Pits and uplifts on Europa

Richard J. Greenberg, Martha A. Leake, Gregory V. Hoppa, B. R. Tufts

Research output: Contribution to journalArticle

25 Citations (Scopus)

Abstract

A survey of depression and uplift features on Europa, based on Galileo regional mapping images, shows that these features come in a wide range of sizes, with numbers increasing greatly with decreasing size, down to the limits of resolution. Size distributions are similar in the northern leading and southern trailing hemispheres, where they are distinctly different from the southern leading and northern trailing hemispheres, suggesting an oblique, antipodal symmetry pattern, similar to that of chaotic and tectonic terrain. This pattern is suggestive of polar wander. Uplifts are usually polygonal or irregular in shape and rarely are cracked. Patches of chaotic terrain, which we had surveyed earlier, are not included in the current study because their topography is generally unclear, and because there is no a priori known genetic linkage with the pits and uplifts. These results contradict generalizations based on the earlier "pits, spots, and domes" (PSD) taxonomy. Most of the type examples for PSDs were simply patches of chaotic terrain selected from a limited portion of their full size range. The use of the term lenticula to collectively describe PSDs is inconsistent with the IAU definition of lenticula: a small dark spot seen at low resolution. Pits and uplifts do not correlate with lenticulae, although chaos often does. Properties of PSDs that have been widely cited as primary evidence for convective upwelling in thick ice (e.g., that uplifts are generally dome-shaped and often cracked; that pits and domes are regularly spaced; that there is a typical diameter of ∼10 km) were premature and not supported by subsequent data. Most pits and uplifts are less than 10 km across so, if they formed by diapirism or convective upwelling, the sources must have been very shallow, less than 5 km deep. How they actually formed remains unknown.

Original languageEnglish (US)
Pages (from-to)102-126
Number of pages25
JournalIcarus
Volume161
Issue number1
DOIs
StatePublished - Jan 1 2003

Fingerprint

Europa
uplift
domes
dome
upwelling water
hemispheres
upwelling
taxonomy
diapirism
linkages
chaotic dynamics
chaos
tectonics
topography
ice
range size
Southern Hemisphere
symmetry
Northern Hemisphere

Keywords

  • Europa
  • Geological processes
  • Ices

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Greenberg, R. J., Leake, M. A., Hoppa, G. V., & Tufts, B. R. (2003). Pits and uplifts on Europa. Icarus, 161(1), 102-126. https://doi.org/10.1016/S0019-1035(02)00013-1

Pits and uplifts on Europa. / Greenberg, Richard J.; Leake, Martha A.; Hoppa, Gregory V.; Tufts, B. R.

In: Icarus, Vol. 161, No. 1, 01.01.2003, p. 102-126.

Research output: Contribution to journalArticle

Greenberg, RJ, Leake, MA, Hoppa, GV & Tufts, BR 2003, 'Pits and uplifts on Europa', Icarus, vol. 161, no. 1, pp. 102-126. https://doi.org/10.1016/S0019-1035(02)00013-1
Greenberg RJ, Leake MA, Hoppa GV, Tufts BR. Pits and uplifts on Europa. Icarus. 2003 Jan 1;161(1):102-126. https://doi.org/10.1016/S0019-1035(02)00013-1
Greenberg, Richard J. ; Leake, Martha A. ; Hoppa, Gregory V. ; Tufts, B. R. / Pits and uplifts on Europa. In: Icarus. 2003 ; Vol. 161, No. 1. pp. 102-126.
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