Editing Titan (moon) (section)

=== Plains and dunes ===
[[File:Titan globe.jpg|thumb|right|''Cassini'' mosaic of Titan's equatorial dark regions, including the vast dune fields.]]
The majority of Titan's surface is covered by plains. Of the several types of plains observed, the most extensive are the Undifferentiated Plains that encompass vast, radar-dark uniform regions.<ref name="Lopes2019"/>{{rp|15}}
These mid-latitude plains—located largely between 20 and 60° north or south—appear younger than all major geological features except dunes and several craters.<ref name="Lopes2016"/>{{rp|177}} The Undifferentiated Plains likely were formed by wind-driven processes and composed of organic-rich sediment.<ref name="Lopes2016">{{cite journal |last1=Lopes |first1=Rosaly M. C. |author-link=Rosaly Lopes |display-authors=et al. |title=Nature, distribution, and origin of Titan's Undifferentiated Plains |date=May 2016 |journal=Icarus |volume=270 |pages=162–182 |doi=10.1016/j.icarus.2015.11.034 |bibcode=2016Icar..270..162L }}</ref>{{rp|180}}

Another extensive type of terrain on Titan are sand dunes, grouped together into vast dune fields or "sand seas" located within 30° north or south. Titanian dunes are typically 1–2 km (0.62–1.24 mi) wide and spaced 1–4 km (0.62–2.49 mi) apart, with some individual dunes over 100 km (62 mi) in length. Limited radar-derived height data suggests that the dunes are {{convert|80|–|130|m|ft}} tall, with the dunes appearing dark in ''Cassini'' SAR imagery. Interactions between the dunes and obstacle features, such as mountains, indicate that sand is generally transported in a west-to-east direction. The sand that constructs the dunes is dominated by organic material, probably from Titan's atmosphere; possible sources of sand include river channels or the Undifferentiated Plains.<ref name="Lopes2019"/>{{rp|16–18}}