The role of biological weathering in periglacial areas: a study of weathering rinds in south Iceland

The importance of biogeochemical processes in the morphogenic system of periglacial environments has been underestimated for decades. Weathering rind studies help to characterise and quantify biogeochemical weathering over time. Experiments using fungi strains isolated from basaltic boulders allow one to decipher biological weathering. A historical approach using heterochronous moraines provides the opportunity to follow the life of weathering rinds and helps to build a chronology of dominant processes of weathering during the first century of exposure. It appears that exfoliation of weathering rinds, commonly observed on boulders, is the result of a combination of both biogeochemical and physical processes.