Valley cross‐profile morphology and glaciation in park valley, tararua range, new zealand

Abstract

Previous anecdotal research by G. L. Adkin over 90 years ago suggested that Park Valley in the Tararua Range was glaciated during the Late Quaternary, on the basis of the “U‐shaped” cross‐profile character of the uppermost parts of the valley. We quantitatively describe the cross‐profile morphology of the upper parts of Park Valley in the Tararua Range, using the power‐law model (y = axb) and the form ratio model (FR = D/2W). Comparison of these results with morphological data published in global studies of glaciated landscapes suggests the upper parts of Park Valley have indeed been glaciated. Palaeoglacier reconstruction of this area gives a surface area of c. 1.41 km2, a maximum thickness of 130 m and a maximum basal shear stress value of 99 kPa. The equilibrium‐line altitude of the former glacier has been calculated as c. 1210 m, and with the absence of any dated moraines, the glacier is assumed to have formed during the Otira Glaciation. © 2005 Taylor & Francis Group, Ltd.