The main objective of GPR data processing and interpretation is to select a velocity model of the media to transform time-section into depth-section. The modeling results serve to identify revealed layers with geological or glaciological objects. The paper describes an algorithm for calculating hodographs of diffracted wave realized in modeling a medium with inclined layers to construct appropriate velocity model. The efficiency of the described algorithm is illustrated by the GPR data collected during the austral summer field season of the 60th Russian Antarctic Expedition (2014/15) in the Mirny Station area, East Antarctica.