Carbonate platform growth, demise and sea level record : Marion Plateau, Northeast Australia

Abstract

The Marion Plateau located between 18°S and approximately 23°S in the area beyond the Great Barrier Reef offshore between Gladstone and Townsville is the most southerly of the marginal plateaus in northeastern Australia. It forms a deeper extension of the Queensland continental shelf with water depths ranging from 100m along its south western margin to 500m along the northern and eastern margins. The plateau is bound along its northern margin by the Townsville Trough; by the Cato Trough along the eastern margin; and the central Great Barrier Reef to the south west. Modern reef development on the Marion Plateau is confined to Marion Reef in the north and Saumarez Reef in the south. The plateau is part of a slowly subsiding upper plate margin and the plateau summit remained exposed throughout the Palaeogene during which time it was planated to form a gently dipping relatively smooth plateau summit with a maximum width of 200 km.