PETALING JAYA: More collaboration in research between Indonesia and Malaysia is needed to understand how Indonesia’s earthquakes would affect Malaysia, said a geologist.
Universiti Teknologi Malaysia Centre of Tropical Geoengineering director Prof Dr Edy Tonnizam Mohamad said Malaysia may experience tremors when the Sunda plate on which it sits collides against the Philippines Sea Plate near Sabah or the Indo-Australian Plate on the west.
“Researchers have mapped out most of the potential fault zones in Malaysia and studied their potential reactivity.
“The nature of earthquakes in Malaysia is different from Indonesia because Indonesia is located near to the subduction zone,” he said.
Prof Edy said that subduction zones are areas where two tectonic plates collide and hit each other.
“What could be improved is our understanding of how the regional subduction patterns, such as the ones in Indonesia, affect our country’s fault lines,” he said in an interview.
Recently, Sulawesi in Indonesia was hit by a 7.5-magnitude earthquake, which triggered a tsunami and left more than 2,000 people dead.
Prof Edy disputed the misconception that quarrying, mining activities and construction of the MRT train line would lead to earthquakes.
“These activities do not penetrate very deep into the ground whereas the earth’s crust is much thicker,” he added.
While there have been earthquakes in Sabah, it is not a well-known fact that earthquakes frequently occur in Peninsular Malaysia as well.
Prof Edy said there are seven main fault lines in Peninsular Malaysia – Bok Bak Fault, Lebir Fault, Terengganu Fault, Bukit Tinggi Fault, Kuala Lumpur Fault, Lepar Fault and Mersing Fault.
He said fault zones are the breakage between plates, likening it to the joints of our body.
“These fault zones are like the ‘joints’, where movement is easier compared to body parts that are solid and rigid.
“Generally, these fault lines in Peninsular Malaysia are stable but there have been low- to medium-scale tremors recorded in a few locations,” he said.
Tremors have been recorded even in places such as Kuala Lumpur, Bukit Tinggi, Jerantut and Baling in the past decade, he said, although these do not exceed 4.0 on the Richter scale.
In Sabah, Lahad Datu experienced a 6.2-magnitude earthquake in 1976 while a 5.9-magnitude earthquake struck Ranau in 2015, leading to 18 deaths.
A spokesman from Institute of Geology Malaysia said earthquakes felt in Malaysia are from two sources.
One is known as the “far-field earthquakes”, which arise from earthquakes originating in Sumatra or the Philippines.
The second source of earthquakes are those of local origin, which are the tremors felt in the Kenyir Dam or in central or eastern Sabah.
He, however, dispelled the notion that the fault lines in the peninsula would be reactivated and leave Malaysia at risk of large-scale tremors.
“There is currently no evidence to show there would be reactivation of fault lines in Peninsular Malaysia.
“In Sabah, there are active fault zones in the Ranau and Lahad Datu areas and these are also being monitored by the Department of Mineral and Geoscience Malaysia and the Malaysia Meteorological Department,” he said, adding that active measures are being taken by the authorities to prepare for earthquakes.