Major Australian-Antarctic Plate Reorganization at Hawaiian-Emperor Bend Time

• Published in: Science
• Main Authors: Whittaker, J. M., Müller, R. D., Leitchenkov, G., Stagg, H., Sdrolias, M., Gaina, C., Goncharov, A.
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Association for the Advancement of Science (AAAS) 2007
• Subjects: Antarctic; Emperor Seamount Chain; Pacific; Tonga; West Antarctica; Antarc*; Antarctica
• Online Access: http://dx.doi.org/10.1126/science.1143769; https://www.science.org/doi/pdf/10.1126/science.1143769

A marked bend in the Hawaiian-Emperor seamount chain supposedly resulted from a recent major reorganization of the plate-mantle system there 50 million years ago. Although alternative mantle-driven and plate-shifting hypotheses have been proposed, no contemporaneous circum-Pacific plate events have been identified. We report reconstructions for Australia and Antarctica that reveal a major plate reorganization between 50 and 53 million years ago. Revised Pacific Ocean sea-floor reconstructions suggest that subduction of the Pacific-Izanagi spreading ridge and subsequent Marianas/Tonga-Kermadec subduction initiation may have been the ultimate causes of these events. Thus, these plate reconstructions solve long-standing continental fit problems and improve constraints on the motion between East and West Antarctica and global plate circuit closure.