Estimate of depths of source fluids related to mound fields on Mars

The investigation of the Martian surface through remote sensing allowed the identification of mound-like topographically positive features that, based on geomorphological observations, have been ascribed to different phenomena. New observations will be performed in the forthcoming future to look for possible methane sources, hence discriminating morphologically similar features is a key objective to efficiently investigate and target the Martian surface. Here, we performed fractal analysis on five Martian fields of mound-like features that have been interpreted respectively as mud volcanoes, pingos, tumuli, rootless cones and monogenetic volcanic vents successfully validating the major interpretations of these features and in turn, the applicability of the fractal clustering method for discriminating among such features. Indeed, this technique is able to assess if the analyzed features are directly related to underlying systems of connected percolating fracture networks and estimates their extension in the subsurface. Accordingly, volcanic vents and mud volcanoes appeared to be connected to percolating systems involving several kilometers of crust, pingos and tumuli resulted to be unequivocally unrelated to active percolating fractures while rootless cones outputted weak relationship with shallow active fracture systems.