Rock glaciers evolution in Late Glacial and Holocene inferred from the new palaeoclimatic data

Abstract

Rock glaciers are landforms made of mountain permafrost creeping under the effect of gravity and characterized by a particular topography of ridges and furrows ended with a steep front. By decoding their present morphology and understanding their altitudinal distribution, a variety of aspects of the past climatic conditions can be inferred because inactive and relict rock glaciers are located in warmer climates in comparison to their necessary morphogenetic conditions (Frauenfelder and Kaab 2000). Most of the rock glaciers from SC are of small dimensions (0.05km2), they have a faded morphology and are covered in different proportions with soil and vegetation indicating their inactive or relict state, characteristic to the marginal permafrost conditions of Southern Carpathians. That is because most of the rock glaciers are located in positive mean multiannual air temperatures. Several field studies performed in the last decade indicate that permafrost is present in rock glaciers above 1950 m a.s.l. in the highest massifs of SC, with a relatively more widespread distribution in the granitic massifs (Vespremeanu-Stroe et al., 2012; Onaca et al., 2013; Popescu et al., 2015; Onaca et al., 2015)