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

9416933盖瑞尔科迪勒构造的基本问题之一是造山带在最终对接和合并到北美之前，外侧地体的平行运移程度。古地磁数据通常被用来确定异地地体的纬度位移，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结合。该项目打算使用一种完全不同的技术来检测和量化造山带-平行地体的转换。先前的工作已经建立了北美克拉通西部源岩中锆石分布的数据库。该项目将检查来自外侧地体的碎屑锆石套件，并将它们的年龄分布与北美克拉通数据库进行匹配，以估计异形体的程度。成功的结果将为内华达州西部和加利福尼亚州北部几个外来地体可能向北移动提供独立的测试，从而有助于解决古地磁结果与地质分析之间的差异。***

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. ***