Tasman blowhole

'It is called the tessellated pavement. The pavement appears tessellated (it's tiled) because the rocks forming it were fractured by earth movements. The fractures are in three sets, one set runs almost north, another east north east, and a third discontinuous set north north west. These last two sets produce the tiled appearance. The flatness of the pavement is due to initial erosion by waves carrying sand and gravel and nearer to the cliff, to chemical action by sea water. The rocks which absorb sea water during high tide dry out during low tide causing salt crystals to grow and disintegrate the rocks - a process which produces shallow basins'. The placard notes that the information has been provided by the Geology Department of the University of Tasmania.