Record number :
2245477
Title of article :
Polygenetic nature of a rhyolitic dome and implications for hazard assessment: Cerro Pizarro volcano, Mexico
Author/Authors :
Carrasco-Nٌْez، نويسنده , , G. and Riggs، نويسنده , , N.R.، نويسنده ,
Issue Information :
روزنامه با شماره پیاپی سال 2008
Pages :
9
From page :
307
To page :
315
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.
Keywords :
Rhyolites , volcanic hazards , dome growth , Mexican Volcanic Belt , polygenetic volcanism , Monogenetic volcanism
Journal title :
Journal of Volcanology and Geothermal Research
Serial Year :
2008
Link To Document :
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