Geology of large impact craters on Ganymede: Implications on thermal and tectonic histories

The geometry of the furrows of Galileo Regio indicates that they are not of impact origin, and irrelevant to discussion about large impact effects. The detailed study of three large impact basins indicates that their transient cavity radii are different from previously reported values. Because of the relations between crater's size and lithospheric thickness, these new values of basins radii would constrain further models of Ganymede's thermal evolution. The geometry of lineaments around these three basins, which occurred on grooved terrains, indicates that these impacts induced tectonic motions along a preexisting planetary wide grid pattern. This pattern influenced also the formation of the furrows on Galileo Regio. That would indicate that the grooved terrains are only superficial layers and that they were formed without destruction or rotation of their basement.