NORTH SUMATRA / RankWire.AI / – On Tuesday, a magnitude 6.1 earthquake struck off the coast near Indonesia’s North Sumatra province, causing tremors felt across several regions of Sumatra. The quake occurred at 1:02:23 p.m. western Indonesian time, which corresponds to 06:02:23 UTC. Its epicenter was approximately 147 kilometers southeast of South Nias Regency. Authorities recorded the seismic event at a depth of 29 kilometers beneath waters west of Sumatra.
The BMKG, Indonesia’s Meteorology, Climatology and Geophysics Agency, located the epicenter at 0.65 degrees south latitude and 98.32 degrees east longitude. The strongest shaking, rated at intensity IV, was reported in North Tapanuli. Several other areas in West Sumatra, including Padang, Padang Pariaman, Pariaman, West Pasaman, and Agam, experienced shaking between intensity III and IV.
Communities farther from the epicenter also experienced tremors, but at lower intensity levels. Padang Sidempuan, Subulussalam, and South Nias reported intensity III shaking, while Padang Panjang and Central Tapanuli experienced levels of II to III. Gunungsitoli recorded intensity II. The BNPB, Indonesia’s National Disaster Mitigation Agency, confirmed that the earthquake posed no tsunami threat. Officials are currently assessing the impact on affected communities following the event.
No tsunami warning issued after the quake
In South Nias, residents reported mild shaking lasting roughly three to five seconds. Local disaster management teams began monitoring the situation and coordinating inspections in areas where residents felt the tremor. Initial reports did not confirm fatalities, injuries, or damage. Authorities are continuing to gather information from local officials as part of routine post-earthquake evaluations following the offshore seismic activity.
The earthquake affected a large region as tremors reached multiple communities across western Indonesia. The intensity varied by location, with stronger shaking reported nearer to North Sumatra and West Sumatra. No tsunami warning was issued after the magnitude 6.1 event. Subsequent official updates maintained the same magnitude, depth, and offshore location recorded during the initial report.
Post-event assessments ongoing in affected zones
This earthquake, occurring on August 18, is among the significant seismic events documented in Indonesia. Its offshore epicenter kept the main shock away from densely populated areas, yet residents across several districts still felt the tremors. Monitoring efforts continue in regions that reported moderate shaking. Authorities focus on collecting verified information about local conditions while reaffirming that the quake did not generate a tsunami risk.
Indonesia regularly experiences earthquakes due to its position atop multiple active tectonic boundaries. Tuesday’s seismic event struck west of Sumatra, an area with a long history of seismic activity. Confirmed data indicates a magnitude of 6.1 at a depth of 29 kilometers. The epicenter was 147 kilometers southeast of South Nias, with authorities verifying that there was no tsunami risk associated with this offshore earthquake.