Abstract
Three dredge hauls were recovered from scarps on the West Greenland continental shelf in Baffin Bay. Two of the dredge hauls consisted essentially of basalts but the third, at the mouth of Disko Bay, contained some 50% Precambrian erratics. Both the mineralogy and chemistry of these offshore rocks are very similar to the most evolved basaltic compositions found elsewhere in the West Greenland Tertiary volcanic province. The dredged samples show none of the features expected for submarine tholeiites and were therefore probably erupted subaerially and later subsided below present day sea-level. A petrogenetic model, involving equilibration of a basaltic magma at a pressure in the range 5–8 kb, is proposed to account for the chemistry of this suite of rocks.