Is the Eruption of Mount Soputan Related to Earthquake in Palu?

By Adi Permana

Editor Adi Permana

BANDUNG,itb.ac.id – Mount Soputan, 50 kilometer to the south west of Manado, North Sulawesi, erupted on Wednesday (3/10/2018) at 08.47 Central Indonesian Time with eruption column to be 4 km as reported by PVMBG of Mount Soputan Observation Post.

People began to relate the eruption of this 1809 m above sea level-tall volcano to the earthquakes that hit Palu several days ago. Does earthquake cause volcano eruption?

Volcanologist from Institut Teknologi Bandung (ITB), Dr.Eng.Mirzam Abdurrachman explained that earthquake may trigger eruption. It happened to Mount Agung eruption that occurred minutes after earthquakes hit south of Bali. The same case happen to Mount Fuji in Japan.

However, he also said that earthquake does not cause eruption. Repeated earthquakes that hit Lombok did not increase the activity of Rinjani. “Why? Because it is not the eruption period, yet. Rinjani’s empty magma chamber tolerate the shock so that no eruption happened.”

What about the eruption of Mount Soputan? Previously, the mount erupted in 2012 and 2015, having eruption interval every 3 years. Thus, 2018 is the time of eruption.

However, the eruption could be a combination of both eruption period and the trigger from earthquake. It is seen from the eruption materials, which are mostly ash without magmatic material. That indicates basic pressure change within magma chamber.

“Seismic data record and further observation to eruption products of Mount Soputan in the next few days will provide more definitive answers,” he said