A press release from the Center for Volcanology and Geological Disaster Mitigation at the Geological Agency of the ESDM Ministry in Jakarta on Friday said the area around the epicenter was generally composed of pre-tertiary, tertiary, and quarterly aged rocks.
Some of the pre-tertiary and tertiary rocks have experienced weathering, it said.
The rocks of the pre-tertiary and tertiary age that have experienced weathering and sediment deposits are generally decomposed, loose, soft, unconsolidated, and strengthen the effects of tremors, which are prone to earthquake shocks
Meanwhile, based on the position and depth of the epicenter of the earthquake, the incident was caused by active fault activity in the Palu-Koro fault zone which trails northwest and southeast.
The Geological Agency urged people to remain calm and follow the directions and information from the local disaster mitigation agency (BPBD) officers.
"Don`t let yourselves be provoked by irresponsible issues regarding earthquakes and tsunamis," it said.
The main earthquake with a strength of 7.4 SR occurred on Friday at 17.02 WIB with an epicenter at coordinates 119.85 degrees East Longitude and 0.18 degrees South Latitude and a depth of 10 km.
The earthquake began with an initial earthquake and was followed by a series of aftershocks in Donggala, Central Sulawesi Province.
Based on the interim report, the earthquake caused the death of one person, injuries to 10 people, and damage to a building in Sinreja District, Donggala Regency.
Meteorology, Climatology and Geophysical Agency (BMKG) data showed that the tremors from the earthquake were felt in Donggala on the VIII MMI scale (modified Mercalli intensity).
The earthquake had the potential to cause a tsunami, but the tsunami early warning was revoked by BMKG.
The main earthquake with a magnitude of 7.4 on the Richter scale occurred on Friday at 5.02pm Western Indonesian Standard Time (WIB) with an epicenter at coordinates 119.85 degrees Eastern Longitude and 0.18 degrees Southern Latitude and at a depth of 10 km.
The earthquake was preceded by an initial earthquake and was followed by a series of aftershocks in Donggala, Central Sulawesi Province.
Reporting by Kelik Dewanto
Editing by Andi Abdussalam
Reporter: Andi Abdussalam
Editor: Suharto
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