Indonesian Meteorology, Climatology and Geophysics Agency issues warning of potential powerful earthquakes
The Indonesian Meteorological, Climatological and Geophysical Agency (BMKG) has warned all residents of the Sunda Strait and Mentawai-Siberut region in regards to the potential threat of megathrust earthquakes. These earthquakes are predicted to occur at two critical points, with an estimated magnitude of greater than 8.0.
Megathrust earthquakes are a sort of seismic activity that happens when tectonic plates collide, with one tectonic plate being forced under one other. Predicted megathrust earthquakes could cause large shaking, resulting in significant damage to infrastructure and severe economic impacts.
Read also: What is the powerful earthquake that supposedly occurred in Indonesia?
Warning Context
The BMKG warning to the general public follows a 7.1-magnitude earthquake that struck Japan on August 8, 2024. Concerns about large-magnitude earthquakes are based on a cycle that happens about every few hundred years.
In the Sumatra and Java megathrust zones, earthquakes have a 200- to 250-year cycle. This warning also highlights the potential for a tsunami, which is currently considered a matter of when, not if.
Read also: On the earthquake within the Sunda Strait and Mentawai-Siberut, which is “only a matter of time”
Explanation of the term “A Matter of Time”
It must be clarified, nonetheless, that the phrase “a matter of time” doesn’t mean that a large-magnitude earthquake triggering a tsunami must be expected within the near future.
According to Daryono, director of the Earthquake and Tsunami Center at BMKG, it’s unimaginable to predict the precise time of such an earthquake.
Although it is understood that seismic activity must have occurred earlier within the two major earthquake zones in Indonesia (Sunda Strait and Mentawai-Siberut), predicting its occurrence is beyond current scientific capabilities.
Read also: Map of sources and hazards of the 2017 Indonesian earthquake
Historical Context and Seismic Activity
Drawing from Map of sources and hazards of the 2017 Indonesian earthquakeThe last recorded earthquakes within the Sunda Strait and Mentawai-Siberut segments occurred greater than 200 years ago.
In the years 1699 and 1780, a bit of the Sunda Strait 200 km wide and 280 km long was hit by powerful earthquakes with a magnitude of 8.5 MW (Moment Magnitude).
Meanwhile, the Mentawai-Siberut segment, which is an element of the big Sumatra volcano, measuring 200 km by 200 km, was hit by earthquakes of magnitude 8.7 Mw and eight.9 Mw, respectively, in 1797 and 1833.
