Spatial variability in fluvial style and likely responses to sea level change, Herbert River, Queensland

Abstract

In broad terms, fluvial systems can be considered as comprising two basic geomorphologic features, a channel and its floodplain (overbank), each of which may accumulate sediment or undergo erosion. The sedimentary relationships between channels and floodplains, the resultant sedimentary architecture and the form of the dependent landscape may all be considered in terms of the relative rates of channel and floodplain aggradation and/or erosion. Using this approach, the Herbert River in north Queensland can be divided into seven 'fluvial fields'. By considering the likely migration directions of field boundaries in the lower floodplain we conclude that, contrary to many sequence-stratigraphic models, lowering sea-level would drive a general aggradation of the system on the Great Barrier Reef shelf, whereas a sea-level rise would cause further incision of the modern coastal plain.