What's in a name? The Columbia (Paleopangaea/Nuna) supercontinent

Supercontinents play an important role in Earth's history. The exact definition of what constitutes a supercontinent is difficult to establish. Here the argument is made, using Pangaea as a model, that any supercontinent should include similar to 75% of the preserved continental crust relevant to the time of maximum packing. As an example, Rodinia reached maximum packing at about 1.0 Ga and therefore should include 75% of all continental crust older than 1.0 Ga. In attempting to 'name' any supercontinent, there is a clear precedent for models that provide a name along with a testable reconstruction within a reasonable temporal framework. Both Pangaea and Rodinia are near universally accepted names for the late Paleozoic and Neoproterozoic supercontinent respectively; however, there is a recent push to change the Paleo-Mesoproterozoic supercontinent moniker from Columbia to Nuna. A careful examination of the Nuna and Columbia proposals reveals that although the term Nuna was published prior to Columbia, the Nuna proposal is a bit nebulous in terms of the constitution of the giant continent. Details of Nuna given in the original manuscript appear to be principally based on previously published connections between Laurentia, Baltica and, to a lesser extent the Angara craton of Siberia (i.e. the lands bordering the northern oceans). Therefore the proposal is made that Columbia consists of several core elements one of which is Nuna. (C) 2011 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved.