Translated with the aid of Google Translate (I can read basic Spanish but am not really fluent in it), it says,
Today marks the 20th anniversary of the tragedy at Galeras in Colombia. On January 14, 1993, at 1:43 pm, while a group of scientists and their guides collected gas samples directly in the crater as part of the activities of the International Workshop on the Galeras Volcanic Complex, the volcano erupted. Although this could be regarded as a minor eruption from the volcanological point of view, nine people near the crater perished, including six volcanologists. This infamous event is recognized by many volcanologists in the world, because there one could draw a relationship between eruptive events and previous earthquakes called “tornillos.”
Surviving Galeras is tough to read, not only because of the facts (see below for a quick overview) but also because it is written by a scientist, whose keen power of observation also brings the reader, not always intentionally, into contact with post-trauma issues and the writer’s self-awareness of brain injury.
As Williams describes it, the scientists drove up the road you can see in the above image, parked near the outpost of buildings. Sixteen members of the group descended into the crater, which is really that whole horseshoe-shaped structure, called a somma after the one at Vesuvius. The active cone at Galeras rises out of the crater. The volcanologists (from a variety of local and international backgrounds) didn’t climb the cone but instead walked around its base, studying its gravity and magnetism, taking gas samples at fumaroles, collecting specimens, and so forth.
Three local citizens were there, too, having climbed up via another route to watch the geoscientists in action.
Williams, who led the party, was in frequent communication with the nearby volcano observatory where colleagues were monitoring the volcano with seismograph. There were little screw-shaped signals, called tornillos, on the seismograms, but nothing that was understood, he says, as signifying an uptick in seismic activity that would signal a coming eruption far enough ahead of time, hopefully, for the volcanologists to get out of there safely.
Seemingly without warning, the cone erupted. It was very brief and relatively small, but it devastated those who were still in or near the crater. Some of the bodies were never found.
Emerson said that we learn geology after the earthquake, and the same thing holds true in volcanology. Since the 1993 eruption of Galeras, volcanologists have known that tornillo seismicity indicates a volcano may be on the verge of erupting.
Let’s take a moment and remember:
José Arlés Zapata, of INGEOMINAS, Pasto, Colombia.
Néstor García, of the Universidad Nacional, Manizales, Colombia.
Igor Menyailov, of the Institute of Volcanology, Petropavlovsk, Russia.
Geoff Brown, of the UK’s Open University.
Fernando Cuenca, of INGEOMINAS, Bogotá, Colombia (no image or link found online).
Carlos Trujillo, CESMAG, Pasto, Colombia (no image or link found online).
The three local people (no images or links found online) were:
Efrain Armando Guerrero Zamboni, his son Yovany Alexander Guerrero Benavides, and the son’s friend Henri Vasquez.