Figure 23. Schematic diagram showing inferred surface-water circulation of the Australian Antarctic region during the middle Eocene (43.7 Ma) with the Tasmanian Gateway closed. Plate tectonic reconstruction is modified from Cande et al. (2000). Note the influence of the East Australian Current on the Antarctic margin in the absence of circum-Antarctic circulation. Weak gyral circulation is inferred in the highly restricted Australo-Antarctic Gulf. ODP Leg 189 and DSDP Leg 29 site locations are indicated.