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The Valle de Bravo Volcanic Field is one of four monogenetic volcanic fields identified in the central sector of the Mexican Volcanic Belt. Michoacán-Guanajuato, Jilotepec, and Chichinautzin are the other three. The Valle de Bravo Volcanic Field is located at the southern front of the belt where it covers the western flank of the Pleistocene-Holocene Nevado de Toluca volcano. It covers an area of 3703 km2 and includes at least 120 cinder cones, one shield volcano, a few lava domes, and two lava dome complexes. It overlies a rough paleotopography of Mesozoic metamorphic rocks (schists, metalimestones, and pillow lavas), Paleocene-Eocene granitic rocks, and Eocene-Oligocene ignimbrites. Based upon morphometric parameters that were calibrated with reported isotopic ages, four groups of cinder cones were identified, older than 40 ka, 40–25 ka, 25–10 ka, and younger than 10 ka. Lava domes occur sporadically as high domes, low domes, and coulees, with ages between Pliocene to Pleistocene. We also observed several mafic lava flows that lack a cone source, suggesting that they erupted from fissures. A geomorphologic analysis of the cinder cones indicates a relatively young age for most of them, since craters are still evident and flanks are little eroded. Many lava flows still show levees and some of them are little vegetated and lack soil, which is significant for this densely forested and humid area. An analysis of the distribution of the cinder cones shows that most vents follow a NE alignment. By contrast, the domes tend to be aligned in a NW trend. This suggests that emplacement of cinder cones follows the maximum horizontal compressional stress direction, parallel to the Cocos–North America plate convergence (NE), whereas the lava domes are better developed along the minimum horizontal stress direction, perpendicular to convergence (i.e., NW).

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