| Title | 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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| Author | Piper, D J W ;
Pe-Piper, G |
| Source | Pannotia to Pangaea: Neoproterozoic and Paleozoic orogenic cycles in the circum-Atlantic region; by Murphy, J B (ed.); Strachan, R A (ed.); Quesada, C (ed.); Geological Society, Special Publication vol.
503, 2020 p. 1-20, https://doi.org/10.1144/SP503-2019-239 |
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| Year | 2020 |
| Alt Series | Natural Resources Canada, Contribution Series 20190545 |
| Publisher | Geological Society of London |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| File format | pdf |
| Province | Nova Scotia |
| NTS | 11D/05; 11D/06; 11D/11; 11D/12; 21A/07; 21A/08; 21A/09; 21A/10 |
| Area | Cobequid Highlands; Canada |
| Lat/Long WENS | -65.0000 -63.0000 45.5833 45.3333 |
| Subjects | tectonics; paleontology; stratigraphy; geochemistry; geochronology; Science and Technology; Nature and Environment; tectonic evolution; orogenies; shearing; deformation; faulting; displacement; thermal
history; magmatism; intrusions; dykes; plutons; volcanism; bedrock geology; structural features; shear zones; fault zones; faults; faults, strike-slip; grabens; lithology; igneous rocks; intrusive rocks; gabbros; granites; sedimentary rocks;
biostratigraphy; provenance; isotopic studies; neodymium; radiometric dates; Appalachian Orogen; Acadian Orogeny; Alleghanian Orogeny; Rheic Ocean; Pangea; Cobequid Shear Zone; Laurentia; Minas Fault Zone; Cobequid-Chedabucto Fault; Horton Group;
Kirkhill Fault; Rockland Brook Fault; Cobequid Fault; Portapique Fault; Millvale Fault; Spicers Cove Fault; Lynn Mountain Fault; Fountain Lake Group; Phanerozoic; Paleozoic; Permian; Carboniferous; Devonian |
| Illustrations | geoscientific sketch maps; geochronological charts; stratigraphic sections; schematic cross-sections; photographs; photomicrographs |
| Program | GSC Atlantic Division |
| Released | 2020 05 20 |
| Abstract | 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. |
| Summary | (Plain Language Summary, not published)
A synthesis of movement on faults in northern Nova Scotia between 370 and 310 million years ago. |
| GEOSCAN ID | 321847 |
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