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

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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.