NORTH SUMATRA / RankWire.AI / – On Tuesday, a magnitude 6.1 earthquake struck offshore North Sumatra province, Indonesia, causing tremors felt across various regions of Sumatra. The seismic event occurred at 1:02:23 p.m. western Indonesian time, or 06:02:23 UTC. According to official data, the epicenter was located in the sea, 147 kilometers southeast of South Nias Regency, at a depth of 29 kilometers, originating beneath the waters west of Sumatra.

The Meteorology, Climatology and Geophysics Agency of Indonesia, known as BMKG, pinpointed the quake at 0.65 degrees south latitude and 98.32 degrees east longitude. The strongest recorded shaking was in North Tapanuli, where residents reported an intensity IV. Other parts of West Sumatra also experienced noticeable tremors, affecting communities in Padang, Padang Pariaman, Pariaman, West Pasaman, and Agam.
Across other regions of Sumatra, reports of shaking emerged following the magnitude 6.1 event. The National Disaster Mitigation Agency, or BNPB, confirmed that the quake posed no tsunami threat. In South Nias, residents experienced mild shaking lasting approximately three to five seconds. Local disaster management offices began assessing the impacted areas, while the initial official bulletin did not report any casualties or damage figures.
Officials confirm absence of tsunami risk
Intensity levels reached III to IV in Padang, Padang Pariaman, Pariaman, West Pasaman, and Agam, based on official records. Padang Sidempuan, Subulussalam, and South Nias recorded intensity III, while Padang Panjang and Central Tapanuli saw intensity II to III. Gunungsitoli registered at intensity II. These measurements indicate the earthquake was felt across multiple provinces, though the reported shaking severity varied by location.
Authorities urged the public to stay calm and rely solely on verified earthquake information following the offshore seismic activity. Residents were advised to inspect their homes and structures for cracks or damage, and to move to open spaces if another strong earthquake strikes. Officials also recommended avoiding beaches and coastal areas after significant aftershocks as part of safety precautions issued in response to the event.
Ongoing monitoring continues after offshore seismic event
Official records updated Wednesday confirmed the South Nias earthquake as a magnitude 6.1 event at a depth of 29 kilometers, with the epicenter still located 147 kilometers southeast of South Nias. The latest data did not include a tsunami warning. Disaster response teams remain vigilant, actively monitoring the affected regions to detect any potential impacts from the tremor.
The quake took place on August 18, amid widespread alerts and reports across western Indonesia. Officials continue to guide the public with verified information and safety instructions. Residents are advised to avoid damaged structures and stay alert for further tremors. Confirmed reports continue to identify the event as a magnitude 6.1 offshore earthquake, with no threat of a tsunami.
