Hot springs and the volcano in San Miguel de Allende

Published June 27th, 2021

San Miguel is known for its hot springs, however, one of the little known facts is that San Miguel is part of the Campo Volcanico San Miguel de Allende and is due to the remaining volcanic activity that has these waters that reach 40°C. The Palo Huérfano volcano has been inactive for thousands of years and is part of the municipality’s orography.

The San Miguel de Allende volcanic field is formed by four major stratovolcanoes: Palo Huérfano, La Joya, San Pedro and El Zamorano volcanoes and several minor volcanoes.

The Palo Huérfano Volcanic Complex is located south of SAN Miguel de Allende and includes the following structures: Palo Huérfano Volcano and the domes Cerro Colorado, El Pilón and Elvira. The main edifice has a circular base of approximately 12 kilometers and is crowned by a wide horseshoe-shaped crater of approximately 4 kilometers.

“The inactive volcano receives the name of “Palo Huérfano” because on the top of the massif there was the only large tree in the area that, with the passage of time and product of human inconsistency, was slowly burned and was reduced to ashes”.
Ignacio Bahna

The southern region of the State is part of the physiographic province of the “Neovolcanic Axis” or also known as the “Transmexican Volcanic Belt”, which combines a series of geological conditions such as sedimentary lithology, mainly with the presence of extrusive and intrusive igneous basements, where diverse faulting systems are combined, which has favored the ascent of magmatic bodies at shallow depths that, in combination with the underground circulation of water from the aquifers, has led to the formation of the “Eje Neovolcánico” (Neovolcanic Axis). Subway circulation of water from the aquifers in the area has given rise to thermal manifestations as a result of the remaining volcanic activity.

In Guanajuato, 169 thermal springs have been registered, of which 35 correspond to springs with temperatures ranging from 26 to 93º Celsius, and the remaining 134 are thermal wells with temperatures ranging from 25 to 72º Celsius, according to the evaluation of renewable energy resources in the State of Guanajuato carried out by the CFE in 2002.

It is important to emphasize that you should only go with an expert hiking guide because of the complicated terrain.

Resources: http://biblat.unsm.mx/RevistaMexicana “Geology of Palo Huérfano Volcano”.

Photos: TOSMA