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

加拿大高北极地区康沃利斯地区及相关地区的下古生代地层结构

• 批准号: RGPIN-2016-06596
• 负责人: Turner, Elizabeth
• 金额: $ 3.06万
• 依托单位: Laurentian University of Sudbury
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=688496
• 关键词: Lower; Paleozoic; stratigraphic; architecture; Cornwallis

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.******

拟议的研究将由四名研究生和四名本科生进行，将破译加拿大下古生代（约 540 至约 4.45 亿年前）沉积序列的基本结构，该沉积序列长 3000 公里，面积 2.5 公里。厚厚的古大陆边缘从未在详细的、区域一致的古环境-沉积学-年代学背景下进行过研究。使用标准现场方法，例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相关方法以及时间流逝的化石证据来详细说明时间的流逝，我们将仔细梳理地球表面环境的序列在这一序列中，在一个特别暴露且具有代表性的近岸到深海横断面中，我们可以讲述加拿大北部 1/3 地区 5 亿年前的情况。这项工作将包括一系列主题连贯、环环相扣的研究，首次通过被动边缘的早期发展、边缘大陆架和蒸发盆地的演化以及相关事件，形成加拿大北部演化的整体年表。神秘的麦克林托克造山运动，所有这些都影响了岩石序列中保存的不断变化的地球表面环境。该研究区域最引人注目的方面之一是，它暴露了一条穿过古大陆架边缘的罕见横断面，而当时人们对生活在那里的生物体的性质知之甚少；因此，这项研究还将揭示动物进化史早期重要但保存不良的古生态系统。此外，这些地层的成分和地层堆积，以及影响它们的结构，控制了与康沃利斯锌区（中高北极；包括过去生产的北极星矿）的贱金属矿化相关的金属流体的后期迁移，以及一直延伸到埃尔斯米尔岛的北端。尽管北极星矿拥有 20 年的成功采矿寿命，但富兰克林盆地围岩的详细沉积学和地层学从未得到详细研究，这些区域具有巨大的区域范围和一致性，以及巨大的经济潜力。** ****