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Read Full Article (file size: 351535 bytes) Cited by
GEOPHYSICAL RESEARCH LETTERS,
VOL. 31,
L16703,
doi:10.1029/2004GL019978,
2004
Topographic variations in chaos on Europa: Implications for diapiric formation
Paul M. Schenk
Lunar and Planetary Institute, Houston, Texas, USA
Robert T. Pappalardo
Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, Colorado, USA
Abstract
Disrupted terrain, or chaos, on Europa, might have formed through melting of a floating ice shell from a subsurface ocean
[
Carr et al., 1998
;
Greenberg et al., 1999
], or breakup by diapirs rising from the warm lower portion of the ice shell [
Head and Pappalardo, 1999
;
Collins et al., 2000
]. Each model makes specific and testable predictions for topographic expression within chaos and relative to surrounding
terrains on local and regional scales. High-resolution stereo-controlled photoclinometric topography indicates that chaos
topography, including the archetypal Conamara Chaos region, is uneven and commonly higher than surrounding plains by up to
250 m. Elevated and undulating topography is more consistent with diapiric uplift of deep material in a relatively thick ice
shell, rather than melt-through and refreezing of regionally or globally thin ice by a subsurface ocean. Vertical and horizontal
scales of topographic doming in Conamara Chaos are consistent with a total ice shell thickness >15 km. Contact between Europa's
ocean and surface may most likely be indirectly via diapirism or convection.
Received 12
March
2004;
accepted 21
June
2004;
published 26
August
2004.
Index Terms: 5430 Planetology: Solid Surface Planets: Interiors (8147); 5455 Planetology: Solid Surface Planets: Origin and evolution; 6218 Planetology: Solar System Objects: Jovian satellites.
Read Full Article (file size: 351535 bytes) Cited by
Citation: Schenk, P. M., and R. T. Pappalardo
(2004),
Topographic variations in chaos on Europa: Implications for diapiric formation,
Geophys. Res. Lett.,
31,
L16703,
doi:10.1029/2004GL019978.
Copyright 2004 by the American Geophysical Union.
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