Major Australian-Antarctic plate reorganization at Hawaiian-Emperor bend time.
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.
Whittaker
J M
JM
EarthByte Group, School of Geosciences, University of Sydney, Sydney 2006, Australia. j.whittaker@geosci.usyd.edu.au
Müller
R D
RD
Leitchenkov
G
G
Stagg
H
H
Sdrolias
M
M
Gaina
C
C
Goncharov
A
A