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Country: | México | |
| Subregion Name: | México | ||
| Volcano Number: | 1401-031 | ||
| Volcano Type: | Cinder cones | ||
| Volcano Status: | Holocene | ||
| Last Known Eruption: | Unknown | ||
| Summit Elevation: | 2560 m | 8,399 feet | |
| Latitude: | 20.62°N * | 20°37'0"N | |
| Longitude: | 104.83°W | 104°50'0"W | |
| A group of calc-alkaline andesitic and minette cinder cones and lava domes, both with associated lava flows, is located near the town of Mascota, in the Jalisco tectonic block about 50 km east of Puerto Vallarta. Mascota is the youngest of a group of potassic volcanic fields in extensional grabens of the Jalisco block south of the Río Ameca. Most volcanism in the Mascota volcanic field is confined to two NNW-SSE-trending grabens cutting Cretaceous ash-flow tuffs. The youngest eruption, at Volcán Malpaís, north of Mascota, produced a fresh-looking basaltic-andesite lava flow. The lack of soil development and sparse vegetation suggest that it may be only a few thousand years old (Carmichael et al., 1996). The volcanic field is noted for its unusual diversity of volcanic rocks, and Mascota contains Earth's youngest known minettes, with radiometric ages down to 0.07 +/- 0.08 million years. | |||
