Analysis of wire line logs at Ocean Drilling Program Site 642, the deepest scientific hole yet drilled in an offshore large igneous province (LIP), reveals the main features of the extrusive complex constructed during formation of a volcanic margin. A characteristic cyclic log response images tholeiitic lavas and thin tuffs corresponding to the seaward dipping reflectors in the seismic record. Flows are 0.6--18.5 m thick, while most sediments are 2000 &OHgr;-m, focused resistivity kicks. The large flow-scale variations in physical properties show that representative core measurements must be densely sampled. Both on flow and sequence scales Site 642 log responses appears typical for the North Atlantic Volcanic Province and other LIPs but differs from logs in deep ocean crustal holes. Principal differences in log responses reflect mode of crustal emplacement and alteration. Hence Site 642 forms a reference hole for extrusive constructions on oceanic LIPs. ¿ American Geophysical Union 1994