The Geology of Shark Bay
Shark Bay World Heritage Area covers more than 2.2 million hectares and has a coastline more than 1,500 km long. It features landscapes and seascapes both colourful and diverse, from red cliffs and turquoise lagoons to salty depressions and giant dunes. This geology is simultaneously ancient and modern, the result of ongoing interactions between wind and sea, plants and animals, and the Earth’s tectonic forces. These complex connections mean that Shark Bay is not ‘set in stone’, but a place of living change.
Shark Bay’s exceptional scenery contributed to its World Heritage listing. Its contrasting red and white sandstones are evident in its sweeping beaches, rocky headlands, peninsulas and prongs. Peron Peninsula in the east has rolling red sand hills interspersed with strange salty hollows, known as birridas. The white dunes and rocky outcrops of Edel Land, in the west, end abruptly where the Zuytdorp Cliffs plunge into the sea.
Shark Bay’s geology is ever-changing. Land that was dry during the last ice age is now flooded, and seagrasses grow where wallabies once roamed. Sediments trapped by seagrass meadows have created underwater barriers, affecting the sea’s salinity, tidal flow and ecosystem. The influence of these plants on the geology, chemistry and biology of Shark Bay is a World Heritage value. Learn more about the processes that shaped Shark Bay here.