Antarctica‘s continent-ocean transitions: consequences for tectonic reconstructions

Early opening of Australia and Antarctica: New inferences and regional consequences

“…Using this interpretation, he dates the breakup at 95+-5 Ma. Veevers's (1986) COB for the South Australian margin and its Antarctic conjugate delineated from seismic data by Colwell et al (2006) has been used in many subsequent works (Direen et al, 2011;Espurt et al, 2009;Gohl, 2007;O'Brien and Stagg, 2007;Powell et al, 1988;Stagg and Reading, 2007;Veevers and Li, 1991;Williams et al, 2011). A revised interpretation of the COB was proposed by Ball et al (2013) who moves it~100 km-further oceanward.…”

Restoring the continent-ocean boundary: constraints from lithospheric stretching grids and tectonic reconstructions

“…Accurate reconstruction of stretched continental crust, as well as transitional and oceanic crust, is crucial for reconstructing accurate paleo-bathymetries, paleo-geographies and paleoocean circulation modes as the nature of the crust on the Australian-Antarctic margins may produce considerable differences in the width and depths of gateways for paleoocean currents [Gohl, 2008].…”

Antarctic palaeotopography

“…A recent attempt to restore Antarctic margin palaeotopography (since ca. 34 Ma) for the effects of residual post-rift cooling (Paxman et al, 2019b) adopted a 1D cooling model (McKenzie, 1978) (Equation 3) using the observed age of the sea floor (Müller et al, 2016) and a uniform β value of 4 across the widths of the continent-ocean transitions around Antarctica (Gohl, 2008). The modelled magnitude of post-Eocene thermal subsidence around the margins of East Antarctica varies from ~300 m for the earliest-formed continental shelves (e.g.…”