The Lago Sofia conglomerate lenses in the Upper Cretaceous Cerro Toro Formation of southern Chile represent a channel-levee facies on a north-to-south-oriented deep-sea fan that formed between the rising cordillera to the west and the South American craton to the east. The enclosing Cerro Toro flysch represents overbank and pelagic deposits. Most of the conglomerates have features developed by tractive transport; they are moderately well sorted, imbricated, and have both horizontal and inclined internal stratification. Large-scale dunes up to 4 m high are present. Fabrics and bedding styles considered typical of gravity flows are less common. Features produced by traction transport apparently were developed in the gravel by rolling, sliding, and saltation as the bedload component of highly turbulent, probably low-density, turbidity currents flowing in a confined channel.