Mildenhall, D.C. 1999 Pollen analysis of the Plio-Pleistocene Kowai Formation (Kurow Group), Mackenzie Basin, Central Otago. Lower Hutt: Institute of Geological & Nuclear Sciences. Institute of Geological & Nuclear Sciences science report 99/17 23 p.
Abstract: The Kowai formation in the Lake Pukaki area is a tectonically deformed gravel sequence containing rare fossiliferous fine-grained horizons with pollen assemblages that are unusual in their composition. The age of the beds is Pliocene, as determined by the presence of a number of pollen species that last appeared in the Pliocene, along with a few taxa that first appear at the same time. During the early phases of deposition the climate was warmer and more humid than the present day as evidenced by the presence of abundant araucarian, Nothofagus (Brassopora) beech and Casuarina pollen. Most of the Kowai Formation was deposited at a time when the area was covered in a Nothofagus (Fuscopora) beech forest, indicative of a climate not dissimilar from that experienced in present day beech forests. At the top of the sequence glacial conditions started appearing as the forest vegetation disappeared to be replaced by grassland/scrubland vegetation. (auth)