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Almost 90% of 39 m of core material recovered from Scoresby Sund and the adjacent East Greenland shelf is massive diamicton, interpreted to be formed predominantly by the release of iceberg rafted debris and reworking by iceberg scouring. There is also likely to be a contribution from suspension settling of fines derived from glaciofluvial sources. Model calculations suggest that the 14C derived Holocene sedimentation rate of 0.1‐0.3 m 1000 yr−1 in Scoresby Sund can be accounted for mainly by iceberg rafting of debris. A further 4% of core material is of gravel or coarse sand lenses, interpreted to reflect iceberg dumping of debris. Intensive iceberg scouring, which reworks sea floor sediments, is observed on acoustic records from over 30 000 km2 of the Scoresby Sund fiord system and the adjacent East Greenland shelf (69‐72°N and 75°N). The rate of iceberg production from Greenland Ice Sheet outlet glaciers, and iceberg drift tracks on the shelf, suggests that iceberg rafting and scouring may be important over a significant proportion of the 500 000 km2 area above the shelf break. The relatively extensive modern occurrence of massive diamicton, formed by iceberg rafting and scouring, together with suspension settling of fines, suggests that it may also be a significant facies in the glacier‐influenced geological record. The recognition in the geological record of the massive diamicton facies described above may also indicate the former presence of fast flowing ice sheet outlet glaciers.

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The Scoresby Sund fjord system, East Greenland, contains the most productive fast‐flowing outlet glaciers draining east from the Greenland Ice Sheet, calving 18 km3 a−1 of icebergs. The sizes, frequencies, and freeboards of 1900 icebergs were measured from F.S. Polarstern, using ship X‐band radar and sextant. Radar beam spreading exaggerates iceberg width by 60 m per nautical mile of range beyond the first mile. Data sets on iceberg size (e.g., that collated for Antarctic icebergs) collected using ship radars which do not take this effect into account will overestimate iceberg dimensions significantly. The location and concentration of icebergs within the fjord complex can be explained by (1) the locations of the principal source glaciers and (2) fjord topography and bathymetry. Iceberg concentration (maximum 0.6 icebergs km−2) declines with distance from the major iceberg sources. We found that 69% of icebergs within the fjord system are <200 m in width. Only five are >1 km in length. The largest is 2.7 km long. Icebergs become spread more evenly over the range of size classes in the outer fjord and shelf. Modal iceberg keel depth, calculated from freeboard measurements, is 4–500 m in the inner fjords, shifting to lower values in the outer fjords, reflecting shallower bathymetry. Radar measurements of iceberg width cannot be used to infer keel depths accurately, because width and keel depth are only weakly correlated. Comparison between freeboards and keel depths for icebergs from East Greenland and the Barents Sea indicates that the iceberg source (i.e., floating or grounded) exerts a fundamental control on iceberg dimensions. The drift pattern of icebergs is from the head to the mouth of the fjord system, although fjord bifurcations, bathymetry, and currents provide additional complications. The trends in observed iceberg size and frequency, and in inferred keel depth, in the Scoresby Sund region are likely to be applicable to other fjords and shelves around Greenland.