| Titre | Evolution of late Palaeozoic shearing in the Cobequid Highlands: constraints on the fragmentation of the Appalachian orogen in Nova Scotia along intra-continental shear zones during the formation of
Pangea |
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| Auteur | Piper, D J W ;
Pe-Piper, G |
| Source | Pannotia to Pangaea: Neoproterozoic and Paleozoic orogenic cycles in the circum-Atlantic region; par Murphy, J B (éd.); Strachan, R A (éd.); Quesada, C (éd.); Geological Society, Special Publication vol.
503, 2020 p. 1-20, https://doi.org/10.1144/SP503-2019-239 |
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| Année | 2020 |
| Séries alt. | Ressources naturelles Canada, Contribution externe 20190545 |
| Éditeur | Geological Society of London |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1144/SP503-2019-239 |
| Media | papier; en ligne; numérique |
| Formats | pdf |
| Province | Nouvelle-Écosse |
| SNRC | 11D/05; 11D/06; 11D/11; 11D/12; 21A/07; 21A/08; 21A/09; 21A/10 |
| Région | Cobequid Highlands |
| Lat/Long OENS | -65.0000 -63.0000 45.5833 45.3333 |
| Sujets | évolution tectonique; orogénies; cisaillement; déformation; formation de failles; déplacement; antecedents thermiques; magmatisme; intrusions; filons rocheux; plutons; volcanisme; géologie du substratum
rocheux; caractéristiques structurales; zones de cisaillement; zones de failles; failles; failles, décrochement; fosses d'effondrement; lithologie; roches ignées; roches intrusives; gabbros; granites; roches sédimentaires; biostratigraphie; origine;
etudes isotopiques; néodyme; datations radiométriques; Orogène Appalachien; Orogenèse Acadienne; Orogenèse Alleghanienne; Zone de cisaillement de Cobequid ; Laurentie; Faille de Cobequid-Chedabucto ; Groupe d'Horton ; Faille de Kirkhill ; Faille de
Rockland Brook ; Faille de Cobequid ; Groupe de Fountain Lake ; tectonique; paléontologie; stratigraphie; géochimie; géochronologie; Sciences et technologie; Nature et environnement; Phanérozoïque; Paléozoïque; Permien; Carbonifère;
Dévonien |
| Illustrations | cartes géolscientiques généralisées; cartes géochronologiques; coupes stratigraphiques; coupes schématiques transversales; photographies; photomicrographies |
| Programme | Division de la CGC atlantique |
| Diffusé | 2020 05 20 |
| Résumé | (disponible en anglais seulement)
The Cobequid Highlands of northern Nova Scotia lie at the intersection of two major dextral intra-continental shear zones developed during closure of the Rheic
Ocean and formation of Pangea. The Cobequid Shear Zone was an ENE-WSW transfer zone in a NE-SW-trending orogen-parallel shear system in the late Devonian-early Carboniferous (Neo-Acadian phase), in which syn-tectonic granite-gabbro plutons and
volcanic strata 4 km thick were progressively deformed along multiple faults. In late Carboniferous to Permian, Alleghanian collision of Africa with Laurentia formed the E-W trending Minas Fault Zone, reactivating parts of the Cobequid Shear Zone.
This deformation was mostly taken up on the master Cobequid-Chedabucto Fault. Deformation chronology is well constrained by biostratigraphy of syn-tectonic sediments and by radiometrically dated igneous rocks and minerals in faults and veins. Early
strike-slip faults were lubricated by magmatic heating, leading to dyke to pluton construction along multiple faults. During cooling, rooted gabbro was more resistant than ductile granite, thereby deflecting solid-state deformation. Neo-Acadian
strike-slip displacement across the shear zone is estimated as >50 km. Alleghanian deformation was influenced by paucity of magmatism and the resistance offered by older stitching plutons. |
| Sommaire | (Résumé en langage clair et simple, non publié)
Une synthèse des mouvements des failles dans le nord de la Nouvelle-Écosse il y a de 370 à 310 millions d'années. |
| GEOSCAN ID | 321847 |
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