Sulawesi quake: Deteriorating Palu-Koro fault amplified quake's jolt

Motorcyclists riding past a washed up boat and debris in Palu on Oct 1, after an earthquake and tsunami hit the area on Sept 28.
Motorcyclists riding past a washed up boat and debris in Palu on Oct 1, after an earthquake and tsunami hit the area on Sept 28.PHOTO: AFP

JAKARTA (THE JAKARTA POST/ASIA NEWS NETWORK) - The Centre of Volcanology and Geological Hazard Mitigation has said the deteriorating Palu-Koro fault had amplified the jolt of the 7.4-magnitude earthquake that hit Donggala regency in Central Sulawesi.

The fault is a fracture in the earth's crust that runs from the Makassar Strait to the northern part of the Boni Gulf in southern Sulawesi. It runs underneath Sulawesi Island.

The fault's shift is believed to have triggered the major earthquake that struck last Friday (Sept 28) .

"The geological map of Central Sulawesi is composed of rocks that are aged between 10,000 and one million years. But it fell into decay, causing the jolts to be stronger," said the institution's head of earthquake mitigation, Dr Sri Hidayati, on Saturday.

Dr Sri, who is involved in compiling the 2017 Indonesia Earthquake Map, said it was an active fault with a motion that ranged between 30mm and 44mm per year.

She added that the agency had sent the map of vulnerable land motion to local governments nationwide.

Dr Sri suggested that local governments utilise the geological maps as a reference point to implement policies regarding land utilisation and spatial development, as well as the construction of earthquake-resistant infrastructures.

 
 

"We are hoping that local governments utilise the (geological) maps as one of the considerations for spatial planning in their respective areas. For instance, if there is an active fault within an area, do not allow the construction of buildings," she stressed.

Indonesia, which sits on the so-called Ring of Fire, is one of the most disaster-prone countries in the world. The 2017 national earthquake map revealed that the number of active faults across the nation has increased from 81 to 295 since 2010.