Smoke but no fire: Earthquake did not birth new volcano in Mexico

“New” Mexican Volcano Caused by the Oaxaca Earthquake? Not Likely.

This week saw a very strong earthquake in an area of southern Mexico – a M7.4 event centered 25 km from Ometepec. It looks like it was a relatively shallow earthquake (~15 km) that was related to thrusting due to the subduction of the Cocos plate under Mexico. Although this earthquake was larger than we might expect in Mexico, it is in a zone of high earthquake hazard, so the earthquake itself was not surprising – remember, subduction zones and earthquakes go hand in hand. The effects of the earthquake on the area have been significant, with over 1000 building collapsed or damaged, but thankfully few lives were lost.

After the earthquake, there has been a flurry of news in Mexico about a supposed “new volcano” that appeared between Huajintepec and Huixtepec municipality of Ometepec. The details are scant, but the mayor of the district claims the new volcano to be “tiny” (but in other articles, he says the “volcano” has been there “for many years”). As usual, there is a lot of misleading coverage, like this story that shows a picture of an undersea vent at NW Rota 1 in the Marianas Islands (with no caption to say so). There is also a lot of speculation in the Mexican media that the “new volcano” might somehow have caused the earthquake or all the aftershocks being felt in the region.


Tip: Geology.com

The author says this is just a case of media hysteria after a disaster. Comments note that the media covered the quake and then linked in the story of the Ometepec geyser eruping, which it had not done in centuries. Those MIGHT have been connected but, as he describes, there is no evidence a new volcano exists and it would be very unlikely were one to surface there since it’s far from active volcanoes in Mexico. There is a language barrier here that I can’t cross but, once again, you must be careful what you read in the media.