NTT Disaster Similar to 1992 Earthquake, Expert Reveals Cause
A 7.7 magnitude earthquake struck Flores Island, East Nusa Tenggara (NTT), on Saturday (15/8/2026) at 04.58 WIB. The quake, centred 30 kilometres northeast of Nagekeo, triggered a tsunami warning that remained in place until 07.30 WIB.
The characteristics of this earthquake are similar to a comparable event in 1992, with the two epicentres less than 40 km apart. This was revealed by Irwan Meilano, Professor at the Faculty of Earth Sciences and Technology, Bandung Institute of Technology (FITB ITB).
“If we look at the earthquake mechanism and location, this earthquake is very close to and bears similarities with the 1992 Flores earthquake. At that time the magnitude reached 7.9 and was followed by a very high tsunami,” Irwan said via the ITB website.
Irwan noted that the height of the 1992 tsunami was influenced by an underwater landslide that occurred after the earthquake. “Why? Because it was followed by an underwater landslide, so the tsunami was high,” he said.
The 1992 Flores earthquake and tsunami, according to the National Disaster Management Agency (BNPB), claimed up to 2,500 lives.
Irwan expressed hope that similar conditions would not occur in this latest earthquake, despite its similar magnitude and location to the 1992 event. Tsunami trigger factors also need attention.
Although the tsunami warning has been lifted, aftershock activity still requires monitoring. Based on BMKG observations, dozens of aftershocks have been recorded following the main earthquake, with magnitudes reaching up to 6.2.
“Hopefully in this earthquake, although the magnitude is similar — previously 7.9, now 7.7 — and the location is close, less than 40 kilometres away, it is not followed by an underwater landslide, so the tsunami is not as high as the 1992 tsunami,” Irwan explained.
NTT has a history of major earthquakes, including a magnitude 6.6 quake in 2009 and a series of earthquakes north of Lombok in 2018. The Flores Back Arc, an active thrust fault in the Nusa Tenggara sea area, is believed to be the cause of major earthquakes in NTT.
“If we recall 2018, for example, north of Lombok, there was a major earthquake rupture above magnitude six,” Irwan said.
“Learning from the 2018 earthquake, vigilance must not diminish. It is very possible, though we do not hope for it, that this earthquake could trigger adjacent fault segments. This has happened before during the 2018 earthquakes in the Lombok region,” Irwan added.
Irwan also cautioned that aftershocks above magnitude 6 have the potential to cause significant impacts. The earthquake expert urged local residents to remain calm, follow official information from BMKG, and avoid buildings that have sustained cracks or damage.
“There may be many earthquakes, but over time they will diminish. However, there is still a possibility, albeit small, that if an earthquake above magnitude six occurs, it could cause quite significant damaging impacts,” Irwan said.