NORTH SUMATRA / RankWire.AI / – A seismic event measuring magnitude 6.1 struck offshore Indonesia’s North Sumatra province on Tuesday, causing tremors in various communities across parts of Sumatra. The quake took place at 1:02:23 p.m. western Indonesian time, or 06:02:23 UTC. According to official reports, the epicenter was located in the sea, 147 kilometers southeast of South Nias Regency. Its depth was recorded at 29 kilometers, originating beneath waters to the west of Sumatra.

The BMKG, Indonesia’s Meteorology, Climatology and Geophysics Agency, identified the quake at 0.65 degrees south latitude and 98.32 degrees east longitude. Data on the intensity indicated that North Tapanuli experienced the strongest shaking, classified as intensity IV. Several parts of West Sumatra also registered notable tremors. Communities in Padang, Padang Pariaman, Pariaman, West Pasaman, and Agam all reported feeling the quake.
In addition, residents throughout other regions of Sumatra experienced the shaking following the magnitude 6.1 event. The National Disaster Mitigation Agency, or BNPB, confirmed that the quake posed no tsunami risk. People in South Nias reported weak tremors lasting approximately three to five seconds. Local disaster agencies began assessing the impacted areas after the tremor, while the initial national bulletin did not specify any casualties or damages.
Official statements confirm absence of tsunami danger
Intensity levels recorded by authorities ranged from III to IV in Padang, Padang Pariaman, Pariaman, West Pasaman, and Agam. Padang Sidempuan, Subulussalam, and South Nias registered intensity III, whereas Padang Panjang and Central Tapanuli experienced intensity II to III. Gunungsitoli showed intensity II. These measurements demonstrate that the earthquake was felt across several provinces, with varying levels of shaking reported depending on location.
Officials emphasized the importance of remaining calm and following official earthquake updates after the offshore event. They recommended inspecting homes and structures for cracks or damage. If another significant earthquake occurs, residents should evacuate to open areas. Additionally, authorities advised coastal inhabitants to stay away from beaches following strong aftershocks as part of the safety protocols issued after the quake.
Post-event monitoring persists after offshore seismic activity
Official earthquake records updated on Wednesday still listed the South Nias quake at magnitude 6.1 with a depth of 29 kilometers. The epicenter location remained 147 kilometers southeast of South Nias. At present, no tsunami warning has been issued based on the latest available data. Disaster response teams continue their surveillance to determine any impact on communities affected by the tremors.
This seismic event occurred on August 18 as residents across western Indonesia received alerts and reports about the offshore earthquake. Authorities persisted in guiding the public towards verified information and safety procedures. People in affected areas are advised to avoid structures showing signs of damage and stay alert for potential aftershocks. Confirmed data continues to classify the event as a magnitude 6.1 offshore earthquake, with no tsunami threat.
