Mt. Merapi in Yogyakarta on Friday (11/5) spewed smokes and volcanic ash. The ash erupted has even reached the city of Yogyakarta.
Head of UGM’s Centre for Natural Disaster Studies, Dr. Djati Mardiatno, M.Si, said the eruption this time was phreatic, which is the event of contact between magma and water that causes the smoke to go out through the column up on the peak of the mountain. Even so, the status of the mountain is still named as normal.
“So, there is a contact between water and magma like the case when water is poured onto cooking oil being heated on the stove,” said Djati to reporters after the eruption on Friday (11/5).
Djati assessed the contact between the water and the magma had been caused by new cracks in the craters that made the ground water spill inside the magma. The crack however is a natural process due to the active magma condition of Mt. Merapi. “The case of phreatic eruption of Merapi had occured before,” he said.
The smokes going out from the peak not just brought vapours but also sand and dust. The dust would spread according to the direction of the wind, he said.
He reminded people not to panic and wear masks when volcanic ash was still pouring. “Volcanic ash contain silica that if inhaled and got into the eyes will cause irritation,” he said.
Despite the event, Djati saw that it did not mean there would be bigger eruptions. As long as the activity of the magma did not go out through the peak, a major eruption would not happen.
Djati expected the government through the local Disaster Mitigation Agency to carry out mitigations according to normal procedures, which is to evacuate residents that are likely to get affected, and prevent mountain climbing activities when eruptions still occur.