Glacial erosion and paleoclimate reconstruction

• Applicant: Professor Dr. Joachim Kuhlemann
• Subject Area: Palaeontology
• Term: from 2005 to 2008
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 5445120

Investigation of glacial deposits and trimlines in Corsica enabled us to map the maximum extent of glaciers during the Würmian glaciation. Glaciers reached down to elevations of 500 m a.s.l., much deeper than documented in the literature. Moreover, two generations of pre-Würmian trimlines and roches moutonnees and few deposits prove even wider extent of glaciers. The relief was obviously modified to a higher degree than previously assumed. Glaciations appear to play a key role for the destruction of Miocene paleosurfaces. Ort the other hand, high-elevated relics of Miocene paleosurfaces display a remarkable potential for selfamplifying accumulation of large ice fields. The reconstruction of the ancient equilibrium line altitude (ELA) pattern provides important information an the regional climate during the Würmian maximum glaciation in the northwestern Mediterranean. Two preWürmian maximum glacial expansions can be locally constrained, which offer an opportunity to roughly estimate ELA-lowering and paleotemperature. A reconstruction of the Würmian ELA distribution will increase in reliability if the maximum glacier extent can be linked with one of the several short periods of glacier expansion within the Würmian glacial cycle. Thus, a robust stratigraphic framework for moraine deposits needs to be established. Therefore, we aim to determine exposure ages of large boulders rising above Würmian moraines by means of dating 10Be cosmogenic nuclides. Glaciofluvial terraces shall be dated by luminescense methods. Pre-Würmian erosional landforms shall mostly be dated by 10Be cosmogenic nuclides of erosion features. In a larger geographic frame, Corsica plays a key role for the glacial climatic setting of the western Mediterranean and Europe as a whole. High pressure in central Europe during füll glacial conditions has likely blocked eastward moving cyclons and frequently pushed them into the northwestern Mediterranean realm, where the high mountains of Corsica form an obstacle to moisture transport.

• DFG Programme: Research Grants
• Participating Person: Professor Dr. Wolfgang Frisch