Global Tectonics on Ganymede

Three large basin surroundings on Ganymede located on grooved terrains, which are supposed to be intensely tectonized areas were studied. All rectilinear morphological elements such as ridges, block edges; and parts of scarps were mapped. The geometric properties (grid pattern) characteristics were determined and a history for the formation of the Ganymede basins studied is proposed. Results indicate that the grooved terrains are very surficial layers, and that their formation does not significantly affect, disturb or rotate the basement. This is in agreement with the conclusion obtained from completely different data (crosscutting relationships between groove sets and their basements).