Extended Data Fig. 2: Coast-orthogonal radar profiles crossing the flat surfaces.
From: Extensive fluvial surfaces at the East Antarctic margin have modulated ice-sheet evolution
(a) Bed elevation of the study area (as shown in Fig. 1a). (b) Elevation-corrected radargram from the 2012 ICECAP survey15 (profile B-B’). (c) Elevation-corrected radargram from the 2011 ICECAP survey15 (profile C-C’). (d) Elevation-corrected radargram from the 2019 Operation IceBridge survey25 (profile D-D’). The profiles show the transition from the low-relief flat surfaces to the higher, rougher topography on their inland side (inland edges of the flat surfaces are marked by the red arrows). In each radargram, the solid line marks the ice surface; the major reflector below is the bed topography. Elevations are relative to the WGS84 ellipsoid. Flight line ID numbers are labelled.
