Could Bandung's Earthquake Swarm Lead to a Bigger Quake?
Dozens of earthquakes have struck Bandung Regency, West Java. An expert explains what an earthquake swarm means and whether it signals a bigger quake.
A series of earthquakes in Pangalengan, Bandung Regency, West Java, Indonesia, has raised concerns about the potential for a larger earthquake. However, Dr. Daryono, a disaster expert at the Indonesian Association of Disaster Experts (IABI), explained that an earthquake swarm does not necessarily foreshadow a major quake. According to Dr. Daryono, a swarm does not always indicate that earthquakes will continue to increase in frequency or magnitude; some swarms may gradually dissipate.
BMKG data recorded numerous earthquakes in and around Pangalengan since September 16, some felt by residents, with the latest one measuring 2.6 magnitude at 4:59 a.m. local time. This earthquake occurred about 23 kilometers south of Bandung Regency at a depth of 3 kilometers.
An earthquake swarm refers to a series of repeated earthquakes in the same area over time without a dominant mainshock. Dr. Daryono emphasized that swarm activity indicates deformation and stress release in the Earth's crust but can also be linked to various processes, including fault movement or volcanic activity. To accurately assess a swarm, continuous seismological data is necessary rather than solely relying on the number of earthquakes.
Dr. Daryono clarified that an increase in swarm activity does not automatically mean a bigger earthquake is imminent. Some swarms can weaken without leading to a larger event. Pangalengan, situated in southern West Java, lies near the Garsela Fault system, known for its seismic activity in the region. The depth of an earthquake significantly impacts its perceived intensity; shallower earthquakes are more likely to cause noticeable shaking, even if they are of small magnitude.
Residents are advised not to panic but to stay prepared by securing furniture and learning the "drop, cover, and hold on" procedure for earthquakes. Dr. Daryono urged caution against associating every swarm increase with the risk of a major earthquake, emphasizing the importance of remaining alert and following official updates from BMKG. Secondary hazards like landslides may also arise from seismic activity, so continuous monitoring of official information is crucial for residents in the area.
Written by urgent.news from Tempo.co English's reporting — not their text. Machine-written — may contain errors; check the original before relying on it.
