Page 72 - Caldera Volcanism Analysis, Modelling and Response

Residence Times of Silicic Magmas Associated with Calderas 47

(5) These magma production rates and residence times are important parameters
for rheological models of the crust and their relation to magmatic inputs and
eruption. However, the retrieved times are much longer and the fluxes
inappropriate to reach the critical overpressure necessary for eruption
of a large reservoir as indicated by a simplified rheological model of the crust.
The discrepancy may be partly explained if the magma production rates
are mean values of a highly variable magma influx. Further interactions
between residence times and rheological models are necessary for the
understanding of the mechanisms by which large magma reservoirs are
constructed and stored in the shallow crust awaiting to produce a caldera-
forming eruption.

ACKNOWLEDGMENTS

This manuscript was only possible thanks to the detailed field, petrographical, analytical, and
modelling work of the authors in the reference list. Reviews by O. Bachmann and J. Wolff helped to
clarify the text and figures. J. Hansen helped with the English language. Thanks to J. Martı ´ and
J. Gottsmann for providing the opportunity to write this paper. A Ramon y Cajal Fellowship
from the Ministerio de Educacio ´n y Ciencia de Espan ˜a and the DFG (SFB 526, project B7) supported
this work.

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