The award supports a pilot study to investigate a major geological discontinuity in the Ross orogen of the Transantarctic Mountains, located beneath Byrd Glacier. Concentrating on the eastern portion of the area immediately to the south of Byrd Glacier, the investigation will begin with a six-week field season in 2000-2001 focusing on two distinctly different rock groups: 1) the Byrd Group (Early Cambrian Shackleton Limestone and younger Douglas Conglomerate) will be mapped structurally toward an understanding of its kinematic evolution. 2) Amphibolite-grade metamorphic rocks (Selbourne Marble), which crop out around Mt. Madison, will be mapped in detail and collected to characterize its structural and metamorphic history, as well as its geochronology. Helicopter reconnaissance will be conducted along the southwestern side of Byrd Glacier in Shackleton Limestone, and on the north side of Byrd Glacier in the Britannia Range in igneous and high-grade metamorphic rocks (Horney Formation). Structural data will be reduced at Arizona State University. Metamorphic studies of the Selbourne Marble will be conducted at the University of Siena. Isotopic studies will be conducted at The Ohio State University (40Ar/39Ar, Sm-Nd), and at the University of Kansas (U-Pb) toward determining the thermochronology of the Selbourne Marble and constraining the provenance age of the Douglas Conglomerate.
