Page 30 - Fundamentals of Physical Volcanology

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VOLCANIC SYSTEMS 7

Fig. 1.11 The type of pyroclastic density current called a
pyroclastic surge or nuée ardente. This surge is one of a
Fig. 1.10 A pyroclastic density current formed by partial series from Mount Pelée volcano, Martinique, that destroyed
collapse of an eruption column during the January 1974 the town of St Pierre in 1902. (Photograph taken on
eruption of Ngauruhoe volcano, New Zealand. The eruption December 16, 1902 by A. Lacroix.)

column is approximately 4 km high. (Photograph credit:
University of Colorado, courtesy of the National Oceanic
and Atmospheric Administration, National Geophysical
Data Center.)

town jail. The kind of dilute, fast-moving cloud
which destroyed Mount Pelée is sometimes called a
nuée ardente (Fig. 1.11).

1.2.6 Strombolian eruptions
The eruptions described thus far are all types of
sustained eruption. Other eruptions, though, are
transient in character and consist of discrete explo-
sions of short duration. One example is the type
of eruption called Strombolian, named after the
Fig. 1.12 Approximately 120 m high ash-rich eruption
volcanic island Stromboli in the Mediterranean Sea, cloud from a Strombolian explosion at Stromboli volcano,
which usually involves basaltic magma. Strombolian Italy. (Photograph by Matt Patrick, University of Hawai’I.)