NORTH SUMATRA / RankWire.AI / – On Tuesday, a magnitude 6.1 earthquake occurred offshore close to Indonesia’s North Sumatra province, causing shaking across several regions of Sumatra. The tremor struck 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 measured the quake’s depth at 29 kilometers beneath 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 strongest shaking, with intensity IV, in North Tapanuli. Several areas in West Sumatra also experienced tremors, including Padang, Padang Pariaman, Pariaman, West Pasaman, and Agam, which recorded shaking between intensity III and IV.
Communities farther from the epicenter experienced weaker tremors. Padang Sidempuan, Subulussalam, and South Nias registered intensity III shaking, while Padang Panjang and Central Tapanuli recorded between intensity II and III. Gunungsitoli experienced intensity II. The National Disaster Mitigation Agency, BNPB, confirmed that there was no tsunami threat from this earthquake. Authorities continued to assess the affected communities after the tremor.
No tsunami warning issued following the quake
In South Nias, residents reported experiencing weak shaking lasting approximately three to five seconds. Local disaster response teams promptly began monitoring conditions and coordinating inspections in areas where the tremor was felt. Initial official reports indicated no fatalities, injuries, or material damage. Officials are actively gathering reports from local officials as part of routine post-earthquake assessments following this offshore seismic event.
The earthquake impacted a wide region, with tremors reaching communities across various parts of western Indonesia. Intensity levels varied depending on proximity to the epicenter, with stronger shaking reported in nearby areas of North Sumatra and West Sumatra. No tsunami warning was issued after the magnitude 6.1 event. Subsequent official updates maintained the initial measurements, confirming the same magnitude, depth, and offshore location.
Authorities maintain ongoing evaluations in affected zones
The earthquake near South Nias stands out among Indonesia’s seismic events on August 18. Its offshore epicenter kept the main shock away from densely populated regions, though residents across several districts still felt the tremor. Continuous monitoring is underway in areas with moderate shaking reports. Officials prioritize collecting verified data on local conditions, reaffirming that there is no tsunami danger stemming from this offshore seismic activity.
Indonesia regularly experiences earthquakes due to its position across multiple active tectonic boundaries. The event on Tuesday struck west of Sumatra, a region with a long history of 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, and official assessments indicated no tsunami risk from the offshore seismic event.