The Emerging Resurfacing History of Europa from Pole-to-pole Geologic

Introduction Geologic mapping of planetary surfaces provides information on the nature, sequence, and distribution of material units, from which one can assemble a geologic history [1]. With this goal in mind, the Galileo SSI camera acquired an important dataset of images of Europa at a resolution suitable for geologic reconnaissance and mapping. We performed mapping and analysis of pole-to-pole transects at 230 m/pixel (covering about 10% of the satellite) across the leading and trailing hemispheres of the satellite. Here we report the results on the spatial and temporal distribution of surface units, and their implications for the resurfacing history of Europa. We show that a) the style of tectonic and cryovolcanic resurfacing changed with time, and b) these changes could reflect the thickening of Europa s lithosphere during its recent geologic hi story.