Voxnusantara.com – The Meteorology, Climatology and Geophysics Agency (BMKG) suspects an earthquake of magnitude (M) 5.0 (Updated M 4.9), which has just rocked the West Sulawesi region (Sulbar), Sunday (26/08/21) at 17:32 WITA, yesterday afternoon it was caused by the activity of the Naik Mamuju or Mamuju Thrust fault.
“This type of earthquake is a type of shallow crustal earthquake, it is strongly suspected that it was triggered by the Mamuju Thrust fault activity with an upward movement mechanism (Thrust Fault),” Head of the BMKG Earthquake and Tsunami Mitigation Division, Daryono.
Furthermore, Daryono said, the existence of the Mamuju Thrust fault has certainly been the cause of many significant and destructive earthquake activities in the West Sulawesi region. Including, he said, the cause of the earthquake on January 15-16, 2021, which was centered in Majene.
“The Mamuju Thrust Fault caused a lot of earthquake activity, such as what happened on December 23, 1915, April 11, 1967 (M 6.3), February 23, 1969 (M 6.9), September 6, 1972 (M 5.8), January 8 1984 (M 6.7), November 7, 2020 (M 5.3) and January 15-16, 2021,” he explained.
If we record history, said Daryono, this fault has caused 3 (three) tsunamis on the west coast, West Sulawesi, namely on January 8, 1984 (M 6.7), April 11, 1967 (M 6.3) and February 23, 1969. (M 6.9). “The West Sulawesi region is indeed known as an active and complex seismic area, because there are fold and thrust belts off the coast and coastal areas,” he explained.
So, he said, regarding the M 5.0 earthquake that just happened, it was difficult to predict whether it was a preliminary earthquake (Foreshock) or not, because of the unpredictable strong earthquake activity, he admitted.
“The M 5.0 earthquake has not caused a single aftershock (Aftershock) at least until 20:43 WITA. However, I ask the public and government agencies to continue to make mitigation efforts, in order to reduce the risk of disasters that occur in the future. come,” he pleaded.***