JOVIAN SYSTEM DATA ANALYSIS PROGRAM PROPOSAL SUMMARY

The tectonic character of Europa, its history, and its current state will be investigated by synthesis of information from Galileo imaging and other sources. Our interdisciplinary approach will explore the intimately connected roles of tidal, orbital, tectonic, geophysical, and geological processes, and will include analysis of Galileo orbiter imaging data and modeling the physical processes involved. Formation of cracks will be investigated by refining our global stress models for correlation with global lineament patterns, crack propagation processes, and regional tectonics. A comparative study of models of ridge formation on Europa will include analysis of observed morphologies, mapping, classification, and quantitative theoretical analysis to test competing hypotheses. Displacement features, including lateral shear offsets, dilation, and vertical flexure, combined with theoretical models of tidal working and geological response, will provide key constraints. The chronological interplay on Europa between regional chaos episodes and on-going crack-and-ridge formation will be investigated by mapping and theoretical modeling. These investigations will help place constraints on global geophysical and geological evolution, and determine any correlation with long-term orbital evolution, which may have modified the tidal processes that underlie Europan tectonics.