| Titre | Detrital-zircon provenance of a Torridonian fluvial-aeolian sandstone: the 1.2 Ga Meall Dearg Formation, Stoer Group (Scotland) |
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| Auteur | Lebeau, L E; Ielpi, A; Krabbendam, M; Davis, W J |
| Source | Precambrian Research vol. 346, 0301-9268, 2020 p. 1-19, https://doi.org/10.1016/j.precamres.2020.105822 |
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| Année | 2020 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20200105 |
| Éditeur | Elsevier B.V. |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1016/j.precamres.2020.105822 |
| Media | papier; en ligne; numérique |
| Formats | pdf; html |
| Région | Scotland; Northern Highlands |
| Lat/Long OENS | -7.7161 -4.5608 58.6483 56.7044 |
| Sujets | datation radiométrique; datation au uranium-plomb; datations au zircon; minéraux détritiques; zircon; origine; régions émettrices; transfert des sédiments; dépôts fluviaux; dépôts éoliens; géologie du
substratum rocheux; lithologie; grès; analyses par microsonde électronique; paléocourants; paléogéographie; cadre tectonique; décrochement horizontal; evolution du bassin; Archéen; Groupe de Stoer ; Complexe de Lewisian Gneiss ; géochronologie;
sédimentologie; Sciences et technologie; Nature et environnement; Précambrien; Protérozoïque |
| Illustrations | cartes de localisation; graphiques; diagrammes |
| Diffusé | 2020 06 10 |
| Résumé | (disponible en anglais seulement)
The Meall Dearg Formation is a 1.2 Ga fluvial-aeolian sandstone exposed in the northwestern Highlands of Scotland, and represents one of the least studied rock
units in the Torridonian succession, especially in terms of sedimentary provenance. Three hundred and nine detrital zircon grains were analysed from four samples of the Meall Dearg Formation using sensitive high-resolution ion microprobe, allowing
for its provenance to be resolved at the terrane scale. Ages range from c. 3,100 to c. 1,750 Ma, with dominant proportions between c. 2,900 and c. 2,650 Ma, and subordinate fractions of c. 2,500 Ma and c. 1,900 Ma. U-Pb protolith-zircon ages from
eight previous studies across the Lewisian Gneiss Complex were compiled and compared to detrital-age distributions of the Meall Dearg Formation. Strong similarities in age trends and palaeocurrent data corroborates the hypothesis of sedimentary
provenance from the Lewisian Gneiss Complex. Detritus was prevalently derived from the Rhiconich and Gruinard terranes, and subordinately from the Assynt, Gairloch (including the Loch Maree Group and Ard Gneiss), and Ialltaig terranes. Age
distributions from the fluvial and aeolian samples show near-matching distributions, indicating sediment transfer between adjacent depositional environments, and possibly derivation from similar source regions. The Meall Dearg Formation, part of the
Stoer Group, is postulated to record the overfilling stage of a rift basin near the eastern flank of the Columbia Supercontinent at c. 1.2 Ga. Critical comparisons can be drawn between the Stoer Group and Gardar Rift of southern Greenland, based on
their age, palaeogeography, and patterns of rift-basin development. |
| GEOSCAN ID | 326400 |
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