Email : maxime [dot] bernard [at] univ-rennes1 [dot] fr
Phone : +33 223234415
Office number : BAT 15, P121
B. 15, Room 121, Beaulieu Campus
University of Rennes 1
35042 RENNES cedex
Geomorphological evolution of NE Greenland
The fjords of East Greenland are the widest and more pronounced fjords worldwide. Because fjords are a unequivocal morphology associated to ice erosion, they represent a fantastic archive to understand the co-evolution of ice, landscape and climate during the Cenozoic. Indeed, characterizing and dating the shaping of these fjords and of other morphological markers provides unique insights into tboth the geological evoltion of the East Greenland margin and the dynamics of the Greenland ice-sheet and its growth over time. If the age of the ice-sheet was previously inferred ranging from about 5 to 45 million years, a recent publication with new data from our group strongly supports an onset of ice at 30 million years. This timing coincides with a major worldwide climatic cooling event at to the Eocene-Oligocene transition. However, the morphology of these fjords and the amplitude of their incision since this cooling event vary spatially in a pattern that is not yet understood. Are these variations associated to the initial extent of the ice-sheet or to its dynamics, to the initial pre-glacial topography, to lithological or geomorphological variations? Answering these questions are fundamental to characterize the state and extent of the ice-sheet throughout the Cenozoic and to better constrain paleo-oceanographic –climatic and -tectonic models on the regional to global scales.
Objectives: To explore these issues I focus on:
- thermochronological analyses of existing and newly collected bedrock and detrital samples from East Greenland, using both apatite fission track analysis and (U-Th)/He dating.
- the development and application of modelling approaches to infer the temperature-time histories of the sampled rocks;
- making a quantitative analysis of East Greenland landscape geomorphology to characterize the links between fjord morphology, exhumation history, climate change, and other environmental factors;
- the investigation of the evolution of fjords and landscapes on the border of a dynamic ice-sheet using the iSOSIA landscape evolution numerical model. This will involve some time working with colleagures from the University of Aarhus, Denmark.