INSIGHT INTO SURFACE PROCESSES ON EUROPA THROUGH GEOLOGIC MAPPING AT THE GLOBAL SCALE

Evaluating the potential habitability of the icy ocean worlds of the outer planets requires an understanding of three main components, the chemistry and composition of the material making up the body, the sources of chemical disequilibrium available for potential metabolic processes, and the geology that drives the interaction between the surface and the deeper interior of the body. For Europa, we have focused on the latter area, creating a global geologic map at the scale of 1:15M. The geologic units can be divide into four categories: (1) crater materials and its subunits, continuous crater ejecta and discontinuous crater ejecta—including the primary impact crater and its local deposits and farther ranging ejecta material; (2) Various morphological types of chaos materials identified as high albedo, mottled, low albedo, and knobby chaos—disrupted terrains; (3) General band forming material and high albedo bands—linear to curvilinear zones with a distinct, abrupt albedo change from the surrounding region; and (4) ridged plains—distributed across all latitudes and characterized by subparallel to cross-cutting ridges and troughs. In addition, a number of structural features are identified including: depression margins, troughs, multi-ring structures, microchaos, cycloids, band linea, ridges, and undifferentiated linea. The distribution of microchaos is not uniform across the surface, showing a general association with band forming materials. Concentrations of microchaos could correspond with areas of crustal weakness or thinning. We are currently in the process of calculating the distribution and global trends of bands, ridges, and cycloids, which could have implications for ice shell evolution through time. In this presentation we will further discuss the implications for microchaos distribution as well as evaluate global trends of different linea types.