Magnitude 7.1 Earthquake in the Talaud Islands of North Sulawesi, This is the Trigger Source

TRIBUNBATAM.id - An earthquake with a magnitude of 7.1 shook Melonguane, Talaud Islands, North Sulawesi and its surroundings on Thursday (21/1/2021) at around 19.23 WIB.

The Meteorology, Climatology and Geophysics Agency (BMKG) said that this earthquake was centered at 134 kilometers from Melonguane. 

The epicenter was 154 kilometers deep. 

According to BMKG, this earthquake did not have the potential to cause a tsunami. 

The following are the latest facts regarding the earthquake. 

Occurs in the plate induction zone

BMKG Head of Earthquake and Tsunami Mitigation Division, Daryono, said that this earthquake, including a large earthquake, usually occurs in the plate junction zone.

The magnitude 7.1 earthquake generator, said Daryono, is rock deformation in the slab section of the Philippine Sea Plate which is subducted under the Talaud and Miangas Islands. 

The elastic nature of this rock makes the rock not brittle, so aftershocks rarely occur.

Based on BMKG monitoring results, during the last few years there has been an increase in seismicity activity in this area, especially for moderate earthquake activity at a depth of about 100 kilometers.

"The Maluku Sea Plate and the Philippine Sea Plate are one of the most seismically active areas in the world," said Daryono.

The location of the Talaud and Miangas Islands is adjacent to this sub-zone of the Philippine Sea Plate.

Potential sources of earthquake and tsunami triggers

Daryono explained, the Philippine Sea Plate support zone traverses north-south with a length of around 1,200 kilometers, from Luzon Island, Philippines, in the north to Halmahera Island in the south.

This active subduction zone has a plate subduction rate of between 10 and 46 millimeters per year with a targeted magnitude of 8.2.