COLLABORATIVE RESEARCH: Alternating Contraction and Extension During the Late Mesozoic to Early Cenozoic, Northwestern Utah

9317044 Hoisch理论和物理模型以及野外研究表明，收缩和伸展交替的复杂构造历史可以在收缩造山带内部发展，基本上在造山带的生长过程中调节地壳厚度。该项目将试图通过在犹他州西北部的拉夫河和格罗斯克里克山脉的塞维尔造山带腹地的地壳中部暴露来测试这些模型。这项工作将涉及构造填图、变质温压测量、P-T-t路径模拟和几种地质年代学技术。这项研究将讨论该地区形变历史的几个组成部分，并检验几个现有的中生代区域收缩和造山后伸展期间地壳中期演化的模型。它还将有助于连接腹地和前陆冲断带之间可能的同世变形。***

9317044 Hoisch Theoretical and physical models as well as field studies suggest that complex structural histories involving alternating contraction and extension can develop within the interior of contractional orogenic belts, essentially moderating crustal thickness during the growth of the orogenic belt. This project will attempt to test these models by use of mid-crustal exposure of the hinterland of Sevier Orogen in the Raft River and Grouse Creek Mountains of northwestern Utah. The work will involve structural mapping, Metamorphic thermobarometry, P-T-t path modeling, and several geochronologic techniques. This study will address several components of the deformation history of the area and test several existing models for middle crustal evolution during Mesozoic regional contraction and post-orogenic extension. It will also help link the possible coeval deformations between the hinterland and the foreland thrust belt. ***