1.1.3.4 Basin connectivity

As the Sydney Basin developed in conjunction with other basins to the north, some connectivity would be expected to the north, with the Gunnedah Basin, which in turn is connected to the more northern Bowen Basin. However, shallow basement at the Mount Coricudgy Anticline is believed to divide the Sydney and Gunnedah basins, and may form a structural boundary (Danis et al., 2011, p. 536; Bembrick et al., 1980, p. 2). Nevertheless, rocks typical of the northern Sydney Basin are present north of the anticline (NSW DTI, n.d.) suggesting that some connection remains. Additionally, Danis et al. (2011, p. 541) stated that sedimentary thickness is around 1.5 km over the Mount Coricudgy Anticline and the Western Coalfields, near the boundary with the Gunnedah Basin, reinforcing that significant sedimentary connection may exist, albeit less thick than elsewhere in the Sydney-Gunnedah Basin (O’Neill and Danis 2013, p. 19). The Sydney Basin is otherwise laterally constrained; to the west it is bounded by the older basement rocks of the Lachlan Fold Belt, to the north-east by the New England Fold Belt and to the east and south where the basin extends to the edge of the continental shelf.