Icebergs calved from the Antarctic Ice Sheet have drifted eastwards and northwards into the southern Pacific Ocean carried by the Antarctic Circumpolar Current (ACC). Grounding of these icebergs on the seafloor of Chatham Rise, 500 km east of New Zealand, has produced distinctive linear ploughmarks and circular pits similar to those observed in other parts of the world (e.g. Kudrass & Von Rad 1984; Woodworth-Lynas et al. 1991). The 1000 km long Chatham Rise trends east–west (174° E–176° W), with a width of 250 km, from the east coast of the South Island. A crest water depth of c. 400 m is observed on a significant bathymetric high on Chatham Rise; several shallow banks and the Chatham Islands are also prominent highs. Modern shipborne and Remotely Operated Vehicle (ROV) derived multibeam bathymetric and sidescan sonar data were collected over the Chatham Rise crest, showing iceberg ploughmarks and circular pits.