Interglacial vegetation in South Westland, South Island, New Zealand

Abstract

Two pollfen diagrams derived from organic sediments at the northern and southern ends of Greens Beach, north of Lake Ianthe, South Westland, New Zealand, are discussed. The sediments overlie till of the penultimate glaciation (Waimean Glacial) and at the southern site are buried beneath c. 12 m of fluvioglacial gravels of last glacial (Otiran Glacial) origin; at the northern site, the peats are overlain by silt, probably overbank deposits, and loess. The pollen diagrams reflect mostly events of the last interglacial (Kaihinu). Although both diagrams represent the same phase of the interglacial, similarities are not immediately apparent because of breaks in the pollen record from the northern (Opuku) site. Two radiocarbon dates, one from mid section (NZ4379A, 29 600 ± 850 ¹⁴C yr BP) and one from nearer the base (NZ4378A, 38 000 + 4450 ‐2850 ¹⁴C yr BP), provide a mid‐Otiran age for the site. Because the pollen diagrams reflect interglacial conditions, and because of the stratigraphic position of the organic sediments, the dates are rejected as being too young.

Keywords:

• pollen diagrams
• Greens Beach
• South Westland
• Kaihinu Interglacial
• Otiran Glacial