9416631 Holbrook A joint US-Danish study of the Southeast Greenland margin to provide a better understanding of the volcanic rifted continental margins which contain great thicknesses of mafic igneous material emplaced during continental breakup. This is an ideal setting to study volcanic rifted margins, because of a known hotspot and well defined hot spot track, a relatively simple tectonic and geologic history and a thin postrift sediment cover. Recent ODP drilling and numerous existing field studies provide additional background data. A multichannel and wide-angle seismic study in planned with the objectives to determine the influence of a mantle plume on the rifted margin magmatism, the detailed structure of the continent- ocean transition, and to compare the crustal structure of conjugate volcanic margin segments. The data will provide a framework for interpreting geological and drilling results on the margin and for constraining thermomechanical models of volcanic rifted margin evolution.