This is MV’s specialty, so if I get it wrong, sorry.
A research team from James Cook University has found zircon crystals in Vanuatu of the same age as zircons in Australia (about 3BY), raising questions about how continents are formed. The zircons were apparently carried from Australia in magma.
http://www.bbc.com/news/world-australia-29797137
Their paper adds weight to a solution for some problems that have been floating around geology: how do island arc magmas develop their unique geochemical signature; and why are some island arcs are less dense than expected.
The answer is likely that they contain tiny fragments of continents, but this has been difficult to demonstrate.
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Buys, Janrich, Spandler, Carl, Holm, Robert J., and Richards, Simon W. (2014)
Remnants of ancient Australia in Vanuatu: Implications for crustal evolution in island arcs and tectonic development of the southwest Pacific.
Geology. pp. 1-4. (In Press)
http://dx.doi.org/10.1130/G36155.1
http://geology.gsapubs.org/content/early/2014/09/15/G36155.1
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Abstract:
We report new geochemical and geochronological data on igneous rocks of the little-studied Western Belt of the Vanuatu intra-oceanic arc. Ar-Ar dating of igneous hornblende from hornblende andesites and U-Pb dating of zircon from a tonalite place formation of these rocks in the late Eocene to Miocene; hence, they represent part of the earliest arc development at Vanuatu. The petrological and geochemical characteristics of these rocks are typical of island arc magmas, except they contain inherited zircon grains with significant age populations at ca. 2.8–2.5 Ga, 2.0–1.8 Ga, 1.75–1.5 Ga, 850–700 Ma, 530–430 Ma, and 330–220 Ma.
This inheritance signature is unlike anything recognized from the oceanic realm of the southwest Pacific, but in general does match the age of major crustal blocks of the Australian continent. An exception is the significant proportion of zircons of Rodinia breakup age (ca. 800 Ma) that previously have not be found in such amounts in eastern Australia or the southwest Pacific. We propose that part of the Vanuatu arc basement comprises continental material that was rifted and transported thousands of kilometers from northeastern Australia prior to the Cenozoic.
The presence of hitherto-unrecognized ancient continental material within an intra-oceanic arc provides an alternative source for the crustal trace element and isotopic signature of island-arc magmas, and may help reconcile the relatively large thickness and low density of the crust of Vanuatu and possible other intra-oceanic arcs.