Geol. Soc. Am. Bull. https://doi.org/jzf (2012)

Credit: © 2012 GSA

A decade ago, the Cassini–Huygens mission revealed that the surface of Saturn's moon, Titan, seemed to have been sculpted by flowing liquids, primarily methane. Further imaging of Titan's diverse fluvial landscapes shows that the sedimentary and hydraulic processes that occur on Titan's surface are often similar to those that occur on Earth.

Devon Burr at the University of Tennessee-Knoxville and colleagues analysed the morphology of fluvial features as observed in ten years of Cassini–Huygens data. They combined the spacecraft radar imagery with insights from process mechanics and terrestrial analogues. In the valley networks near the Huygens probe landing site, the morphology is consistent with mechanical erosion of sediment by overland channelled flows, probably fuelled by alkane rains. Sediment deposition occurs in braided river channels, extant and former lake basins and along some plains. However, it isn't immediately clear how or where these sediments were created.

Precipitation and run-off during seasonal storms on Titan, spurring flows capable of moving many different sizes of sediment, can explain many of the surface features. The area of Titan's surface affected by this fluvial dissection is around an order of magnitude greater than that inferred from visible fluvial networks alone.