Australian-Antarctic rifting

• Main Authors: Whittaker, J, Muller, RD, Goncharov, A
• Format: Conference Object
• Language: English
• Published: RESolutions Resource & Energy Services Pty Ltd 2008
• Subjects: Earth Sciences; Geology; Marine Geoscience; Antarctic; Antarc*; Newfoundland
• Online Access: http://www.earthbyte.org/people/dietmar/Pdf/Whittaker_etal_Aus_Ant_rifting_EABS2008.pdf; http://ecite.utas.edu.au/84452

Rifting between Australia and Antarctic began as early as 140MM years ago. However, the timing of continental breakup and themanner in which rifting proceeded have remained controversial.A major reason for the ambiguity surrounding the Australian-Antarctic breakup and early spreading history is the lack of aclear boundary between continental and oceanic crust. Instead of asharp boundary there is a zone of transitional crust, up to 120 kmin width, along the entire conjugate southern Australian and eastAntarctic margins (Sayers et al. 2001). The presence of wide zonesof so-called transitional crustal on conjugate rifted Australian-Antarctic margins have resulted in considerable scientifi c debateregarding the nature of the transitional crust. Here we assessthe ability of available data to discriminate between differenthypotheses regarding the nature of the crust of the Australian-Antarctic conjugate transition zones. We also assess the suitabilityof applying depth-dependent rifting models recently developed forthe well-studied Iberian-Newfoundland conjugate margins to theAustralian-Antarctic context in order to resolve the nature of thetransitional crust and the manner in which it formed.