TITLE:
Classification of River Reaches on the Little Disturbed East Alligator River, Northern Australia
AUTHORS:
Michael John Saynor, Wayne D. Erskine
KEYWORDS:
River Reaches; River Types; Sandstone Gorge; Anabranching Rivers; Cuspate Tidal Meanders; Wetlands and Channel Billabongs
JOURNAL NAME:
International Journal of Geosciences,
Vol.4 No.6B,
August
22,
2013
ABSTRACT: The East Alligator River drains a 7000 km2 catchment in northern Australia comprised largely of Aboriginal land and has a
very low average population density of about 0.15 persons per km2.
River reaches were classified according to geomorphic features on both the East
Alligator River and its major tributary, Magela Creek, next to which is located
the Ranger uranium mine. Sixteen reaches were described for the 241.4 km of the
East Alligator River and ten reaches were described for the 118.8 km of Magela
Creek. The dominant river types on the East Alligator River were various types
of anabranching rivers, sandstone gorges and cuspate tidal meanders. On Magela
Creek the dominant river types were wetlands and channel billabongs, island
anabranching and sandstone gorges. It is unusual for anabranching rivers and
gorges to be so dominant. Current river classification schemes could not
accommodate all the various river types and need to be modified so that tidal
channels are covered in more detail and so that the classification of
anabranching rivers recognises that sand-bed varieties occur in partly confined
valley settings.