Building mountain belts - the Appalachian model

地球上的每条山脉带都是独一无二的，但类似的过程很可能发生在所有山脉的形成过程中。其中一个过程是外来碎片或地体的堆积。我的研究计划专注于在阿巴拉契亚山脉地带北部识别这些碎片，解释它们来自地球上的哪里，并了解它们如何、何时以及为什么与祖先北美相连。我的工作模型识别阿巴拉契亚造山带北部和欧洲相关带中的碎片，这些碎片来自三个独立的微大陆，即梅古马、阿瓦洛尼亚和甘德里亚。我们在理解这些片段方面取得了很大进展，但问题仍然存在。该提案侧重于两个具体的问题领域：(1)布雷顿角中部的甘德里亚部分地区和(2)新斯科舍省大陆北部的阿瓦洛尼亚部分地区。我将以野外测绘为基础，更好地确定岩石单位，然后对仔细收集的代表性样本进行矿物、结构和化学研究、年代测定和同位素分析，以破译这些地区岩石的年龄和成因。 这项工作对地球科学家来说很重要，他们工作的地区可能是山脉带的组成部分和/或盘古大陆解体后以前的组成部分可能分散到的地区。更广泛地说，这项工作对于那些试图了解阿巴拉契亚造山带北部造山的基本过程的人来说很重要。我与来自加拿大、美国、英国、西班牙、法国和德国的地球科学家的广泛合作证明了我的工作的相关性。我的研究涉及本科生和研究生，因此，对学生的资助是我预算中最大的部分。我的学生学习如何在野外解释岩石，获取和使用分析数据，进行公开演讲，以及撰写科学论文。我们预计，新的结果与以前工作和其他地区的结果相结合，将导致阿巴拉契亚北部山区建设的最终和内部一致的模式，并广泛适用于其他山区。这样的了解应该会导致更多和更成功的矿产勘探计划，特别是如果像我们预期的那样，与纽芬兰中部和新不伦瑞克省矿产丰富地区的岩石单位有关的岩石单位能够被证明存在于布雷顿角。

Each mountain belt on Earth is unique, but similar processes likely took place in the formation of all. One of those processes is the accretion of exotic fragments or terranes. My research program focuses on identifying such fragments in the northern part of the Appalachian mountain belt, interpreting from where on the Earth they were derived, and understanding how, when, and why they were attached to ancestral North America. My working model recognizes fragments in the northern Appalachian orogen and correlative belts in Europe derived from three separate microcontinents named Meguma, Avalonia, and Ganderia. We have made much progress toward understanding these fragments, but problems remain. This proposal focuses on two specific problem areas: (1) the part of Ganderia in central Cape Breton Island and (2) the part of Avalonia in northern mainland Nova Scotia. I will use field mapping as a basis to better define rock units, followed by mineral, textural, and chemical studies, dating, and isotopic analyses of carefully collected representative samples to decipher the ages and origins of the rocks in these areas. This work is important to geoscientists who work in areas from which components of the mountain belt may have been derived and/or to which former components may have been dispersed after the break-up of Pangaea. More broadly, the work is important to those who are trying to understand the fundamental processes of mountain building as exemplified in the northern Appalachian orogen. The relevance of my work is demonstrated by the extent of my collaborations with geoscientists from not only Canada but also the USA, UK, Spain, France, and Germany. My research involves students at both the undergraduate and graduate (MSc) levels and hence funding for students is the largest component of my budget. My students learn how to interpret rocks in the field, acquire and use analytical data, make public presentations, and write scientific papers. We anticipate that the new results, integrated with those from previous work and from other areas, will lead to a definitive and internally consistent model for northern Appalachian mountain building, with broad applicability to other mountain belts. Such understanding should lead to increased and more successful mineral exploration programs, especially if, as we anticipate, rock units related to those in mineral-rich areas in central Newfoundland and New Brunswick can be demonstrated to be present in Cape Breton Island.