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

该奖项支持一项初步研究，以调查位于伯德冰川之下的横贯北极山脉的罗斯造山带的一个主要地质不连续点。调查将集中在伯德冰川以南的东部地区，2000-2001年将进行为期六周的野外考察，重点关注两个截然不同的岩组：1)将绘制伯德群(早寒武世沙克尔顿石灰岩和年轻的道格拉斯砾岩)的结构图，以了解其运动学演化。2)出露于山体周围的角闪岩级变质岩(塞尔本大理岩)。麦迪逊，将被详细绘制和收集，以表征其构造和变质历史，以及其地质年代学。直升机侦察将沿着沙克尔顿石灰岩的伯德冰川西南侧和不列颠山脉火成岩和高级变质岩(霍尼组)的伯德冰川北侧进行。亚利桑那州立大学将减少结构性数据。对塞尔本大理石的变质研究将在锡耶纳大学进行。俄亥俄州立大学(40Ar/39Ar，Sm-Nd)和堪萨斯大学(U-Pb)将进行同位素研究，以确定塞尔本大理石的热年代学，并限制道格拉斯集团的起源年龄。

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.