PETALING JAYA - In the wake of dozens of tremors in southern Philippines and the Indonesian islands over the past two weeks, the Malaysian Meteorological Department (MetMalaysia) has put Sabah on a tsunami watch.
The department is on alert particularly for earthquake activities in Mindanao and Sulawesi, closely observing the Celebes and Sulu Sea for a possible tsunami that could sweep Sabah's coastline with little or no warning.
A MetMalaysia official told The Star that in the past two weeks, there were at least 24 earthquakes in Indonesia's Sulawesi and Lesser Sunda Islands and the Philippines' Mindanao island, with the magnitude ranging between 4.4 and 6.0 on the Richter scale.
"We are worried that an earthquake could take place in the middle of the sea, resulting in a tsunami which could engulf Sabah's northern or easterly coast towns," the official said.
At 1.30am on Thursday (Oct 11), a 1.2-magnitude earthquake struck Sabah. The quake was detected at a depth of 9km, with its epicentre located 13km north-east of Ranau.
The official said MetMalaysia was working closely with Philippine and Indonesian agencies to monitor seismic movements in the region around the clock.
"If we suspect any tsunami activity, we will issue immediate public warnings to alert residents of the possible danger and activate other emergency protocols," the official said.
Aside from working closely with the Indonesian and Philippine meteorological departments, MetMalaysia will also monitor the tidal gauge placed around Sabah's coast.
Although Sabah is not seated within the Ring of Fire, a belt of seismic activity running around the basin of the Pacific Ocean, it is close enough to the edge of these fault lines and is susceptible to the compression forces from the interaction of three main tectonic plates.
Sabah is actually located on the south-eastern Eurasian Plate which is bordered by the Philippine Plate and the Pacific Plate.
The Philippine Plate and Pacific Plate are moving westwards, colliding with the Eurasian Plate, at the speed of 10cm a year.
The southern part of the Australian Plate is also inching northwards at 7cm per year. It is the most active and unstable plate.
Although Sabah is located 1,000km away from the collision of these plates, it still can feel the compression force.
In June 2015, Ranau was struck by a 6.0-magnitude earthquake.
Eighteen people, including nine Singaporeans, were killed when they were struck by falling rocks on Mount Kinabalu. Some 137 climbers were stranded on the mountain but were later rescued.
The quake struck at a depth of 10km, with its epicentre located 19km from Ranau town and 54km from Kota Kinabalu.
Tremors were also felt on Sabah's coast and as far in as Bandar Seri Begawan in Brunei and Kudat, 190km north of Kota Kinabalu.
In 1966, Ranau was hit by a 5.3- magnitude earthquake, and another 5.2-magnitude tremor in 1991.
On Sept 28, Palu and Donggala, both coastal towns in Sulawesi, were hit by a powerful 7.5-magnitude earthquake, resulting in a tsunami.
The death toll from this earthquake stands at more than 2,000, with 680 people officially still missing.
However, it is feared there could be as many as 5,000 people still buried in the rubble after large swathes of Palu were swept by waves.
The United Nations estimates that some 80,000 people have been displaced by the disaster, with many now living in tents outside their destroyed homes.