NORTH SUMATRA / RankWire.AI / – On Tuesday, a magnitude 6.1 earthquake struck waters off Indonesia’s North Sumatra province, causing tremors felt across various parts of Sumatra. The seismic event took place 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, approximately 147 kilometers southeast of South Nias Regency. The quake originated at a depth of 29 kilometers beneath the waters west of Sumatra.

The Meteorology, Climatology and Geophysics Agency of Indonesia, known as BMKG, pinpointed the earthquake at 0.65 degrees south latitude and 98.32 degrees east longitude. Data on its intensity indicated the strongest shaking in North Tapanuli, where residents reported experiencing intensity IV. Several regions in West Sumatra, including Padang, Padang Pariaman, Pariaman, West Pasaman, and Agam, also noted noticeable tremors. The seismic activity impacted communities across these areas.
Reports of shaking from other parts of Sumatra emerged after the event. The National Disaster Mitigation Agency, or BNPB, confirmed that the earthquake posed no tsunami threat. In South Nias, residents experienced weak tremors lasting about three to five seconds. Emergency services began assessing the affected zones shortly after the quake, but initial national reports did not include confirmed data on casualties or damages.
No Tsunami Risk Confirmed by Authorities
According to official intensity records, shaking reached levels of III to IV in Padang, Padang Pariaman, Pariaman, West Pasaman, and Agam. Padang Sidempuan, Subulussalam, and South Nias recorded intensity III. Padang Panjang and Central Tapanuli experienced intensity II to III, while Gunungsitoli reported intensity II. The measurements indicate that multiple provinces experienced earthquake sensations, although the intensity levels varied depending on the location.
Authorities urged residents to stay calm and rely solely on official updates regarding the earthquake. They recommended inspecting homes and structures for cracks or damage and advised moving to open spaces if another significant earthquake occurs. Additionally, officials advised those near coastal areas to avoid beaches following strong aftershocks, as part of safety protocols issued after the seismic event.
Post-Event Monitoring Continues
Latest official earthquake records available on Wednesday confirm the South Nias event persisted at magnitude 6.1 with a depth of 29 kilometers. The epicenter location remained 147 kilometers southeast of South Nias, and no tsunami warning was issued based on the latest data. Disaster response teams continue to monitor the affected regions for potential effects stemming from the tremors.
The seismic activity occurred on August 18, as residents across western Indonesia received alerts and updates about the offshore quake. Officials remain focused on providing verified information and safety guidance. Citizens in affected areas are advised to avoid structures showing damage and stay alert for any aftershocks. Confirmed reports continue to identify this event as a magnitude 6.1 offshore earthquake without a tsunami threat.
