Encyclopedia of Planetary Landforms

2015 Edition
| Editors: Henrik Hargitai, Ákos Kereszturi

Chaotic Terrain (Europa)

Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-3134-3_45


Surface regions on Europa where the original ice crust is fragmented and low level matrix material between these rafts formed by thinning and possibly melting.


Chaos terrain, smaller occurrences also known as lenticulae; Macula;  Microchaos;  Mottled terrain;  “Pits, spots, and domes”


Chaotic terrain on Europa is composed of regions of fragments of the preexisting ice crust, such as  ridged plains, separated by a low-level chaotic, hummocky matrix material. The shape of the individual fragments varies from smoothly circular to polygonal blocks of ridged terrain (Mikell and Cox 2008; Doggett et al. 2009). The matrix material can be either low lying or high standing relative to the surrounding plains (Collins et al. 2000; Greeley et al. 2000). Chaoses and lenticulae can be elevated by 100–200 m above their surroundings (Figueredo et al. 2002; Schenk and Pappalardo 2004). Some of the individual plates sometimes appear to have moved from their original...

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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Planetary GeologyGerman Aerospace Center, Institute of Planetary ResearchBerlinGermany
  2. 2.Konkoly Thege Miklos Astronomical InstituteResearch Centre for Astronomy and Earth SciencesBudapestHungary