COLLABORATIVE RESEARCH: 40 Ar/39 Ar and Structural Investi-gation and Constraints for the Tectonothermal Evolution of the Avalon Composite Terrane, SW New Brunswick

阿巴拉契亚山脉北方的阿瓦隆复合山脉 造山带代表了一组构造地层学的集合体， 在前寒武纪晚期合并， 早-中古生代进入北美， 随后分散在相对于每个 其他. 内组成地体元素的识别 复合材料的使用一直存在争议， 构造演化是不确定的， 并合、增生和扩散的限制很差。 该项目将通过一项全面的 一个新构造带构造和40 Ar/39 Ar年代学研究 阿瓦隆复合材料的代表性部分， 新玩法西南部，最近的研究表明， 可能存在重要晚期前寒武纪界线。 结果 40 Ar/39 Ar同位素普查结果表明， 在拟议的研究领域可以作出重大贡献。 该项目结合了详细的构造测绘运动学 40 Ar/39 Ar分析和岩石学研究 矿物年代测定旨在解决该地区的构造 进化 这项研究将大大提高对 记录的构造活动的性质、时间和运动学 在阿瓦隆复合材料中， 有利于后期组分的识别和对比 前寒武纪化石。

The Avalon composite terrane of the northern Appalachian orogen represent a college of tectonostratigraphic terranes that were amalgamated in the late Precambrian, accreted as a composite terrane to North America during the early-middle Paleozoic, and were subsequently dispersed variable distances relative to each other. Identification of the constituent terrane elements within the composite terrane has been controversial, their tectonothermal evolution is uncertain, and the nature and timing of amalgamation, accretion and dispersal are poorly constrained. This project will address these issue through a comprehensive structural and 40Ar/39Ar geochronological study of a representative portion of the Avalon composite terrane in southwestern New Brunswick where recent studies have shown an important late Precambrain terrane boundary may exist. Results of a reconnaissance 40Ar//39Ar isotopic survey indicate that a significant contribution can be made in the proposed study area. The project couples detailed structural mapping kinematic analysis and petrological studies with a program of 40Ar/39Ar mineral dating designed to resolve the region's tectonothermal evolution. The study will substantially improve knowledge of the nature, timing and kinematics of tectonothermal events recorded in the Avalon composite terrane and, thereby, will greatly facilitate the identification and correlation of constituent late Precambrian terranes.