What is the seismic swarm in and why is it related to a volcano?

In the last two weeks, a seismic swarm has been registered in Michoacán that according to the National Autonomous University of Mexico (UNAM) could trigger the birth of a volcano. The series of telluric movements have alerted experts due to the way and area in which they have occurred, so they assured that monitoring the region will be important.

A seismic swarm is a telluric phenomenon in which a group of small tremors is produced, some of them imperceptible to people. Although this is not a new or unknown phenomenon, since last May 1st and until Tuesday, June 8th, it has occurred in Michoacán.

In only 39 days, 242 microearthquakes have been registered in the region of Uruapan and the Michoacan-Guanajuato volcanic corridor, which could correspond to more than 6 earthquakes per day. The UNAM reported that of the more than 200 telluric movements that have occurred, six exceeded four degrees on the Richter scale.

But the problem does not end on June 8, because if we add to the 242 micro-earthquakes that occurred between January and April, we would have a total of 305 small tremors in the first six months of the year. In addition, it is important to remember that in January 2020 seismic swarms also occurred in the area.

In the last year and a half, 4,102 earthquakes have been recorded in the region. The seismic swarm in Michoacán should be monitored since it is regularly the precursor event for the birth of a volcano. However, it is important to clarify that other important factors must come together, in addition to a set of micro-earthquakes, to give rise to the birth of a volcano.