Encyclopedia of Planetary Landforms

2015 Edition
| Editors: Henrik Hargitai, Ákos Kereszturi

Softened Crater

Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-3134-3_357

Definition

An impact crater displaying muted topography in a volatile-rich target material.

Synonyms

Terrain softened crater (antonym: unsoftened crater)

Description

Structure of impact craters depends on the target material (e.g., Strom et al. 1992; Barlow and Perez 2003; Stewart and Valiant 2006) and can exhibit distinct structures if the target is rich in volatiles (e.g., Senft and Stewart 2008). An impact into a target substrate that is volatile-rich or contains buried volatiles can result in a crater with a “softened” form compared to an impact into a substrate with no volatiles. Using imagery, Jankowski and Squyres ( 1992) assessed craters in the mid-latitudes of Mars for crater depth, convexity or concavity of crater wall, rounding of the crater rim, and rim height. They found that softened simple and complex craters had rounded rims and more convex crater-wall slopes; and otherwise sharp features were rounded (Figs. 1 and 2). Softened craters are shallower than unsoftened...
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Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  1. 1.Department of Earth and Space SciencesUniversity of WashingtonSeattleUSA