Analysis of Pomeranian erratics suitability for the study of the last Scandinavian Ice Sheet recession with cosmogenic nuclides

https://doi.org/10.26485/AGL/2017/106/14

Abstract

_{Large erratic boulders located in situ on moraines may be a target for surface exposure age dating with TCN (Terrestrial Cosmogenic Nuclides ). This paper presents the method and the results of the selection of erratics in Pomerania for this type of dating. Middle and eastern Pomerania are key regions to complete the cosmogenic chronologies of the geomorphology left by the last Scandinavian Ice Sheet retreat in the northern Polish landscape. Our selection of massive erratics consists of two stages. First, a GIS database (254 erratics) was constructed based on all available information about large boulders, and erratics were selected based on their dimensions and distribution against a digital elevation model and geologic maps. Second, field inspection of preliminarily selected boulders was conducted and 27 erratics were finally selected as suitable for surface exposure age dating with TCN. The significant reduction of the number of boulders at particular stages of qualification shows the importance of the proposed systematic selection. Spatial distribution of the selected boulders (location on moraine plateaux and paleo ice-marginal belts) and their individual features show their high usefulness for surface exposure age dating with TCN.}