Fig. 1

a Overview of the study area in Switzerland. The box is the Twannberg area shown in detail in Fig. 2 with meteorite find locations. The red line corresponds to the profile shown in Fig. 7. Maximum Alpine ice extent (Bickel et al., 2015, blue line) and LGM (Schlüchter, 2009, blue area) are shown for reference. Red squares are exposure-dated pre-LGM boulders. b The Twannberg area with meteorite finds (blue dots) and extent of LGM ice (light blue area). Yellow symbols show distribution of pre-LGM glacially transported Alpine material (areas = till, large circles = boulders, small circles = clasts). LGM ice limit based on Schlüchter (2009) and Aufranc and Burkhalter (2017). Square symbols indicate the locations of dated samples