“…According to Davis (1898), a very gentle (0.0148 = 0.0002) depositional landform formed by the Yellow River in China is one of the largest alluvial fans in the world. Another large and gentle landform formed by the Kosi River at the foot of Himalayas (0.0198 = 0.0003; Stanistreet and McCarthy, 1993) has been called a wet fan (Schumm, 1977), mega-cone (Parkash et al, 1980), large flat fan (Wells and Dorr, 1987), and megafan (Gohain and Parkash, 1990). Such gentle fans with many distributary channels, which have been sedimentologically called fluvial distributary systems (Nicols and Hirst, 1998), also occur in the other Himalayan piedmonts and along the Andes (Singh et al, 1993;Iriondo, 1993;Sinha and Friend, 1994;DeCelles and Cavazza, 1999).…”