Tectonic implications of early silurian thrust imbrication of the northern exploits subzone, Central Newfoundland

Kusky, Timothy M.; Kidd, William

doi:10.1016/0264-3707(96)00011-7

Cited by 8 publications

(8 citation statements)

References 104 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We suggest that the older western New England magmatic rocks were formed along the western edge of Medial New England and that the Bronson Hill magmatic rocks may be a more easterly exposure of the volcanic arc, or partly a back-arc assemblage located within the earlier Iapetus arc. Important relationships that bear on these questions have been described and interpreted in northern New Brunswick ( van Staal 1994; van Staal & de Roo 1995;van Staal et al 1996van Staal et al , 1998b and Newfoundland (Kusky & Kidd 1996). The Popelogan arc formed over a subduction zone dipping southeast beneath the northwest margin of Miramichi during the Arenig (475-473 Ma), interpreted as the Gander Margin of Composite Avalon.…”

Section: Taconian Magmatic Arcmentioning

confidence: 95%

Paleozoic orogens in New England, USA

Robinson

Tucker²,

Bradley

et al. 1998

GFF

152

131

View full text Add to dashboard Cite

Section: Taconian Magmatic Arcmentioning

confidence: 95%

Paleozoic orogens in New England, USA

Robinson

Tucker²,

Bradley

et al. 1998

GFF

152

131

View full text Add to dashboard Cite

“…These pre-Silurian rocks of the eastern Dunnage Zone are overlain by Sandbian-Katian black shale and Katian-Llandoverian turbiditic sedimentary rocks of the Badger Group (Fig. 2; Kusky and Kidd, 1996;O'Brien, 2003;Waldron et al, 2012), which are in turn overlain unconformably in north-central Newfoundland by bimodal igneous and associated sedimentary rocks of the Botwood Group (Williams, 1962). The easternmost Dunnage Zone exposes a Late Ordovician sequence of low-grade felsic and mafic volcanic and volcaniclastic rocks (Fig.…”

Section: Introductionmentioning

confidence: 99%

Latest Silurian syntectonic sedimentation and magmatism and Early Devonian orogenic gold mineralization, central Newfoundland Appalachians, Canada: Setting, structure, lithogeochemistry, and high-precision U-Pb geochronology

et al. 2022

View full text Add to dashboard Cite

The eastern Dunnage Zone of the central Newfoundland Appalachians hosts Paleozoic orogenic gold mineralization along a northeast-trending, crustal-scale fault corridor that extends for more than 200 km. This orogenic gold system is characterized by polyphase, structurally controlled, quartz vein systems that cut Neoproterozoic granitoid rocks and unconformably overlying syntectonic, polymict conglomerate and associated transitional to calc-alkaline bimodal igneous rocks. High-precision chemical abrasion−isotope dilution−thermal ionization mass spectrometry (CA-ID-TIMS) U-Pb geochronology confirms a widespread, latest Silurian magmatic pulse (422−420 Ma) that is attributed to a transient phase of lithospheric extension resulting from asthenospheric and crustal melting related to slab break-off. Syntectonic conglomerate was deposited as a basal unit during extension-related uplift and erosion that lasted until ca. 418 Ma in north-central Newfoundland. Orogenic gold mineralization associated with syntectonic sedimentation and magmatism is hosted within third-order shear vein systems that form offshoots within a triangle zone−like structural corridor between southeast- and northwest-dipping, second-order fault splays and shear zones. The southeast-dipping fault system formed during northwest migration of the Acadian thrust front, whereas the northwest-dipping faults and shear zones are Salinic structures that were reactivated in the Early Devonian. Primary hydrothermal rutile in the orogenic gold-mineralized quartz veins produced ages of ca. 410 Ma. These ages are consistent with quartz vein emplacement and orogenic gold mineralization as a result of hydrothermal fluid-pressure cycling related to far-field compression and thermal perturbations during the Early Devonian Acadian orogenic cycle. The setting and process evolution of the central Newfoundland gold district are remarkably similar to that of world-class orogenic gold systems of the Canadian Shield.

show abstract

“…This interpretation contrasts with Williams (1993a), but is consistent with our observations and those of other workers (van der Pluijm et al 1993;O'Brien 2003;Dickson 2006;McNicoll et al 2006). The Badger-Botwood unconformity likely corresponds to the main phase of collision-related Salinic deformation (D 1 of Elliott et al 1991;Lafrance and Williams 1992;van der Pluijm et al 1993;Kusky andKidd 1996 andO'Brien 2003) and covers a similar time-span determined for the Salinic collision-related deformation in correlative rocks in central New Brunswick (van Staal et al 2003;Wilson and Kamo 2012).…”

Section: Nature Of the Contact Between Badger And Botwood Groupsmentioning

confidence: 99%

“…This D 1 phase of the Salinic deformation predated eruption and intrusion of the main phases of the Hodges Hill-Charles Lake magmatic suite (Figs. 1, 2), which yielded ages between 435 and 429 Ma (Kusky and Kidd 1996;Dickson 2000;O'Brien 2003, pers. comm.…”

Section: West Of the Red Indian Linementioning

confidence: 99%

“…Elliott et al 1991). Structural transport direction varied, but generally was to the southeast or south taking into account the reorientations caused by younger deformation events (van der Pluijm 1986;Lafrance and Williams 1992;Kusky and Kidd 1996;O'Brien 2003). This D 1 phase of the Salinic deformation predated eruption and intrusion of the main phases of the Hodges Hill-Charles Lake magmatic suite (Figs.…”

Section: West Of the Red Indian Linementioning

confidence: 99%

See 1 more Smart Citation

Time-Transgressive Salinic and Acadian Orogenesis, Magmatism and Old Red Sandstone Sedimentation in Newfoundland

Staal¹,

Zagorevski²,

McNicoll³

et al. 2014

View full text Add to dashboard Cite

We propose an intimate relationship between Silurian terrestrial red bed sedimentation (Old Red Sandstone), slab breakoff-related magmatism and deformation in the Newfoundland Appalachians. Red bed sedimentation started during the Early Silurian, and records the progressive rise of the Salinic mountains in the tectonic hinterland of the orogen. The red beds were mainly deposited in molasse-style foreland basins in front of an east-propagating terminal Salinic deformation front. New U–Pb zircon dating of volcanic rocks interlayered with the Silurian red beds in key structural locations yielded ages ranging between 425 and 418 Ma, which, combined with the existing geochronological database, suggests that the sedimentary rocks are progressively younger from west to east and overstep the accreted Gondwana-derived terranes. We propose that deposition of the red beds is a good proxy for the time of cratonization of the accreted terranes. Eastward migration of the Salinic deformation front was accompanied by eastward-widening of a slab-breakoff-related asthenospheric window. The latter is interpreted to have formed due to a combination of progressive steepening of the down-going plate following entrance of the leading edge of the Gander margin and its eduction. Gander margin eduction (reversed subduction) is proposed to have been instigated by the trench migration of the Acadian coastal arc built upon the trailing edge of the Gander margin, which developed contemporaneously with the Salinic collision. The resultant thinning of the lithosphere beneath the Salinic orogen, built upon the leading edge of the Gander margin immediately prior to the onset of the Early Devonian Acadian orogeny, set the stage for generation of the widespread bloom of Acadian magmatism.SOMMAIRENous proposons qu’il y a eu une relation intime entre la sédimentation des couches rouges continentales au Silurien (vieux-grès-rouges), un magmatisme lié à une rupture de segments de croûte, et la déformation appalachienne à Terre-Neuve. La sédimentation des couches rouges qui a débuté au début du Silurien témoigne du soulèvement progressif des monts saliniques de l’arrière-pays tectonique de l’orogène. Les couches rouges se sont déposées sous forme de molasses dans des bassins d’avant-pays, à l’avant du front de déformation salinique terminale qui se déployait vers l’est. De nouvelles datations U-Pb sur zircon de roches volcaniques interstratifiées avec des couches rouges siluriennes en des lieux structurels stratégiques montrent des âges qui varient entre 425 Ma et 418 Ma, ce qui, combiné aux bases de données géochronologiques existantes permet de penser que les roches sédimentaires sont progressivement plus jeunes d’ouest en est, et qu’elles surplombent les terranes accrétés du Gondwana. Nous suggérons que les couches rouges sont de bons indicateurs temporels de la cratonisation des terranes accrétés. La migration vers l’est du front de la déformation salinique a été accompagnée par un élargissement vers l’est d’une fenêtre asthénosphérique liée à une rupture de la croûte. Cette dernière aurait été provoquée par la combinaison de l’enfoncement progressif de la plaque qui a suivi l’entrée du bord d’attaque de la marge de Gander, et son éduction. Nous proposons que l’éduction (l’inverse de la subduction) de la marge de Gander a été provoquée par la migration de la fosse tectonique côtière acadienne, induite par la migration du bord d’attaque de la marge de Gander, contemporaine de la collision salinique. L’amincissement de la lithosphère sous l’orogène salinique qui en a résulté, et qui s’est déployé au bord d’attaque de la marge de Gander juste avant l’enclenchement de l’orogénie acadienne au début du Dévonien, a préparé le terrain du déploiement à grande échelle du magmatisme acadien.

show abstract

Tectonic implications of early silurian thrust imbrication of the northern exploits subzone, Central Newfoundland

Abstract: Abstract-Central

Cited by 8 publications

References 104 publications

Paleozoic orogens in New England, USA

Paleozoic orogens in New England, USA

Latest Silurian syntectonic sedimentation and magmatism and Early Devonian orogenic gold mineralization, central Newfoundland Appalachians, Canada: Setting, structure, lithogeochemistry, and high-precision U-Pb geochronology

Time-Transgressive Salinic and Acadian Orogenesis, Magmatism and Old Red Sandstone Sedimentation in Newfoundland

Contact Info

Product

Resources

About