Magnitude 6.7 Earthquake in Nias Has Potential to be Destructive

A magnitude 6.9 earthquake, later revised to M 6.7, that jolted South Nias has the potential to be devastating. Based on the BMKG report, the strongest earthquake could occur at the current earthquake location with a magnitude of 8.9.

The epicenter
The epicenter (asterisk) of the 6.7 magnitude earthquake in the sea 161 kilometers southeast of South Nias. (BMKG)

ACTNews, SOUTH NIAS – A magnitude 6.9 earthquake – later revised to magnitude 6.7 – rocked South Nias, Monday (3/14/2022) at 04.09 a.m. Western Indonesian Time. The earthquake has the potential to be destructive, but there is no threat of a tsunami.

The earthquake's epicenter was at 0.71 degrees South Latitude and 98.50 degrees East Longitude, or sea 6 kilometers south of Hibala, South Nias, North Sumatra, at a depth of 25 kilometers. The earthquake was a shallow earthquake caused by plate subduction (megathrust).

"The results of the source mechanism analysis show that the earthquake had a thrust-fault mechanism," Head of BMKG Dwikorita said in an online press conference on Monday (3/14/2022).

Dwikorita continued that the earthquake had an intensity scale of IV MMI and was felt in Padang, Siberut, South Nias, and Gunung Sitoli. Then, with an intensity scale of III MMI, in Padang Panjang, Bukittinggi, West Pasaman, Tuapejat, and Pariaman. Meanwhile, it was felt on the MMI II intensity scale in Payakumbuh, Dharmasraya, Kerinci, South Tapanuli, Pesisir Selatan, Batusangkar, Padang Pariaman, and Solok.

"There have previously been 16 earthquakes in the earthquake area based on record on February 10, 1797. The earthquake triggered a tsunami, killing 300 people. Based on a report, the epicenter was close to the current epicenter with a magnitude of 8.5. The last earthquake at that location occurred in 2017," Dwikorita explained.

Dwikorita explained that based on the records of earthquakes that have occurred in the Mentawai Segment, this segment is active because the tremor occurred several times. The magnitude could reach 8.9 in the worst-case scenario if the Mentawai segment moves.

"This is an estimate of the maximum magnitude that can occur based on the calculation of the segment length and the slip rate," he explained.

Separately, Daryono, Coordinator of BMKG Earthquake, and Tsunami Mitigation, stated that a magnitude 6.7 earthquake, shook Siberut Island, Mentawai Islands, and originated in the Megathrust Zone, had the potential to be destructive. Daryono warns that people should be aware of this earthquake.

"We should be aware of this earthquake. It is difficult to predict whether it is an opening earthquake or not," he said on Monday (3/14/2022) on his Twitter account @DaryonoBMKG. []