The Eastern Plateau lies midway between Queensland and Papua New Guinea and is the northernmost marginal plateau of the northeast Australian continental margin. The plateau has a gently convex surface and covers an area of about 31,000 km2 (Davies, 1989). There is one site of active reef growth, Eastern Fields Reef, on the northern margin of the Plateau, with submerged and buried reefs extending northeast from this area into the Moresby Trough (Isern, 1997).
The Eastern Plateau is bound to the north by the Moresby and Pandora Troughs, to the west by the Bligh Trough, to the south by the Osprey Embayment and to the east by the Moresby Canyon and the Coral Sea Basin (Davies, 1991). The northern and southern plateau margins are controlled by normal faults and the western margin has been highly deformed by thrusts and wrench faulting. The eastern margin of the plateau has been deformed by collision with the terranes of the Papuan Peninsula (Davies, 1991 and Pigram, 1993). As the plateau is surrounded by troughs, it is generally free of terrigenous sediments (Isern, 1997).
The Eastern Plateau is underlain by deformed, fault-bounded and tilted basement blocks of approximately Late Cretaceous age (Pigram, 1993). Eocene sediments were deposited on the eroded surface of the basement blocks, onlaping onto basement highs and are commonly disturbed by faulting. The remaining sediments on the Eastern Plateau are a mix of Miocene to Recent calcareous ooze and periplatform detritus (Pigram, 1993 and Isern, 1997).