Provenance analysis of Cambrian conglomerates, Northern Victoria Land

The Cambrian volcanic arc of North Victoria Land and the Cambrian arc of NW Nelson (NZ) are strikingly similar. They are of island arc character but both now lie within continental crust. In NVL the volcanic arc is adjacent to granites of a continental margin arc of similar age. Four hypothesis can be tested:
a) The Bowers arc changed in character along its length and the two parts were subsequently tectonically juxtaposed;
b) the granitic boulders found in the North Victoria Land Cambrian arcs are not typical of oceanic arc rocks, but are derived from the Wilson terrane or older granite belts to the west, in which case the conglomerates date the amalgamation of the oceanic arc with the continental margin;
c) there were two discrete subduction zones and two separate arc systems that later amalgamated; similarities to New Zealand are coincidental.
The Carryer Glacier which has well exposed Cambrian conglomerates was visited during the first season of the investigation. In the second season, the compositionally similar conglomerate on Reilly Ridge, the north-eastern margin of the Lanterman Range where it is interbedded with fossiliferous Middle to Late Cambrian rocks was investigated together with the Husky conglomerate. The latter conglomerate is probably older.The sedimentology of the conglomerates was studied, samples of boulders were taken for integrated petrological geochemical and geochronological analysis and the ages and tectonic settings of the conglomerates components was determined. Detailed measuring of seven sections, statistical counts, structural mapping and collecting material was all accomplished. Dating of zircons within the rocks was by the U-Pb method. The data was used to accept or reject one or both of the hypotheses and the results were compared with New Zealand and Australia.