One Day 13 Earthquakes, NTB Rocked 403 Times Throughout September

Earthquake illustration (ANTARA)

MATARAM - The Central Statistics Agency (BPS) reported that 403 earthquake events were recorded in West Nusa Tenggara (NTB) throughout September 2025, which was dominated by earthquakes measuring less than 3 magnitudes and shallow depths below 60 kilometers.

"Of the 403 incidents, there were two earthquakes that were felt in the West Nusa Tenggara region," said Head of the Mataram Geophysics Station, Sumawan, as quoted by ANTARA, Thursday, October 2.

Sumawan detailed that as many as two earthquakes were felt to West Nusa Tenggara on September 24, 2025 at 03.54 WITA.

The 4.8 magnitude earthquake that occurred in Central Sumba, East Nusa Tenggara has a depth of 34 kilometers which is also felt in Bima and Sumbawa cities with a scale of II MMI (Modified Mercalli Intensity).

Then, tectonic earthquakes that occurred in the northeast of Banyuwangi Regency on September 25, 2025, were also felt to the West Nusa Tenggara.

The earthquake that occurred at 17.04 WITA had a magnitude of 5.3 with a depth of 12 kilometers. The earthquake was felt to the city of Mataram, the capital of NTB Province with a scale of II MMI.

The results of the earthquake analysis in West Nusa Tenggara in September 2025, were grouped by the BMKG into four parts, namely earthquakes based on magnitudes, frequency of events, depth of every earthquake incident, and dominance of earthquake sources.

"Based on the frequency graph, the most earthquakes occurred on September 27, 2025, with 31 incidents," said Sumawan.

Furthermore, he added that earthquakes measuring less than 3 magnitudes occurred as many as 336 incidents. Meanwhile, earthquakes with a range of 3 to less than 5 magnitudes were 66 events, and there was only 1 earthquake that was recorded with a magnitude of more than 5.

BMKG recorded that the depth of the earthquake was less than 60 kilometers as much as 303 incidents, then the remaining earthquake was 60 kilometers to below 300 kilometers as many as 100 incidents.

Based on the seismicity conditions of the West Nusa Tenggara region and its surroundings in September 2025, added Sumawan, earthquake activity was dominated in the earthquake source area in the form of Subduction of the Indo-Australian Plate and Flores Back Arc Thrust Segment Sumbawa.

"The public is advised to remain calm and not be influenced by issues that cannot be justified," concluded Sumawan.