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: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=751203
• 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.

拟议中的研究，将由四名研究生和四名本科生进行，将破译加拿大的下古生代（~540 ~ 445万年前）在北极岛屿，3000公里长，2.5公里厚的古大陆边缘，从来没有被研究过的详细，区域连贯的古环境沉积年代背景下的沉积序列的基本架构。使用标准的野外方法，如测量和描述层状岩石的演替，并使用相对较新的稳定同位素相关方法以及时间推移的化石证据来详细说明时间的推移，我们将仔细梳理保存在这一演替中的地球表面环境的演替，在一个特别暴露和具有代表性的近岸到深海样带中，这样我们就可以讲述加拿大北方1/3地区在5亿年前的情况。这项工作将包括一个主题连贯的，环环相扣的马赛克研究，将产生，第一次，加拿大北方的演变，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变，以及与神秘的麦克林托克orthodium相关的事件，所有这些都发挥到不断变化的地球表面环境中保存的岩石继承的整体年表。待研究地区最引人注目的方面之一是，它暴露了一个罕见的穿越古大陆架边缘的断面，当时人们对生活在那里的生物的性质知之甚少;因此，这项研究也将揭示重要但保存不良的古生态系统，这些生态系统可以追溯到动物进化史的早期。此外，这些地层的组成和地层包装，以及影响它们的结构，控制了与康沃利斯锌区（北极中部高海拔地区;包括过去生产的北极星矿）的贱金属矿化有关的含金属流体的后期迁移，并一直延伸到埃尔斯米尔岛的北方尖端。尽管Polaris矿成功地开采了20年，但富兰克林盆地中寄主岩石的详细沉积学和地层学从未得到详细讨论，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。