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ERUPTION STYLES, SCALES, AND FREQUENCIES 157

Table 10.5 Examples of some of the largest volcanic eruptions occurring in the geological record.
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Deposit/age Volcanic center/caldera Erupted volume (km ) Type of deposit
Fish Canyon, ~28 Ma La Garita, Colorado 5000 Ignimbrite
Huckleberry Ridge, ~2 Ma Yellowstone, Wyoming 2450 Ignimbrite
Individual Grande Ronde flow, Columbia River Flood > 2000 Lava flow
~16 Ma Basalts, USA
Cerro Galan, ~2.2 Ma Cerro Galan, Argentina 2000 Ignimbrite
Toba, ~75 ka Toba, Sumatra 1500 Ignimbrite
Carpenter Ridge, ~27 Ma Bachelor, Colorado 1350 Ignimbrite
Roza Flow, ~15 Ma Columbia River Flood Basalts, USA 700 Lava flow

Data taken from Lipman, P.W. (2000) Calderas. In Encyclopedia of Volcanoes (Ed. H. Sigurdsson), pp. 643–662. Academic
Press, San Diego, CA; Reidel, S.P. and Tolan, T.L. (1992) Eruption and emplacement of flood basalt: an example from the large-
volume Teepee Butte member, Columbia River Basalt Group. Geol. Soc. Am. Bull., 104, 1650–1671; Self, S., Thordarson, T. &
Keszthelyi, L. (1997) Emplacement of continental flood basalt lava flows. In Large Igneous Provinces: Continental, Oceanic,
and Planetary Flood Volcanism (Eds J.J. Mahoney & M.F. Coffin), pp. 381–410. Geophysical Monograph 100, American
Geophysical Union, Washington, DC; Simkin, T. & Seibert, L. (2000) Earth’s volcanoes and eruptions: an overview. In
Encyclopedia of Volcanoes (Ed. H. Sigurdsson), pp. 249–261. Academic Press, San Diego, CA.

relatively large eruption but the 2 Ma eruption of eruptions are flood basalt eruptions. These pro-
Yellowstone is equivalent to 2000 Mount St Helens duce very large-scale lava flows: flows often extend
eruptions! hundreds of kilometers from their vent systems and
The largest eruptions recorded in the geological individual flows are typically 20 to 100 m thick.
record are of two very different types. The large Individual flood basalt flows may have volumes
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eruptions of volcanic centers such as Yellowstone in excess of 2000 km (Table 10.5) and are found
in the western USA produce pyroclastic deposits, in sequences of flows, one on top of the other
both fall deposits and ignimbrites, with the latter (Fig. 10.7), such that the volume of a single flood
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being dominant. The other class of large-volume basalt province can be as much as 10 km .

Fig. 10.7 Part of the Deccan Volcanic
Province, western India, an enormous
stack of ∼65 Ma-old flood-basalt lava
flows. The flows, the cores of which
are the dark layers in the image, are
typically ∼30–40 m thick. The Deccan
is one of the world’s large igneous
provinces. (Image courtesy of Stephen
Self.)