Collaborative International Research: Investigation of Structures, Structural Fabrics and Metamorphic Associations in Northern Victoria Land

9702161 Siddoway摘要该奖项允许一名美国调查员加入意大利南极计划在南极洲维多利亚州北部的地质野外小组。该野外计划的总体目标是获得与维多利亚北部地区早古生代岩浆活动历史有关的详细的构造、岩石学、同位素和地质年代学信息，并将这些信息与罗斯造山作用期间的板块会聚联系起来。该小组将检验这一假设，即NVL中的高温-低压变质作用发生在基本上与弧形有关的深成岩的区域接触变质光环内，处于与会聚有关的构造制度内。PI的详细构造研究有望有助于描述深成岩体侵位的动态环境，并将围岩中的结构组构与围岩中变质重结晶的压力-温度条件的变化联系起来。这项工作将被用来验证深成岩浆作用期间岩浆弧极性，并建立与南方早古生代深成岩体的关系。这项工作的结果将被用于推断NVL的南极洲早古生代活动边缘的形状，以便与横贯北极山脉其他地区开发的模型进行比较。在这项工作中形成的解释将与对冈瓦那原太平洋边缘其他部分的构造和构造解释结合起来。研究中使用的方法将包括构造制图、构造和变质岩石学以及流体包裹体分析。现场计划以深度冻结范围为中心，并有可能检查兰特曼山脉附近的地点。该奖项支持的具体贡献将是研究和解释变形、岩浆脉冲和高温-低压变质再结晶之间的关系。

9702161 Siddoway Abstract This award allows a US investigator to join an Italian Antarctic Program geological field team in northern Victoria Land, Antarctica. The overall goal of the field program is to obtain detailed structural, petrographic, isotopic, and geochronological information that bears on the history of early Paleozoic magmatism in northern Victoria Land (NVL), and to relate this information to plate convergence during the Ross Orogeny. The group will test the hypothesis that high temperature-low pressure metamorphism in NVL occurred within the regional contact metamorphic aureole of fundamentally arc-related plutons, within a structural regime related to convergence. Detailed structural studies by the PI are expected to help characterize the dynamic setting in which the plutons were emplaced and correlate structural fabrics in host rock with changes in pressure- temperature conditions of metamorphic recrystallization in host rocks. The work will be used to verify the polarity of the magmatic arc during plutonism and establish the relationships with early Paleozoic plutons to the south. The results of this work will be used to infer the configuration of AntarcticaOs early Paleozoic active margin in NVL, for comparison with models developed in other parts of the Transantarctic Mountains. Interpretations developed in the course of this work will be integrated with tectonic and structural interpretations for other parts of the proto-Pacific margin of Gondwana. Methods used in the study will include structural mapping, structural and metamorphic petrology, and fluid inclusion analysis. The field program in \centered on the Deep Freeze Range, with an additional possibility of examining sites in the vicinity of the Lanterman Range. The specific contribution supported by this award will be study and interpretation of the relations between deformation, magmatic pulses, and high temperature-low pressure metamorphic recrystallization.