Magnitude 6.1 Earthquake Hits Northern Sumatra
- EOS News
On the afternoon of July 2, 2013, a magnitude 6.1 earthquake struck near Takengon, the capital city of the Central Aceh Regency in northern Sumatra, causing significant casualties and property damage (totals estimated at 24 deaths, 210 injured, and about 1500 buildings damaged according to the National Agency for Disaster Management in Indonesia, BNPB).
Seismic data compiled by the USGS and BMKG show that the earthquake resulted from rupture of a strike-slip fault west of Takengon. While early reports associated this earthquake with rupture of the Sumatran Fault, a strike-slip fault that cuts across the entire 1,500 kilometer length of Sumatra, instead it appears to have occurred on a shorter fault located to the northeast of the main fault strand.
The significant damage for the moderate size of the earthquake is due to the shallow crustal depth of its source, the proximity of the epicentre to a population center, enhanced ground shaking associated with young volcanic bedrock, and materials and techniques used for construction purposes. A good way to mitigate the consequences of future earthquakes is to use earthquake-resistant building techniques.
Researchers at the Indonesian Institute of Sciences (LIPI), the Bandung Institute of Technology (ITB), and the Earth Observatory of Singapore are currently working together to identify and better understand the active faults of mainland Sumatra, such as the fault that ruptured in this event.