Post-rift flood-basalt-like volcanism on the Newfoundland Basin nonvolcanic margin: The U event mapped with spectral decomposition

► Diabase sills in the Newfoundland Basin cover an areal extent of about 20,000 km2. ► The volume of magma in the sills is at least 1000 km3 but could be more than 2000 km3.► The sills are generally thicker in the southern Newfoundland Basin.► The source of the sills can be related to the Canary and Madeira hot spots.