GEOMORPHOLOGICAL MAP OF THE SOUTH BELET REGION OF TITAN: AN EXPLORATION OF MID-LATITUDE-TO-POLE TRANSITION ZONES

We carried out detailed geomorphological mapping of Titan’s mid-latitude region south of the Belet Sand Sea. We used radar data collected by Cassini’s Synthetic Aperture Radar (SAR) as our basemap, supplemented by images from VIMS, ISS, SARtopo, and microwave emissivity datasets. We mapped at a scale of 1:800,000 in all areas of the South Belet region covered by SAR swaths, taking into consideration the 300 m/pixel resolution of the swaths. For the mid-latitudes, we have defined five broad classes of terrains following Malaska et al. (2015). These terrain classes are craters, hummocky/mountainous, labyrinth, plains, and dunes. We have found that the hummocky/mountainous terrains are the oldest, with a radiometric signature consistent with icy materials. Dunes are the youngest units and return a radiometric signature consistent with organic sediments. We find that the South Belet region is covered primarily by the dune and plain units typical of Titan’s mid-latitudes (Malaska et al. 2015). Previous mapping efforts of the mid-latitude regions of Titan (Lopes et al. 2016; Malaska et al. 2015) have indicated that these regions are predominately modified and influenced by aeolian activities. A plains unit designated “scalloped plains” is prominently featured between the 50°S and 60°S latitudes of this region. In this area we also find a terrain unit designated “dark irregular plains” that has been interpreted as damp materials saturated with liquid hydrocarbons (Malaska et al 2015; Hayes et al. 2008). We also note a higher occurrence of fluvial channels starting at this latitude zone and extending poleward. We suggest that these features demark the transition zone between mid-latitude/equatorial aeolian-dominated processes and fluvial-dominated processes prevailing at the poles.