COLLABORATIVE RESEARCH: U-Pb Geochronolgy of Precambrian Gneisses in Southern California: Constraints on Proterozoic Plate Tectonics of Southwestern North America

合作研究：南加州前寒武纪片麻岩的 U-Pb 年代学：对北美西南部元古界板块构造的约束

• 批准号: 9614511
• 负责人: Drew Coleman
• 金额: $ 5.23万
• 依托单位: Trustees of Boston University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-01-01 至 1999-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9614511&HistoricalAwards=false
• 关键词: COLLABORATIVE; RESEARCH; Pb; Geochronolgy; Precambrian

9614511 Coleman The plate configurations during Precambrian time are difficult to reconstruct, but are of considerable interest, both from a global perspective (style of tectonics including assembly of supercontinents) and more local (influence of precambrian geometry on younger events). This project will examine early proterozoic gneisses in southern California that contain evidence of a deformation event, possibly associated with an arc and a western Archean (?) craton. The study will support mapping and structural analysis of this hypothesized arc accretion event in the western mojave province, supported by U-Pb geochronology to constrain the timing of orogeny. Insights into the origin of the Mojave province from this study will provide important constraints on geochemical models for Precambrian growth of the North American craton, subsequent deformation and plate tectonic models for accretion of the Late Proterozoic supercontinent.

前寒武纪时期的板块构造很难重建，但无论是从全球的角度（构造风格包括超大陆的组合）还是从更局部的角度（前寒武纪几何对年轻事件的影响）来看，都具有相当大的意义。该项目将研究南加州的早元古代片麻岩，这些片麻岩含有变形事件的证据，可能与弧和西部太古宙克拉通有关。该研究将支持莫哈韦省西部这一假设的弧增生事件的制图和构造分析，并支持U-Pb年代学来约束造山运动的时间。该研究将为北美克拉通前寒武纪生长的地球化学模型、晚元古代超大陆增生的后续变形和板块构造模型提供重要的约束。