Geomorphological map of the South Belet Region of Titan

We mapped in detail Titan’s South Belet region which spans the area from longitude 60W to 120W (+W coordinates) and from latitude 60S to 0, encompassing both equatorial and southern mid-latitude regions. This mapping work is a continuation of the detailed global mapping effort introduced in Malaska et al. (2016a) and continued on in Lopes et al. (2020). We used Cassini Radar in its Synthetic Aperture Radar (SAR) mode data as our basemap but supplemented with additional datasets. We followed the mapping procedure described in Malaska et al. (2016a) for the Afekan Crater region and identified four major terrain classes in South Belet: craters, hummocky/mountainous, plains, and dunes. Each terrain class was subdivided into terrain units by characteristic morphology, including border shape, texture, general appearance, and radar backscatter. There are two terrain units that were not included in previous studies but were identified in our mapping of South Belet: “bright alluvial plains” and “pitted hummocky”. Similar to the Afekan Crater region, we find that plains dominate the surface make-up of South Belet, comprising ~ 47.0% of the mapped area. Unlike Afekan, the areal extent of the dunes closely rivals the dominance of plains, making up 43.0% of the mapped area. The next most widespread unit by area in the region following the dunes are the mountains/hummocky terrains (10.0%), and finally, crater terrains (0.01%). The introduction of two new units, “bright alluvial plains” and “pitted hummocky”, are necessary to capture the full range of morphologies seen in South Belet. However, analysis of our geomorphological mapping results suggests South Belet is consistent with the narrative of organics dominating the equatorial and mid-latitudes. This is similarly the conclusion we arrived at through our mapping and analysis of the Afekan region. Lastly, the applicability of the terrain units from our mapping of the Afekan region to our mapping of South Belet suggests latitudinal symmetry in Titan’s surface processes and their evolution.