NORTH SUMATRA / RankWire.AI / – On Tuesday, an offshore magnitude 6.1 earthquake struck near Indonesia’s North Sumatra province, causing tremors felt across various regions of Sumatra. The event took place at 1:02:23 p.m. western Indonesian time, which corresponds to 06:02:23 UTC. The earthquake’s epicenter was located approximately 147 kilometers southeast of South Nias Regency. Authorities recorded a depth of 29 kilometers beneath the waters west of Sumatra.

The BMKG, Indonesia’s Meteorology, Climatology and Geophysics Agency, identified the epicenter at 0.65 degrees south latitude and 98.32 degrees east longitude. The agency reported the highest intensity of shaking as IV in North Tapanuli, while several areas in West Sumatra also experienced tremors. Specifically, Padang, Padang Pariaman, Pariaman, West Pasaman and Agam experienced shaking between levels III and IV.
Communities located farther from the epicenter also sensed the quake at lower intensity levels. Padang Sidempuan, Subulussalam, and South Nias recorded intensity III. Meanwhile, Padang Panjang and Central Tapanuli experienced intensity II to III, with Gunungsitoli reporting intensity II. The BNPB, Indonesia’s National Disaster Mitigation Agency, stated that the seismic activity did not pose a tsunami threat. Authorities remain vigilant and are inspecting affected localities following the tremor.
No tsunami warning issued after the seismic event
Residents in South Nias noted that the weak shaking persisted for roughly three to five seconds. Local disaster management teams began ongoing monitoring and coordinated assessments in areas where residents had felt the tremor. Initial reports from officials confirmed no fatalities, injuries, or structural damage. Nonetheless, authorities continue gathering reports from local officials as part of routine post-earthquake evaluations following the offshore seismic disturbance.
The earthquake impacted a wide area, as tremors were felt across multiple communities in western Indonesia. The intensity varied depending on location, with stronger shaking reported nearer to parts of North Sumatra and West Sumatra. No tsunami warning was issued in response to this magnitude 6.1 event. Subsequent updates maintained the same magnitude, depth, and offshore position as initially recorded.
Continued assessment efforts underway in affected zones
This earthquake in South Nias became one of the significant seismic activities recorded in Indonesia on August 18. Its offshore epicenter placed the main shock away from densely populated areas; nevertheless, residents across multiple districts still reported feeling the tremor. Monitoring efforts persist in regions that experienced moderate shaking. Officials are prioritizing the collection of verified information about local conditions, affirming that the earthquake poses no tsunami danger.
Indonesia regularly experiences seismic activity due to its position along numerous active tectonic boundaries. The recent event occurred west of Sumatra, an area with a long history of seismic occurrences. Authorities confirmed the quake’s magnitude as 6.1 with a depth of 29 kilometers. The epicenter was identified as 147 kilometers southeast of South Nias, and official assessments confirmed there was no tsunami threat from this offshore seismic event.