Understanding the tectonic framework across the West Antarctic Rift system is critical for deciphering the evolution of the Pacific margin of Gondwana; for understanding the characteristics of wide and narrow modes of continental extension; and for determining the geological controls on the dynamics of the West Antarctic ice sheet, the globe's last great "marine" ice sheet. This Award supports and integrated geophysical experiment including airborne radar and surface altimetry augmented by satellite imagery, in addition to airborne gravity and aeromagnetic measurements within a carefully chosen West Antarctic corridor. This corridor covers the western portion of the Byrd Subglacial Basin and the easternmost portion of the Interior Ross Embayment. The experiment objectives will be achieved by imaging the tectonic fabric across the West Antarctic Rift system and characterizing the distribution of sedimentary basins, volcanic rocks and important ice dynamical boundaries within this corridor.