HR: 12:05h
AN: P31C-08    [PDF]
TI: Analysis of faults on the icy surface of Jupiter's moon Europa based on failure modes
AU: * Atilla, A
EM: aydin@stanford.edu
AF: Stanford University, Department of Geological and Environmental Sciences, Stanford, CA 94305-2115 United States
AB: I have analyzed faults on the surface of Europa using high resolution images by the Galileo spacecraft. Based on the geometric characteristics of the faults and possible analog structures from the planet Earth, I have identified two mechanisms leading to fault formation on Europa. The first one is characterized by well organized sub parallel shear bands representing shear and perhaps volumetric strain localization. The second one is associated with mode-I fractures and their subsequent sliding/shearing. Faults in this group appear to be chaotic defined by zones of fragmentation and brecciation often with broad curvilinear boundaries. Where the two system overprint, the group with the sheared mode-I fractures is always younger suggesting a significant change in the environmental conditions at some time in the history of the planet. The shear band based faults are expected to be composed of ice deformed and perhaps transformed in situ with a lower permeability than the surrounding ice matrix. Whereas, the sheared fracture based faults may have significant pore space and therefore, may be conduits for subsurface mobile fluids to rise up to the surface of the planet. This later group has the potential to provide evidence for life in and on the planet.
DE: 5475 Tectonics (8149)
DE: 8010 Fractures and faults
DE: 8045 Role of fluids
SC: Planetary Sciences [P]
MN: 2003 Fall Meeting