| Title | Geological history and supercontinent cycles of the Arctic |
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| Author | Harrison, J C; St-Onge, M R |
| Source | Geological Society of America Bulletin 2022 p. 1-28, https://doi.org/10.1130/B36398.1 |
| Image |  |
| Year | 2022 |
| Alt Series | Natural Resources Canada, Contribution Series 20190491 |
| Publisher | The Geological Society of America |
| Document | serial |
| Lang. | English |
| Media | on-line; digital |
| File format | pdf |
| Province | Northwest Territories; Nunavut; Yukon |
| NTS | 15; 25; 35; 45; 55; 65; 75; 85; 95; 105; 115; 16; 26; 36; 46; 56; 66; 76; 86; 96; 106; 116; 27; 37; 47; 57; 67; 77; 87; 97; 107; 117; 28; 38; 48; 58; 68; 78; 88; 98; 19; 29; 39; 49; 59; 69; 79; 89; 99; 120;
340; 560 |
| Area | Russian Federation; Greenland |
| Lat/Long WENS | -180.0000 180.0000 90.0000 60.0000 |
| Subjects | general geology; arctic geology; geological history; craton; Laurentia; Baltica; Precambrian Shield; Rodinia |
| Illustrations | location maps; schematic cross-sections; photographs |
| Program | Open Geoscience |
| Released | 2022 05 04 |
| Abstract | The geological history of the Arctic is constrained within the framework of the assembly and breakup of three supercontinents. The first of these was preceded by the crystallization of the oldest dated
rocks on Earth and consolidation of the Arctic region's Archean cratons between 2.82 and 2.54 Ga. Following the emplacement of regional mafic dike swarms between 2.51 and 2.03 Ga, the cratons were amalgamated into the Nuna (Columbia) supercontinent
between 2.0 and 1.6 Ga, and the distribution of low-thermal-gradient eclogite (indicative of continental subduction) and ophiolite (indicative of obduction of oceanic crust onto a continental margin) suggests that diagnostic plate-tectonic processes
were well in place by the early Paleoproterozoic. Basin formation, flood basalts, and dike swarms are features of the partial(?) breakup of Nuna (Columbia) by 1.5-1.27 Ga. The extent to which specific dike swarms led to continental breakup and a
rift-to-drift transition remains unclear. Assembly of the second supercontinent (Rodinia, 1.4- 0.9 Ga) is recorded by a network of Grenvillian and Sveconorwegian collisional orogenic belts. Prominent features of Rodinia breakup (780-615 Ma) in the
Arctic are extensive dike swarms and regional-scale glacial-periglacial deposits associated with the Sturtian (717-661 Ma) and Marinoan (ca. 645 ± 6 to ca. 635 Ma) snowball Earth glaciations. Assembly of the third supercontinent, Pangea, between 600
Ma and ca. 250 Ma, was accomplished through stitching of four orogens in the Arctic (Timan-Varanger, Caledonian, Ellesmerian, and Urals-Taymyr). Pangea breakup (rifting since 250 Ma and oceanic spreading since the Cretaceous) led to the emplacement
of Cretaceous and Paleogene flood basalts, new oceanic crust in the Labrador Sea, North Atlantic Ocean, and Arctic Ocean, and orogens characterized by relatively small but far-traveled accreted terranes with provenance in Laurentia, Baltica, and
Siberia. Paleogeographic similarities and geological correlations among Laurentia, Baltica, Siberia, and the North China craton suggest that Rodinia formed following incomplete breakup of Nuna (Columbia) and/or by introversion, whereas unique
paleogeographic traits for Pangea within the Arctic region point to supercontinent formation by extroversion. |
| Summary | (Plain Language Summary, not published)
The history of the Arctic is highlighted by the assembly and break-up of three supercontinents. The early Archean cratons were amalgamated into the Nuna
supercontinent at 2.0 to 1.75 Ga. Basin formation, flood basalts and dyke swarm emplacement are features of Nuna break-up from 1.5 to 1.27 Ga. Rodinia, the second supercontinent, was assembled by the Grenville orogen and its equivalents in the
Arctic. A prominent feature of Rodinia break-up (780-615 Ma) are three dyke swarms and the diamictite deposits of the Cryogenian-Ediacaran glaciations. Assembly of the third supercontinent, Pangaea between 600 and 250 Ma, was accomplished through
four stitching orogens (Timan-Varanger, Caledonian, Ellesmerian, and Urals-Taymyr). The subsequent Pangaea break-up (since 250 Ma) led to accumulation of Cretaceous and Paleogene flood basalts (in Greenland and the central Arctic), new ocean crust in
Labrador Sea, North Atlantic and Arctic, and development of the youngest of the Arctic orogens in Northwest Territories, Yukon, Alaska, and the Russian Far East. |
| GEOSCAN ID | 321632 |
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