Fig. 3.

Examples of buried linear and curvilinear incisions interpreted as iceberg ploughmarks in the study area. a. Structure amplitude map of ploughed palaeo-surface T1 (3D seismic cube ST9301). b. Part of seismic cube ST9301 (Inline 2819) showing an example of cross-sectional image of buried ploughmark on a 2D seismic line. c. Linear double-keeled ploughmarks produced by large tabular icebergs (found on the palaeo-slope surface within the Naust S sequence). d. Curvilinear semi-spiral iceberg ploughmark present on the early – middle Quaternary palaeo-surface A0 (occurrence of such features within the Naust Formation is rare compared to regular linear cross-cutting keels) e. Example of spiral-keeled ploughmarks found on the modern seafloor (occurrence of such features is relatively rare).