Volume 69 of Reviews in Mineralogy and Geochemistry covers the fundamental issues of
volcanology: At what depths are eruptions triggered and over what time scales? Where and why
do magmas coalesce before ascent? If magmas stagnate for thousands of years what forces are
responsible for initiating final ascent or the degassing processes that accelerate upward
motion? To the extent that we can answer these questions we move towards formulating tests of
mechanistic models of volcanic eruptions (e.g. Wilson 1980 Slezin 2003 Scandone et al.
2007) and hypotheses of the tectonic controls on magma transport (e.g. ten Brink and Brocher
1987 Takada 1994 Putirka and Busby 2007). Our goal in part is to review how minerals can
be used to understand volcanic systems and the processes that shape them we also hope that
this work will spur new and integrated studies of volcanic systems.