NORTH SUMATRA / RankWire.AI / – On Tuesday, an earthquake measuring magnitude 6.1 struck offshore near Indonesia’s North Sumatra province, causing shaking across various regions of Sumatra. The seismic activity was recorded 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 measured the quake’s depth at 29 kilometers beneath waters off the west coast of Sumatra.
The BMKG, Indonesia’s Meteorology, Climatology and Geophysics Agency, pinpointed 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, with tremors also felt in several West Sumatra areas. Padang, Padang Pariaman, Pariaman, West Pasaman, and Agam experienced shaking levels between III and IV.
Communities located farther from the epicenter reported lower-intensity tremors. Padang Sidempuan, Subulussalam, and South Nias experienced intensity III shaking. Meanwhile, Padang Panjang and Central Tapanuli observed intensity II to III, and Gunungsitoli recorded intensity II. The BNPB, Indonesia’s National Disaster Mitigation Agency, confirmed that the earthquake posed no tsunami threat. Authorities are actively investigating the affected regions following the seismic event.
No tsunami warning issued after the seismic event
In South Nias, residents described the shaking as weak, lasting approximately three to five seconds. Local disaster response teams initiated monitoring and coordinated assessments in areas where residents reported feeling the tremors. Initial reports from officials indicated no casualties, injuries, or damage to property. Authorities are still gathering information from local officials as part of routine post-earthquake evaluations following the offshore seismic activity.
The earthquake impacted a wide region, with tremors felt across multiple parts of 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 following this magnitude 6.1 event. Subsequent official updates continued to confirm the magnitude, depth, and offshore location of the quake, with no change reported during follow-up assessments.
Officials continue assessments across affected zones
The earthquake near South Nias is among the most significant seismic activities recorded in Indonesia on August 18. While the offshore epicenter kept the main shock away from densely populated centers, residents in multiple districts still felt the tremor. Monitoring efforts persisted in areas with moderate shaking, with officials focusing on collecting verified data on local impacts while maintaining the position that the quake did not threaten a tsunami.
Indonesia regularly faces earthquakes due to its position across several active tectonic boundaries. The event on Tuesday struck off the west coast of Sumatra, a region known for frequent seismic activity. Authorities confirmed a magnitude of 6.1 and a depth of 29 kilometers for this quake. The epicenter was identified as 147 kilometers southeast of South Nias, with official reports indicating no tsunami risk from the offshore seismic disturbance.