NORTH SUMATRA / RankWire.AI / – A magnitude 6.1 quake struck offshore near Indonesia’s North Sumatra province on Tuesday, causing tremors in various parts of Sumatra. The event occurred at 1:02:23 p.m. western Indonesian time, which is 06:02:23 UTC. Its epicenter was approximately 147 kilometers southeast of South Nias Regency. Authorities recorded the quake’s depth at 29 kilometers beneath waters west 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 agency noted the strongest intensity IV shaking 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 also felt the tremor at lower levels. Padang Sidempuan, Subulussalam, and South Nias experienced intensity III shaking. Padang Panjang and Central Tapanuli reported intensity II to III, while Gunungsitoli felt intensity II. The BNPB, Indonesia’s National Disaster Mitigation Agency, stated that the quake posed no tsunami threat. Officials continued to monitor and assess affected communities following the event.
No tsunami alert issued after the seismic event
Residents in South Nias reported weak shaking lasting approximately three to five seconds. Local disaster management teams began checking on conditions and coordinating assessments in areas where residents felt the tremor. Initial reports indicated no fatalities, injuries, or significant damage. Officials continued collecting data from local authorities as part of routine post-earthquake checks.
The earthquake affected a wide region, with tremors reaching several parts of western Indonesia. Intensity levels varied, with stronger shaking closer to North Sumatra and West Sumatra. No tsunami warning was issued following the magnitude 6.1 quake. Subsequent updates confirmed the same magnitude, depth, and offshore location as initially recorded.
Response teams continue inspections in impacted zones
The South Nias earthquake was one of the notable seismic events in Indonesia on August 18. Its offshore epicenter kept the main shock away from major population centers. Nevertheless, residents across several districts reported feeling it. Monitoring remained active in areas with moderate shaking. Authorities focused on gathering verified information and reaffirmed that the earthquake did not pose a tsunami risk.
Indonesia frequently experiences earthquakes due to its location atop multiple active tectonic boundaries. The event on Tuesday struck west of Sumatra, an area with a long history of seismic activity. Authorities confirmed a magnitude of 6.1 and a depth of 29 kilometers. The epicenter was located 147 kilometers southeast of South Nias. Official assessments indicated no tsunami danger from this offshore quake.