Sediments in Broad Sound, Australia22S 150.3E
Broad Sound is a large bay on the east coast of Australia, in the state of Queensland 675 km northwest of the state capital, Brisbane. It is about 50 km long and 20 km across at its widest point. The Torilla Peninsula forms the eastern side of the bay; Shoalwater Bay is on the other side of the peninsula.
The bay has a low-lying coastline with wide mudflats exposed at low tide and backed by extensive areas of mangroves. Here, sediments can be seen spilling out of the sound. The head of the bay has the greatest tidal range on Australia’s east coast – around 9 m.
The coastline is punctuated by the mangrove-lined estuaries of several rivers and creeks, including Herbert and St Lawrence Creeks and the Styx River. Behind the mangroves is a hinterland of low, rounded hills covered by a mix of grassland and low eucalypt woodland or forest. The climate is subtropical with a dry winter.
The extensive tracts of mangroves and mudflats, comprising some 1200 km2 in the southern part of the bay, have been classified by BirdLife International as an Important Bird Area.