Collaborative Research: Testing Three-Dimensional Kinematic Analysis of Mid-Crustal Ductile Shear Zones: Deformation within the Western Idaho Shear Zone

0001092造山带的Tikoff0003007McClelland构造模型依靠各种运动学指标来确定最大和最小应力方向、“伸展方向”和剪切感。一个基本的假设是，构造运输方向平行于矿物或伸展线理方向，然而，剪切带的三维数值模拟表明，这一假设并不总是有效的。这个项目将利用爱达荷州西部的剪切带来解决这个问题，该剪切带标志着在晚白垩世期间异地地体向西向北美板块的吸积。运动学和地质学数据已经导致了几个不同的模型来描述这种吸积。这项研究是一项综合的构造、微构造和U/Pb年代学项目，旨在确定爱达荷州西部晚白垩世剪切带的运动学历史，将使用三维技术来检验构造搬运与线理平行假设的有效性。结果应该有助于澄清这种缝合的运动学，并评估在其他地方解释许多造山带时使用的重要运动学假设之一。

0001092 Tikoff0003007 McClellandTectonic models for orogenic belts rely on various kinematic indicators to determine such things as maximum and minimum stress directions, "stretching directions" and sense of shear. One fundamental assumption has been that tectonic transport directions parallel mineral or extension lineation directions, however three-dimensional numeric modeling of shear zones indicates that this is not always a valid assumption. This project will address this issue using the western Idaho shear zone that marks the accretion of allochthonous terranes to the west to the north American plate during the Late Cretaceous. The kinematic and geologic data have resulted in several, disparate models for this accretion. This study is an integrated structural, microstructural and U/Pb geochronologic project designed to determine the kinematic history of the late Cretaceous western Idaho shear zone that will employ three-dimensional techniques to test the validity of the assumption that tectonic transport is parallel to lineation. Results should help clarify the kinematics of this suture and evaluate one of the important kinematic assumptions used in interpretations of many orogens elsewhere.