Glacial landscape and morphometric analyses for the reconstruction of Cenozoic glacial history in northern Victoria Land.

A well-developed alpine topography characterizes the valley system of northern Victoria Land (NVL). It was sculpted since the Eocene-Oligocene boundary on an inherited network of sinuous valleys with typical dendritic pattern of fluvial origin. Landscape analysis, conducted in the framework of the Italian Antarctic Research Program, provided detailed information on geomorphologic features and on processes responsible for their evolution. Three geomorphological and glaciological maps at the scale of 1:250.000 have been realized. Research so far conducted allowed us to reconstruct the most relevant Cenozoic phases of landscape evolution, denudation sequences and variations in glacial dynamics. Morphometric parameters from glacial valley cross profiles provided mathematical characterisation of valley troughs. Temperate glaciers were responsible for denudation until the Late Miocene. Host glaciers presently flow in inherited alpine troughs, nest in relict glacial cirques, and flow from top and intermediate flat surfaces. Like a white glass, snowfields and glaciers simply mantle the relict topography. Glacial erosion is negligible since Late Miocene. The East Antarctic Ice Sheet has never influenced the NVL glacial system, in their post fluvial evolution.