Abstract
Rhyolitic domes are commonly regarded as monogenetic volcanoes associated with single, brief eruptions, in contrast to andesitic or dacitic domes that usually show a complex evolution including alternating long periods of growth and explosive destruction. Rhyolitic domes are characterized by short-lived successions of pyroclastic and effusive activity associated with a series of discrete eruptive events that apparently last on the order of years to decades or perhaps up to centuries. Cerro Pizarro, a rhyolitic dome in the eastern Mexican Volcanic Belt, is a relatively small (~ 1.1 km3), isolated volcano that shows aspects of polygenetic volcanism including long-term repose periods (~ 50-80 ky) between eruptions, chemical variations over time, and a complex evolution of alternating explosive and effusive eruptions, including a cryptodome phase, a sector-collapse event and prolonged erosional processes. This eruptive behavior provides new insights into how rhyolite domes may evolve, in contrast to the traditional models of rhyolitic domes as short-lived, monogenetic systems. A protracted, complex evolution bears important implications for hazard assessment if reactivation of an apparently extinct rhyolitic dome must be seriously considered.
Original language | English (US) |
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Pages (from-to) | 307-315 |
Number of pages | 9 |
Journal | Journal of Volcanology and Geothermal Research |
Volume | 171 |
Issue number | 3-4 |
DOIs | |
State | Published - Apr 20 2008 |
Keywords
- Mexican Volcanic Belt
- dome growth
- monogenetic volcanism
- polygenetic volcanism
- rhyolites
- volcanic hazards
ASJC Scopus subject areas
- Geophysics
- Geochemistry and Petrology