The nature of Mawsonites (Ediacara fauna)

Some representatives of the Ediacara fauna have been later re-interpreted as pseudofossils. This was recently also done for Mawsonites, which was re-interpreted as a sedimentary structure formed due to interaction of a sand volcano (or water-escape structure) and a biomat. This sedimentary genesis appears not to be tenable, as several physical processes should have been involved, none of which is known from modem times or the geological past. It is concluded that Mawsonites must be considered as a fossil, either an imprint or a true fossil. This interpretation may be tested on one or more fragments of the structure. (C) 2007 Published by Elsevier B.V. on behalf of International Association for Gondwana Research.