Characterizing large river history with shallow geophysics: Middle Yukon River, Yukon Territory and Alaska

The consistency of gravel-fill and scour hole depth, and lack of Holocene terraces along the 1000 km reach of the Yukon, indicate that the river has been in a state of mass-balance equilibrium of sediment transport (input=output) over the Holocene. Despite massive sediment influxes from the glacial-fed White River and crossing major faults, variation in valley-fill depth is not significant. And further, the Yukon Flats reach shows no evidence of bed aggradation during the Pleistocene and has probably existed in equilibrium since the late Pliocene.