Abstract Details
| ID: | 144 |
| Title: | Late-Holocene glacier variation in the Southern Alps of New Zealand - with special emphasis on geomorphological uncertainties and inter-hemispheric comparison |
| Content: | The Southern Alps of New Zealand are among the key areas for the investigation of Holocene glacier chronologies, especially because of the lack of mid-latitude mountain regions in the Southern Hemisphere. Although a number of glacier chronologies have been published during the last decades, the Holocene glacier records remains rather inconclusive with partly controversial results. Due to their location at an active plate boundary with high potential for major impacts of climate-and/or tectonic-related geomorphological events, dating moraines and related landforms in the Southern Alps always bears certain uncertainties. Results from various glaciers in the Southern Alps using a "multi-proxy approach" of Schmidt-hammer exposure-age dating (SHD) combined with terrestrial cosmogenic-nuclide dating (TCND) will be presented. These two techniques are logically combined to enable mutual testing and to construct age-calibration curves. At least three Late-Holocene (Neoglacial) "Little Ice Age"-type events predating the "Little Ice Age" have been clearly detected. The patterns of this Late-Holocene glacier chronology correspond relatively good with glacier variations in maritime South Norway, as do the more recent glacier variations during the 20th century. It will be argued that much of the controversy between existing studies on the New Zealand glacier chronology emerges from the abovementioned regionally specific geomorphological environment and the related uncertainties with the application of different dating techniques. By contrast to other recent studies, it will be demonstrated that the New Zealand glacier chronology does in fact correspond to some extent to some chronologies in the Northern Hemisphere. The previously suggested high number of major glacier advances obviously needs to be adjusted by taking realistic uncertainties with moraine dating into account. |
| Session: | 15 Holocene Glacier Variability from the Tropics to the Poles |
| Authors: |
Stefan Winkler |
| Presenter: | Stefan Winkler |
| Type: | oral |
