Lower Paleozoic stratigraphic architecture of the Cornwallis District and associated areas, Canadian high Arctic

这项拟议中的研究将由4名研究生和4名本科生承担，将破译加拿大北极岛屿下古生代（~ 5.4亿至~ 4.45亿年前）沉积演替的基本结构，这是一个3000公里长、2.5公里厚的古大陆边缘，从未在详细的、区域连贯的古环境-沉积学-年代学背景下进行过研究。使用标准的野外方法，如测量和描述层状岩石序列，并使用相对较新的稳定同位素对比方法和时间流逝的化石证据详细说明时间的流逝，我们将仔细梳理在这个序列中保存的地球表面环境的序列，在一个特别暴露良好且具有代表性的近岸到深海样带中，这样我们就能知道5亿年前加拿大北部三分之一的地区是什么样子的。这项工作将包括一个主题连贯的、环环相扣的马赛克研究，将首次产生一个完整的加拿大北部的演化年表，通过其被动边缘的早期发展，边缘大陆架和蒸发岩盆地的演化，以及与神秘的克林托克造山运动相关的事件，所有这些都与岩石演替中保存的不断变化的地球表面环境有关。该地区最引人注目的一个方面是，它暴露了一个罕见的穿过古大陆架边缘的样带，当时人们对生活在那里的生物的性质知之甚少；因此，这项研究也将揭示动物进化史早期重要但保存较差的古生态系统。此外，这些地层的组成和地层包裹，以及影响它们的构造，控制了与Cornwallis锌区（中央高纬度北极，包括过去生产的Polaris矿）相关的金属流体的后期迁移，并一直延伸到Ellesmere岛的北端。尽管Polaris矿成功地开采了20年，但富兰克林盆地中宿主岩石的详细沉积学和地层学从未得到详细研究，这些岩石具有巨大的区域范围和一致性以及巨大的经济潜力。

The proposed research, to be undertaken by four graduate students and four undergraduates, will decipher the fundamental architecture of Canada’s lower Paleozoic (~540 to ~445 million years ago) sedimentary succession in the Arctic islands, a 3000 km-long and 2.5 km-thick paleo-continental margin that has never been studied in a detailed, regionally coherent paleoenvironmental-sedimentological-chronological context. Using standard field methods such as measuring and describing layered rock successions, and detailing the passage of time using the comparatively new method of stable isotope correlation together with fossil evidence of the passage of time, we will carefully tease apart the succession of Earth-surface environments preserved in this succession, in one particularly well exposed and representative nearshore to deep-marine transect, so that we can tell the story of what the northern 1/3 of Canada was like half a billion years ago. The work will consist of a thematically coherent, interlocking mosaic of studies that will produce, for the first time, a holistic chronology of northern Canada’s evolution through early development of its passive margin, evolution of a rimmed continental shelf and evaporite basin, and events associated with the mysterious M’Clintock orogeny, all of which play into the changing Earth-surface environments preserved in the rock succession. One of the most compelling aspects of the area to be studied is that it exposes a rare transect through the paleo-continental shelf-edge at a time when little is known about the nature of organisms living there; this study will, therefore, also shed light on important but poorly preserved paleoecosystems dating from early in the evolutionary history of animals. Furthermore, the composition and stratigraphic packaging of these strata, together with the structures that affected them, controlled later migration of metalliferous fluids associated with base-metal mineralisation in the Cornwallis zinc district (central high Arctic; includes past-producing Polaris mine), and extending all the way to the northern tip of Ellesmere Island. In spite of the Polaris mine’s successful 20-year mine-life, the detailed sedimentology and stratigraphy of the host rocks in the Franklinian basin, which have immense regional extent and consistency, and significant economic potential, have never been addressed in detail.