Encyclopedia of Planetary Landforms

2015 Edition
| Editors: Henrik Hargitai, Ákos Kereszturi

Shield Volcano (Io)

  • Ashley Gerard Davies
Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-3134-3_335


Volcanic edifice constructed almost entirely from an accumulation of fluid, low-viscosity lava flows, leading to a characteristic shield-like profile.


A type of  volcanic mountain (Io).


Many of Io’s shield volcanoes are associated with a central edifice (Moore et al. 1986) (Fig. 1). Some have nested summit calderas. Io lacks any Olympus-Mons-like towering volcanic edifices (Schaber 1982). Several shield volcanoes appear to be associated with broad rises of 1–3 km in height. Only five shield volcanoes have been identified with steep flank slopes between 4° and 10°, with these steep slopes restricted to within 20–30 km of the summit (Schenk et al. 2004). The concave profile of the upper slopes is reminiscent of composite volcanoes on Earth. From these steep-sided shields emanate long, radial flows of which the best known are Maasaw Patera and Ra Patera (Fig. 2). The 45 shield volcanoes identified on Io by Schenk et al. ( 2001) make up ∼8 % of the ∼550...
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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Jet Propulsion LaboratoryCalifornia Institute of TechnologyPasadenaUSA