| Title | Devonian to Carboniferous continental scale carbonate turnover in Western Laurentia (North America): Upwelling or climate cooling? |
| |
| Author | Hedhli, M; Dewing, K ; Grasby, S; Beauchamp, B; Meyer, R |
| Source | Facies vol. 68, 15, 2022 p. 1-31, https://doi.org/10.1007/s10347-022-00653-4  Open Access |
| Image |  |
| Year | 2022 |
| Alt Series | Natural Resources Canada, Contribution Series 20210695 |
| Publisher | Springer |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Canada; British Columbia; Alberta; Saskatchewan; Manitoba; Ontario; Quebec; New Brunswick; Nova Scotia; Prince Edward Island; Newfoundland and Labrador; Northwest Territories; Yukon; Nunavut |
| NTS | 1; 2; 3; 10; 11; 12; 13; 14; 15; 16; 20; 21; 22; 23; 24; 25; 26; 27; 28; 29; 30; 31; 32; 33; 34; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44; 45; 46; 47; 48; 49; 52; 53; 54; 55; 56; 57; 58; 59; 62; 63; 64; 65;
66; 67; 68; 69; 72; 73; 74; 75; 76; 77; 78; 79; 82; 83; 84; 85; 86; 87; 88; 89; 92; 93; 94; 95; 96; 97; 98; 99; 102; 103; 104; 105; 106; 107; 114O; 114P; 115; 116; 117; 120; 340; 560 |
| Area | United States of America |
| Subjects | stratigraphy; carbonate; climate; Laurentia; Devonian; Carboniferous |
| Illustrations | location maps; stratigraphic columns; tables; photographs; cross-sections |
| Program | Energy Geoscience
Geothermal Energy |
| Released | 2022 07 25 |
| Abstract | The Devonian to Carboniferous (DC) transition coincided with a green-to-ice house climatic shift, anoxia, disappearance of lower latitude carbonate banks, and turnover from warm-to-cool water carbonate
factories. In western Laurentia, the switch to carbonate factories dominated by cool-water biota was contemporaneous with a tectonically driven palaeogeographic change. To investigate this depositional shift and infer the relative impact of climate
vs tectonics, a continentalscale sedimentological and geochemical study was conducted on twelve stratigraphic sections of DC strata from western Canada to southern Nevada (USA). The spatial-temporal distribution of microfacies records the turnover
from [i] a Famennian lime mud-rich, shallow warm-water carbonate ramp with low sedimentation rates, mesotrophic conditions and tabular geometry to [ii] Tournaisian to Visean lime mud-depleted and grainstone dominated cool-water carbonate ramp with
anomalous high sedimentation rates, oligotrophic conditions and a pronounced slope. Positive excursions of d18Ocarb (+ 2 per mil V-PDB) and ?13Ccarb (+ 4 per mil V-PDB) of Lower Mississippian carbonates likely correspond to the first cooling peak of
the Carboniferous-Permian icehouse climate, following carbon withdrawal during black shale deposition during the late Famennian and early Tournaisian. However, late Tournaisian return of photozoan elements and their persistence throughout the Visean
suggests that warmer surface water existed, revealing a decoupling of the lower latitude ocean and the atmosphere. Shoaling of the thermocline was likely a result of cold-water upwelling along an open coast, as the Antler orogen no longer provided an
oceanic obstruction to the west. This study shows that carbonate platforms are more susceptible to regional changes than global shifts. |
| Summary | (Plain Language Summary, not published)
Studying the depositional environment of Paleozoic rocks of western Canada allow us to understand the characteristics of these rocks as potential
reservoir for hot aquifer ( geothermal energy). |
| GEOSCAN ID | 329694 |
|
|