A Paleozoic accretion history ... : igneous and detrital zircon signatures of the Kulutingwak and Danish River formations in the Yelverton Inlet-Phillips Inlet region, Ellesmere Island, Nunavut, Canada ...
Juxtaposition of the composite Pearya terrane with the northern Laurentian margin at Ellesmere Island, Nunavut, Canada is an understudied tectonic event that has significant ramifications for the tectonic histories of other crustal fragments in the circum-Arctic region during the Paleozoic. Two end...
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Format: | Text |
Language: | English |
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University of Iowa
2021
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Online Access: | https://dx.doi.org/10.25820/etd.006995 https://iro.uiowa.edu/esploro/outputs/graduate/9984454542402771 |
Summary: | Juxtaposition of the composite Pearya terrane with the northern Laurentian margin at Ellesmere Island, Nunavut, Canada is an understudied tectonic event that has significant ramifications for the tectonic histories of other crustal fragments in the circum-Arctic region during the Paleozoic. Two end member models for accretion currently exist: 1) translation and emplacement along a sinistral margin-parallel strike-slip system, or 2) orthogonal collision with the Laurentian margin. Current hypotheses regarding this accretionary event rely upon interpretation of the Kulutingwak formation, an Ordovician sedimentary package often identified as a subduction-related sequence, and the Danish River formation, a laterally continuous unit often cited as a post-accretionary overlap assemblage. ... : Geologic relationships present in the Yelverton Inlet-Phillips Inlet region offer a unique opportunity to understand this accretion event, where the Ordovician Kulutingwak formation separates the crystalline basement of the Pearya terrane from the Silurian Danish River formation. Seventeen igneous and detrital zircon samples were collected from this area for U-Pb and Lu-Hf analysis in order to better characterize the Paleozoic sedimentary packages which underpin current tectonic models. Detrital zircon age distributions from the Kulutingwak formation demonstrate a transition from signatures indicative of the Laurentian margin to those diagnostic of the Pearya terrane in the Late Ordovician. Detrital zircon signatures in the Danish River formation record a dynamic tectonic setting in the Silurian where distinct facies belts with variable provenance signals are preserved. Both units are disturbed by late translation along major northeast-southwest striking structures and included in structural assemblages, ... |
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