Geology and Geochronology of the Byrd Glacier Discontinuity, Antarctica-A Pilot Study

9909463树桩该奖项支持一项试点研究，以调查位于伯德冰川下方的跨南极山脉罗斯造山带的主要地质不连续性。 调查将集中在伯德冰川以南的东部地区，开始将在2000-2001年进行为期六周的实地调查，重点是两个明显不同的岩石群：1）伯德群（早寒武世沙克尔顿石灰岩和年轻的道格拉斯砾岩）将在结构上绘制地图，以了解其运动学演化。 2)斜长角闪岩级变质岩（Selbourne Marble），在Mt.麦迪逊，将被详细绘制和收集，以表征其结构和变质历史，以及其地质年代学。直升机侦察将沿着沙克尔顿石灰岩中伯德冰川的西南侧和不列颠尼亚山脉中伯德冰川的北侧火成岩和高级变质岩（霍尼组）进行。 亚利桑那州立大学将减少结构数据。 塞尔伯恩大理石的变质研究将在锡耶纳大学进行。 将在俄亥俄州州立大学（40 Ar/39 Ar，Sm-Nd）和堪萨斯大学（U-Pb）进行同位素研究，以确定塞尔伯恩大理石的热年代学，并限制道格拉斯砾岩的来源年龄。

9909463StumpThe 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.