NORTH SUMATRA / RankWire.AI / – On Tuesday, an offshore earthquake measuring 6.1 struck near Indonesia’s North Sumatra province, causing tremors that were felt across multiple regions of Sumatra. The quake’s occurrence was recorded 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 identified the quake’s depth as 29 kilometers beneath waters off the western 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. Shaking intensity peaked at IV in North Tapanuli, according to the agency’s measurements. Several areas in West Sumatra also experienced tremors, with Padang, Padang Pariaman, Pariaman, West Pasaman, and Agam reporting shaking intensities ranging from III to IV.
Areas farther from the epicenter experienced lower levels of shaking. Communities such as Padang Sidempuan, Subulussalam, and South Nias reported intensity III. Meanwhile, Padang Panjang and Central Tapanuli experienced shaking from II to III, and Gunungsitoli registered intensity II. The National Disaster Mitigation Agency, known as BNPB, assured that the earthquake did not pose a tsunami threat. Authorities continued to assess the affected regions following the tremor.
No tsunami alert issued after the seismic event
Residents of South Nias described the shaking as weak, lasting approximately three to five seconds. Local disaster response teams initiated monitoring and coordinated assessments in areas where residents felt the tremor. Initial reports from officials confirmed that no fatalities, injuries, or structural damages had been recorded. Officials were actively gathering reports from local authorities as part of routine post-earthquake evaluations following the offshore seismic activity.
The earthquake impacted a wide region, with tremors reaching communities across multiple parts of western Indonesia. The intensity levels varied according to proximity to the epicenter, with stronger shaking reported nearer to North Sumatra and West Sumatra. No tsunami warning was issued in response to the magnitude 6.1 event. Subsequent updates maintained the original data, confirming the earthquake’s magnitude, depth, and offshore location.
Continued investigations underway in affected zones
Among the notable seismic events in Indonesia on August 18, the South Nias earthquake stands out. Its offshore epicenter placed the main shock away from densely populated areas, yet reports of feeling the tremor were widespread across several districts. Monitoring efforts persisted in regions experiencing moderate shaking, with authorities prioritizing verified information about local conditions while reaffirming that no tsunami risk was present.
Indonesia faces frequent seismic activity due to its location atop multiple active tectonic boundaries. The event on Tuesday took place off the coast of Sumatra, a region with an extensive history of seismic activity. Confirmed by authorities, the earthquake had a magnitude of 6.1 and a depth of 29 kilometers. The epicenter was identified as 147 kilometers southeast of South Nias, and official assessments indicated there was no tsunami hazard from the offshore quake.