Topographic variations in chaos on Europa: Implications for diapiric formation
Article first published online: 26 AUG 2004
Copyright 2004 by the American Geophysical Union.
Geophysical Research Letters
Volume 31, Issue 16, August 2004
How to Cite
2004), Topographic variations in chaos on Europa: Implications for diapiric formation, Geophys. Res. Lett., 31, L16703, doi:10.1029/2004GL019978., and (
- Issue published online: 26 AUG 2004
- Article first published online: 26 AUG 2004
- Manuscript Accepted: 21 JUN 2004
- Manuscript Received: 12 MAR 2004
 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.