Moraines of the upper rakaia valley

Abstract

Moraines in the Upper Rakaia Valley record glacial activity at intervals between about 12,000 yr BP and the last few decades. The Lake Stream and Jagged Stream advances occurred probably between 11,900 and 10,000 yr BP and extended 29 km and 21 km, respectively, from the valley head. One or more renewed advances occurred more than 4,500 yr BP and gave rise to the complex of drift near the Reischek River only 9 km from the valley head. Another phase of glacial activity began 4,500 yr BP (at least) and constructed moraines on the Meins Knob ridge, but no date is available for its end. Further advances formed a complex of moraines near the Lyell Hut more than 1,000 years ago. The most recent series of glacial events formed the Whitcombe group of moraines within the last few centuries.