Page 184 - Fundamentals of Physical Volcanology

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ERUPTION STYLES, SCALES, AND FREQUENCIES 161

1000

Mauna 2000 4000
Kea 5000
3000

Mauna 150
Loa 300
Cape
Kumukahi
450
Kapoho
600
Kilauea 900 750 Heiheiahulu
Caldera
Kalalua
Napau
Pu'u 'O'o
Mauna Makaopuhi
Ulu N

Cinder or spatter cone
Pit crater
Large pit crater
20 km Crest of Puna Ridge

Fig. 10.10 Map of a portion of the island of Hawai’I showing the subaerial and submarine topography of Kilauea volcano.
The submarine ridge which extends offshore is known as the Puna Ridge and is the submarine extension of Kilauea’s East
Rift Zone. (Adapted from fig. 1 published in Journal of Volcanology and Geothermal Research, Vol 113, Parfitt, E.A., Gregg,
T.K.P. and Smith, D.K., A comparison between subaerial and submarine eruptions at Kilauea volcano, Hawai’I: implications
for the thermal viability of lateral feeder dikes, 213–242, copyright Elsevier (2002).)

eruptions (Table 10.5). The fact that the largest
10.8.2 Large ignimbrite-forming eruptions
eruptions are confined to only these two eruption
types suggests that there is something special about The largest ignimbrite-forming eruptions (Table
them which produces such exceptionally large vol- 10.5) are all associated with caldera formation.
umes of material. What is it about these eruptions They are “inelastic” eruptions of the type described
which allow them to produce such large volumes in section 10.7 and are able to produce an excessive
and what controls the upper limit on the scale of volume of material because they are not limited by
these eruptions? The two types of eruption differ elastic processes. The very largest eruptions prob-
greatly from each other and so in answering these ably form part of a continuum of eruption scales
3
questions we will consider each type separately. from a minimum size of around 10 km . The scale