40Ar/39Ar Dating of Metamorphism and Crustral Reactivation in the Eastern Sierras Pampeanas Arc, Argentina

9903166埃里森在阿根廷的前心山脉中发现的劳伦提斯类岩石导致了一系列可能的古生代地体平移和增生的情景。然而，地质关系和变形的年龄控制还不足以在几个现有模型之间进行测试。该项目将尝试确定高级别寒武纪弧中异常低变质级别剪切带的日期和特征，该弧随后与奥陶纪低级别弧并置，并被泥盆纪侵入。结果应允许这些剪切带与构造事件在翻译和增生的这些火山岩，从而更清晰地了解北美和南美之间的古生代构造作用。

9903166SimpsonThe recognition of laurentian-affinity rocks in the precordillera terrane of Argentina has led to a suite of possible scenarios of Terrane translation and accretion during paleozoic time. However, geologic relationships and age control of deformation are not sufficiently developed to be able to test between several current models. This project will attempt to date and characterize anomalously low metamorphic grade shear zones in a high grade Cambrian arc that was subsequently juxtaposed against an Ordovician low-grade arc to the west and intruded by Devonian plutons. Results should allow these shear zones to be correlated with tectonic episodes during the translation and accretion of these terranes, leading to a clearer picture of Paleozoic tectonism between North and South America.