Calderas and Ignimbrites of the Central Sector of the Mexican Volcanic Belt

1. Introduction
2. Caldera types classification
3. The Mexican Volcanic Belt
4. Regional stratigraphy and tectonics of the central sector of the MVB
5. The Amazcala caldera
6. The Amealco caldera
7. The Los Agustinos caldera
8. The Apaseo caldera
9. The Donguinyó-Huichapan caldera complex
10. The Santa María Macua caldera
11. The Los Azufres caldera
12. The La Muerta caldera
13. The San Pedro El Alto caldera
14. The Catedral caldera
15. Volcano-tectonic and geochemical implications.
16. Economic benefits

Gerardo Aguirre's main scientific interests are three, 1) physical and chemical processes in volcanology, 2) origin and development of collapse calderas and related ignimbrites, and 3) relationships between volcanism/magmatism and tectonics. He has focused his research on the study of collapse calderas and associated ignimbrites, but has worked as well in other volcanic features, such as monogenetic volcanic fields, rhyolitic lava domes, and stratovolcanoes. For the past 5 years, he has been actively working on collapse calderas, not only in Mexico, but in other countries too, such as Las Cañadas at Spain, Aguascalientes and Caviahue at Argentina, and Cañas Dulces and Miravalles at Costa Rica. He is a geologist, and his main contributions include volcanic stratigraphy and geologic mapping of volcanic centers, particularly of calderas, from which he builds the geologic or volcanic evolution of them, documenting this basic geologic research with geochronologic, petrographic, and geochemical data, obtained by him or from other colleagues that collaborate with him. Therefore, he favors the idea that geologic and stratigraphic information is the basis for more elaborated studies, such as petrology and modeling; by modeling, he means petrogenesis and physical analogue experiments, and models obtained from numeric methods. For the past 28 years he has worked in the two main volcanic provinces of Mexico, the mid-Tertiary Sierra Madre Occidental and the Miocene-Quaternary Mexican Volcanic Belt. The former includes the largest continuous ignimbrite province of the World, and the origin for this large ignimbrite volume has been a matter of debate in terms of both petrogenesis and deficit of observed vents; there are quite few calderas recognized for the about 460,000 km3 of silicic ignimbrites. In 2003 and 2008 he and his colleagues propose an alternative model of fissural vents for explaining the large volume of ignimbrites and the relative lack of classic circular calderas.