Weather bureau chief downplays volcanic magma chamber concerns

Taipei--The magma chamber recently confirmed to exist in the Datun Volcano Group in northern Taiwan is not evidence that the volcano group has become active, the head of Central Weather Bureau said Tuesday, rebutting a newspaper report.

The local newspaper Apple Daily reported Tuesday that the Datun Volcano Group, which has long been seen as a group of dormant volcanoes, has been confirmed to be active after a study concluded at the end of 2016 that a magma chamber exists 20 kilometers beneath the Jinshan and Wanli districts in New Taipei.

The report said that if a volcano in the area were to erupt, it would affect residents in the Yangmingshan area and in Taipei's Shilin and Beitou districts.

Asked about the report, Central Weather Bureau Director-General Shin Tzay-chyn (???) told CNA that the study's conclusions should not be overinterpreted.

The study merely confirmed the existence of the magma chamber in the Datun Volcano Group but did not address whether the magma chamber is moving toward the earth's surface or continuing to cool, Shin said, making it impossible to judge if the volcanoes are active.

If the magma chamber were moving toward the earth's surface, that might be evidence of an active volcano, but the magma chamber would still have to be within five to 10 kilometers of the surface to pose a threat, he said.

The weather bureau has a system to monitor the activity of the Datun Volcano Group, and there has been no sign so far of the magma chamber moving toward the surface, Shin said, urging the public not to panic.

But Lin Cheng-horng (???), the researcher behind the study, said it is hard to predict when a volcano will likely erupt and what its scale might be, and he urged the government to expand its monitoring area in northern Taiwan, the report said.

A magma chamber is a large underground pool of molten rock found beneath the surface of the earth. The molten rock in such a chamber is under great pressure, and if it finds a way to the surface, there will be a volcanic eruption.

Many volcanoes are situated over magma chambers.

Citing historical data, Shin said the most recent Datun volcano eruption occurred about 200,000 years ago. But he acknowledged that another viewpoint has surfaced in recent years that an eruption in the group took place about 5,000 years ago.

If that argument is accurate, the magma chamber found in the recent study, which was conducted over more than a decade, could likely be a cooling magma chamber following the eruption 5,000 years ago, he said.

Source: Focus Taiwan News Channel