COLLABORATIVE RESEARCH: Tectonic Reconstructions of Southwestern North America

美国西南部的前寒武纪和下古生代大陆地壳由于各种板块的相互作用而发生了广泛的古生代、中生代和新生代变形。许多大型运输断层被认为与这些较年轻的事件有关，但由于缺乏对较老岩石的原始空间分布的了解，证明或量化它们的努力受到阻碍。这个项目将利用一种新的方法来建立现在分离的地形的古接近性。最近的研究发现了一种具有非常独特的Nd同位素特征的1.1级花岗岩，其侵蚀产物可以在可疑地体沉积的沉积物中识别出来。通过寻找锆石碎屑中的l1和候选沉积物中的Nd峰值，可以估计与这一独特来源的接近程度。来自几个关键地形的此类数据将有助于建立它们的原始空间关系，从而确定后续的翻译。研究结果有望帮助解决美国西南部克拉通重建过程中的几个区域问题。

9725829 Farmer The precambrian and lower paleozoic continental crust of southwestern United States has been involved in extensive paleozoic, Mesozoic and Cenozoic deformation caused by a variety of plate interactions. Many large-transport faults have been proposed for these younger events, but attempts to prove or quantify them is hampered by the lack of knowledge of the original spatial distribution of the older rocks. This project will utilize a new approach to establish paleo-proximity of now separated terranes. Recent studies have identified a 1.1 by granite with a very unique Nd isotopic signature, erosion products of which can be identified in sediments deposited in the suspect terranes. Proximity to this unique source can be estimated by looking for l.1 by zircon detritus and the Nd spike in candidate sediments. Such data from several key terranes will help establish their original spatial relationship thus allowing the subsequent translations to be determined. Results are expected to assist in resolving several regional problems in the reconstruction of the southwest US craton.