Advances in the Study of Volcanic Ash

Every month, small-scale explosive volcanic
eruptions inject more than a million
cubic meters of ash into Earth’s
atmosphere [Simkin and Siebert, 2000]. Of
all the troubles caused by this relatively
mild volcanic activity, ashfall is by far the
longest-reaching one, mantling the volcano
slopes and surroundings with a slippery,
heavy, unhealthy, and snow-like but
Sun-resistant cover.
Volcanic ash is composed of pyroclasts
(fragments generated and emplaced by
explosive eruptions) smaller than 2 millimeters,
which are easily transported by wind
and have a high surface-to-volume ratio.
These same features, however, also allow safe
collection of the ash away from the volcano.
Such pyroclasts bear the signature of the
fragmentation and dispersal processes they
have experienced during eruption and transport.
Thus, volcanic ash provides sample
material well suited for studying quasi time
correlated eruption dynamics [Taddeucci et
al., 2002].
Here we illustrate how current research
projects funded by the Italian Department
for Civil Protection combine new sampling,
analytical, and experimental techniques to
maximize the extraction of useful information
from basaltic volcanic ash.