K'gari is anoutstanding example of significant ongoing geological processes including longshore drift.

There is evidence that deposition has occurred through processes operating over the last 540,000 to 750,000 years making it an area with one of the longest periods of coastal dunefield evolution in the world.

Active parabolic dunes (sometimes called 'blowout')are superimposed on remnants of older dunes which were deposited during periods of low sea level. These older dunes are stabilised by towering rainforests.

The Island also has a variety of freshwater dune lakes. The interrelationship between the coastal dune sand mass, aquifer hydrology and the freshwater dune lakes provides a sequence of lake formation across the Island over time.

A variety of soils have developed on these dunes. These differences have strongly affected the types of vegetation communities that have subsequently developed. The soils of K'gari are very deep (up to 25m) and this is one of the reasons that the Island was listed on World Heritage.

Coloured sands

The Island's famous coloured sands are found on the eastern beach, north of Eli Creek.

The colours are created by the leaching of oxides and the decay of vegetation. The yellows, browns and reds are created by iron-rich minerals in the dune sands. The sands are particularly stunningat Rainbow Gorge, the Cathedrals, Red Canyon and The Pinnacles.

More information: Miot da Silva, G., and Shulmeister, J. (2016). A review of coastal dunefield evolution in Southeastern Queensland. Journal of Coastal Research, Vol. 75, pp. 308-312.