Page 435 - Caldera Volcanism Analysis, Modelling and Response

410 Micol Todesco

does not take into account their effects on fluid circulation. Further work is needed
on these coupled processes, including thermal, chemical and mechanical effects and
their feedback on fluid circulation. Development of numerical models should also
include a better description of fluid properties through the transition from subcritical
to supercritical temperatures, and under the extreme conditions that characterise
active volcanic systems. Implementation of inverse modelling, directly incorporating
data from monitoring networks, would greatly improve our ability to interpret
signals gathered during unrest and could contribute to volcanic hazard assessment.
Another important aspect to be considered in future research is the connection
between models and observations. This should be improved to ensure at least some
degree of model calibration. Therefore, it is necessary to develop models that describe
parameters that can be measured in the natural system. We cannot access
hydrothermal system at depths and consequently we cannot compare simulated flow
variables to direct measurements of pressure or phase saturation. We need to convert
modelling results into a larger number of observables, such as gravity changes, which
can be actually compared with available data. Preliminary successful results are
encouraging, but the comparison between observation and modelling results should
be performed over a larger number of physical and chemical data. Coordinated
monitoring campaigns are necessary to provide simultaneous measurements of
different geochemical and geophysical parameters. Simultaneous matching of
independent data sets is an effective way to validate modelling results. Monitoring
data and modelling results should freely circulate inside the scientific community to
ensure a continuous positive feedback, with prompt updating of the conceptual
model, progressive refinement of model calibration and rational optimisation of
monitoring activities.

ACKNOWLEDGMENTS
This work was greatly improved by comments and discussions with Laura Sandri, Lucia Zaccarelli and
Benjamin N. Fackler-Adams, who tried to correct my poor English usage. Two anonymous reviewers
are also acknowledged for their useful comments.

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