Galeras tragedy

The scientists were at Galeras to collect data about its gas levels. They were attending a conference in Pasto organized by the United Nations to gather geologists to study Galeras in order to assess its potential threat to nearby population. Past research had determined that Galeras would probably erupt, possibly endangering Pasto's population of approximately 300,000 people and another 400,000 living in the vicinity of the volcano.[1]

A sign posted at the site.

Memorial bench commemorating Geoff Brown, a victim of the Galeras volcano tragedy, at Beacon Hill, Charnwood, Leicestershire

At the time of the eruption, most predictions were made similarly to the one before the 1980 eruption of Mount St. Helens - that a volcano would erupt, but not specifying an exact time. C. Dan Miller of the United States Geological Survey remarked:[2]

We're able to do a much better job of monitoring the changes that occur at volcanoes as they wake up, but we are still quite a long ways from being able to forecast the time, the magnitude and the character of an eruption.

Since the disaster, research has improved scientists' ability to predict volcanic eruptions. Still, there is not a definite method of prediction. Though scientists were able to make accurate eruptions by employing long-period earthquakes, short bursts of seismic energy, to predict the 1990 eruption of Mount Redoubt in Alaska, these events are known to occur at volcanoes that do not erupt as well. In early October 2004, for example, long-period events took place at Mount St. Helens, only to precede insignificant events.[2]