Composition and textural variability along the 10m isobath, Great Barrier Reef: evidence for pervasive northward sediment transport

Previous workers have proposed that northward-directed bedload transport do minates the inner shelf of the Great Barrier Reef lagoon. Results from a se diment sampling survey along the in m isobath between Bowen and Cape York r eveal a series of northward trends of increasing sediment maturity and demo nstrate pervasive north-directed sediment transport interacting with a succ ession of sediment (fluvial) sources. South of the Tully River, the occurre nce of limited compositional variability indicates significant mixing on th e inner shelf. However, further north the data are highly variable, suggest ing that sediment inputs from individual rivers may be retained relatively close to source. This may be related to a greater sediment trapping efficie ncy within northern embayments and/or by lower net rates of along-shelf tra nsport.