Detrital Zircon Constraints on the Displacement History of Terranes in Western Nevada and Northern California

碎屑锆石对内华达州西部和加利福尼亚州北部地体位移历史的约束

• 批准号: 9416933
• 负责人: George Gehrels
• 金额: $ 13.59万
• 依托单位: University of Arizona
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-11-15 至 1997-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9416933&HistoricalAwards=false
• 关键词: Detrital; Zircon; Constraints; Displacement; History

9416933 Gehrels One of the fundamental questions in Cordilleran tectonics is the degree of orogen-parallel transport of outboard terranes before final docking and amalgmations to North America. Paleomagnetic data has commonly been used to determine latitude shifts of allochthouous terranes, but the method has many possible sources of error. As a result, geologic data is frequently at adds with paleomagnetic interpretations. This project intends to employ an entirety different technique to detect and quantify orogen-parallel terrane translation. Prior work has assembled a database of the distribution of zircons in source rocks along the western north american craton. This project will examine suites of detrital zircons from outboard terranes and match their age distributions to the North American craton database to estimate the degree of allochthoniety. Successful results will provide an independent test for possible northward translation of several exotic terranes in western Nevada and northern California, thereby helping to resolve the discrepancy between paleomagnetic results and geology analysis. ***

小行星9416933 科迪勒拉构造学中的一个基本问题是，在最后对接和汞齐作用到北美之前，外大陆的造山带平行运输的程度。 古地磁资料常被用来确定外来岩的纬度变化，但这种方法有许多可能的误差来源。 因此，地质资料常常与古地磁解释相矛盾. 该项目打算采用一种完全不同的技术来检测和量化造山带平行的平移。 先前的工作已经建立了一个关于沿着北美克拉通西部源岩中锆石分布的数据库。 本计画将检视来自外大陆的碎屑锆石，并将其年龄分布与北美克拉通资料库比对，以估计其异源程度。 成功的结果将为内华达州西部和加州北方的几个外来的地幔可能向北平移提供一个独立的测试，从而有助于解决古地磁结果和地质分析之间的差异。 ***