Tidally Incised Valleys on Tropical Carbonate Shelves: An Example from the Northern Great Barrier Reef, Australia

Updated: 2018-04-22

The formation of incised valleys on continental shelves is generally attributed to fluvial erosion under low sea level conditions. However, there are exceptions. A multibeam sonar survey at the northern end of Australia's Great Barrier Reef, adjacent to the southern edge of the Gulf of Papua, mapped a shelf valley system up to 220 m deep that extends for more than 90 km across the continental shelf. Based on observations, we propose a new conceptual model for the formation of tidally incised shelf valleys.