2 miles) S of Padang (840 352), West Sumatra, Indonesia.

There are about 39 000 people living within 100 km (62 miles).

3 000 people are estimated to have felt strong shaking, 14 000 moderate, 169 000 light and 40 415 000 weak.

The quake had no tsunami potential, BNPB said. Shaking was felt for about 3 – 4 seconds. 

The quake was preceded by M4.9 at 19:16 UTC on February 1 and M5.4 at 09:03 UTC on February 2, and followed by M5.3 at 09:58 UTC on February 2.

The USGS issued a green alert for shaking-related fatalities and economic losses. There is a low likelihood of casualties and damage.

Overall, the population in this region resides in structures that are resistant to earthquake shaking, though vulnerable structures exist. The predominant vulnerable building types are unreinforced brick with concrete floor and precast concrete frame with wall construction.

Recent earthquakes in this area have caused secondary hazards such as landslides that might have contributed to losses.

Estimated population exposure to earthquake shaking

Selected cities exposed

Regional seismicity

Featured image credit: Google, EMSC, TW/SAM