Reconstruction of pre-breakup Paleozoic-suture of Gondowana continent in Australia

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The early two months of this academic year were the season for field work in New Zealand and New Caledonia. Through the field work, we recognized the south-eastern extension of the Lachlan Fold Belt, eastern Australia in the area of the west coast in New Zealand. The extension of the New England Fold Belt, however, was, not positively recognized in New Zealand. Lithologically those of basement in New Caledonia were similar to those of the New England Fold Belt. Even so, Dating study did not support the correlation mentioned above.Ar-Ar and K-Ar dating studies for the Onekaka schist, Nelson, New Zealand were keys to solve Paleozoic metamorphism which was recognized in the New England Fold Belt. The Cretaceous ages (about 100Ma) for the Onekaka schist reveals that the early Paleozoic terrain in New Zealand has suffered only Cretaceous igneous episodes.Ar-Ar dating for the rock in Antarctica also show the same episodes. Whole rock Rb-Sr age study and Eclogite K-Ar age study also show the carboniferous activity in southern New England Fold Belt. Radiolarian study in the Lachlan and other dating studies including U-Pb isotope studies indicate the first subdution and subsequence episodes in Paleo-Pacific Ocean.