Volcanologists at the University of Mexico released a bulletin (Spanish) this morning; here is the Google Translate version. Click the link in the top menu for more information about Popocatépetl as well as updates.
11:00 hs. September 29, 2018
Ramón Espinasa Pereña
Ana Lillian Martín del Pozo
IN INCREMENT, THE POPOCATÉPETL VOLCANO ACTIVITY
• Exhalations and vulcano-tectonic earthquakes have been increasing, because a significant amount of magma is rising, said Ramón Espinasa, from the Cenapred
• The Geophysics Institute placed well seismographs to monitor the activity and predict a major eruption
• Don Goyo has not gone to sleep since December 1994 and the tremor of September 19 of last year, whose epicenter was in a relatively nearby area, affected him, said Ana Lillian Martín del Pozzo, of IGf
The Popocatépetl volcano presents a lot of activity, and is increasing; An example of this is the increase in volcano-tectonic exhalations and earthquakes, the latter of an order of magnitude greater than that seen in the last 24 years.
This data indicates that a significant amount of magma is rising and “within months, a year or the day after tomorrow”, could present an even more important activity than it had, said Ramón Espinasa Pereña, deputy director of Volcanic Risks at the UNAM. the Research Directorate of the National Center for Disaster Prevention (Cenapred).
In this regard, Ana Lillian Martín del Pozzo, specialist of the Institute of Geophysics (IGf) of the University, said that Don Goyo has not stopped: “he is awake since December 1994, he has not gone to sleep, but the tremor of 19 September of last year, whose epicenter was in a relatively close area, affected it. ”
Its dynamism has been registered for a month, and showed a high point on Thursday, September 20, and yesterday saw another important issue column, he explained. The vulcanologist recalled that last Sunday a group of geologists went to collect samples of ash to analyze and determine what is happening.
The ejected ash particles are pulverized rock. “Sometimes magma drops appear and we think they are associated with domes that seem to be smaller, they form when the magma rises and they are pulverized, and they have presented themselves in a chain. One is created and explodes, then another, and explodes, but we must be careful and pay attention to know if there are changes “. This is a volcanic activity different from what has been presented in other periods.
These explosions indicate that the volcanoes are changing, the magma is accommodating, and now we know that magma has risen due to these small explosions, and that its magnitude is relative.
The Popocatépetl and the earthquakes
When talking about the “Effects of the September earthquakes in Popocatépetl”, Espinasa Pereña explained that the current situation of the colossus was going to occur, even without tremors. “If the system was already unbalancing, and there is also a telluric movement, the process will probably accelerate.
In the Memorial Day of the 1985 and 2017 earthquakes, organized by the Institute of Geology (IGL), he clarified that there are many volcanoes that have had large eruptions without being preceded by a tectonic earthquake. However, since the Popo erupted several major tremors have been recorded.
The expert explained that in 2015 Don Goyo had an average of 16.5 monthly volcano-tectonic earthquakes; in 2016 that number increased to 35; in 2017, before September, the average was 39, “but it was already increasing”. From that month until December of last year, it rose to 110, and in January 2018 “the record was broken with 221, and although it has decreased since February, we are still above base levels, with 87”.
The day after the earthquake of September 19, the Popocatépetl had the maximum of exhalations that have been had in a single day, with 286, although that number began to increase much earlier.
The good news is that it is feasible to predict a larger eruption from monitoring data with a well-functioning network thanks to a project with the Geophysics Institute, station relay and well seismometer placement, instead of surface seismographs . Currently, six stations are operating in the cone of the volcano and another four will be placed in the coming weeks, below.
Finally, Martín del Pozzore recommended “respect the Popocatepetl Volcanic Warning Light in yellow phase 2, and be attentive. The population must know that activity can increase and that we must act in accordance with the measures dictated by specialized agencies such as the National Center for Disaster Prevention.
Update, October 5, 2018: Yes, an update on the update. This seemed the best place to link to a technical article I just found about the November 23, 2017, eruption, the largest one that Popo had had at that point since 2013.
Featured image: Emilion Pin, via Wikimedia, CC BY-SA 3.0.