NORTH SUMATRA / RankWire.AI / – On Tuesday, an offshore earthquake measuring 6.1 in magnitude impacted the waters near Indonesia’s North Sumatra province, resulting in tremors felt across multiple regions of Sumatra. The seismic event occurred at 1:02:23 p.m. western Indonesian time, which corresponds to 06:02:23 UTC. Its epicenter was located approximately 147 kilometers southeast of South Nias Regency. Authorities recorded the quake at a depth of 29 kilometers beneath the waters west of Sumatra.
According to Indonesia’s Meteorology, Climatology and Geophysics Agency, BMKG, the epicenter was situated at 0.65 degrees south latitude and 98.32 degrees east longitude. The agency reported the most intense shaking at level IV in North Tapanuli. Several other areas in West Sumatra, including Padang, Padang Pariaman, Pariaman, West Pasaman, and Agam, experienced shaking levels between III and IV.
Communities farther from the epicenter also detected the tremors at lesser intensities. Intensity III shaking was felt in Padang Sidempuan, Subulussalam, and South Nias. Meanwhile, Padang Panjang and Central Tapanuli experienced intensity II to III, with Gunungsitoli reporting intensity II. The National Disaster Mitigation Agency, BNPB, stated that the earthquake did not pose a tsunami threat. Officials continued assessments in affected communities following the seismic activity.
No tsunami warning following the earthquake
In South Nias, residents reported mild shaking lasting approximately three to five seconds. Local disaster response teams began monitoring the situation and coordinating inspections in areas where the tremors were felt. Initial reports from officials did not confirm any fatalities, injuries, or structural damages. Authorities are still collecting reports from local officials as part of routine post-earthquake evaluations following this offshore seismic event.
The earthquake affected a wide region, with tremors reaching communities across different parts of western Indonesia. The intensity varied by location, with stronger shaking recorded near parts of North Sumatra and West Sumatra. No tsunami warning was issued after this magnitude 6.1 event. Subsequent updates from official earthquake records maintained the same magnitude, depth, and offshore location information, confirming the initial assessment.
Post-event investigations underway across impacted zones
The earthquake near South Nias became one of the notable seismic occurrences in Indonesia on August 18. Its offshore epicenter placed the primary shock away from densely populated areas, although residents across several districts still reported feeling the tremor. Monitoring efforts continued in regions that experienced moderate shaking, with officials prioritizing the collection of verified information about local conditions while reaffirming that the earthquake posed no tsunami danger.
Indonesia frequently experiences seismic events due to its position across multiple active tectonic boundaries. The seismic activity on Tuesday struck west of Sumatra, an area with a long history of earthquakes. Authorities confirmed a magnitude of 6.1 and a depth of 29 kilometers for this event. The epicenter was identified as 147 kilometers southeast of South Nias, and official assessments affirmed that no tsunami risk was associated with the offshore earthquake.