We analyzed the morphology of the D2 subglacial lake in Antarctica using 2021/22 seismic data. The ice–lake boundary is well identified, but there is ambiguity about the presence of a sediment layer at the lake bottom (Scenario 1: no sediment; Scenario 2: with sediment). Both scenarios were modeled and compared with field data. Estimated depth is approximately 53–82 m (model 1) or approximately 10 m (model 2). The quantified structure will help pick future drill sites.