Assessing Environmental Factors of Alluvial Fan Formation on Titan

Abstract

Present-day environmental conditions on Titan, the largest moon of Saturn, may do active geomorphic work on its surface. On Earth, the hydrologic water cycle erodes and weathers its continents. Deluges over elevated terrain create debris flows and sheetfloods that spread into alluvial fans as the topographic slope decreases. Mars also shows evidence of past fluvial erosion, but fluvial activity cannot be ongoing in the present. On Titan, however, fluvial erosion is likely ongoing. In this study, we focus on understanding the environmental controls on the spatial distributions of alluvial fans, a type of fluvial depositional feature observed globally on the surface of Titan. To do this, we utilize probabilistic models to determine the strength of spatial correlations between spatial distributions of alluvial fans and present-day environmental factors. We find that the spatial distribution of alluvial fans on Titan correlates well with several present-day environmental conditions, including average precipitation, precipitation variability, and elevation. Based on our model, we also provide predictions of the likelihood of alluvial fan occurrences for areas of Titan not mapped with Cassini, which may be of interest for future missions to Titan.