Rodinian detrital zircons in Late Cretaceous sandstones indicate a possible Precambrian basement under Southern Zealandia

U-Pb ages of detrital zircons in Late Cretaceous sandstones overlying Paleozoic basement in southernmost Zealandia have unusually high proportions (40%) of Precambrian zircons, mostly Mesoproterozoic (ca. 1100. Ma) and Neoproterozoic (ca. 800. Ma). The proportion of Precambrian (Rodinia), relative t...

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Bibliographic Details
Published in:Precambrian Research
Main Authors: Adams, C. J., Griffin, W. L.
Format: Article in Journal/Newspaper
Language:English
Published: 2012
Subjects:
Online Access:https://researchers.mq.edu.au/en/publications/53c262b5-64a2-4e97-92a8-d3f24bb0ee77
https://doi.org/10.1016/j.precamres.2012.04.003
http://www.scopus.com/inward/record.url?scp=84861208616&partnerID=8YFLogxK
Description
Summary:U-Pb ages of detrital zircons in Late Cretaceous sandstones overlying Paleozoic basement in southernmost Zealandia have unusually high proportions (40%) of Precambrian zircons, mostly Mesoproterozoic (ca. 1100. Ma) and Neoproterozoic (ca. 800. Ma). The proportion of Precambrian (Rodinia), relative to early Paleozoic (Gondwana), zircon groups is anomalously high and the former cannot have been reworked from any known basement rocks within Zealandia. Since Late Cretaceous sandstones were deposited after the breakup of Gondwana, it is proposed that their Precambrian zircons originated in Precambrian basement within Zealandia, briefly exposed along its Australian/Antarctic margin during Gondwana breakup. The ca. 1100. Ma and ca. 800. Ma age components suggest a former juxtaposition against the South China Block, when Zealandia was located east of Australia in Meso- and Neoproterozoic time.