Počet záznamů: 1
Distributed crustal shortening followed by transpressional shearing in the Superior Province, northeastern Canada: A Late Archean analogy to modern accretionary plate margins?
- 1.
SYSNO ASEP 0544127 Druh ASEP J - Článek v odborném periodiku Zařazení RIV J - Článek v odborném periodiku Poddruh J Článek ve WOS Název Distributed crustal shortening followed by transpressional shearing in the Superior Province, northeastern Canada: A Late Archean analogy to modern accretionary plate margins? Tvůrce(i) Žák, J. (CZ)
Tomek, Filip (GLU-S) RID, ORCID, SAI
Svojtka, Martin (GLU-S) SAI, RID, ORCID
Vacek, F. (CZ)
Kachlík, V. (CZ)
Ackerman, Lukáš (GLU-S) RID, SAI, ORCID
Ježek, J. (CZ)
Petronis, M. S. (US)Číslo článku 106322 Zdroj.dok. Precambrian Research. - : Elsevier - ISSN 0301-9268
Roč. 362, 15 August 2021 (2021)Poč.str. 19 s. Jazyk dok. eng - angličtina Země vyd. NL - Nizozemsko Klíč. slova Anisotropy of magnetic susceptibility (AMS) ; Archean tectonics ; Granite ; Pluton ; Superior Province ; Syn-tectonic emplacement Obor OECD Geology CEP GA19-08066S GA ČR - Grantová agentura ČR Způsob publikování Omezený přístup Institucionální podpora GLU-S - RVO:67985831 UT WOS 000684184400034 EID SCOPUS 85111201113 DOI 10.1016/j.precamres.2021.106322 Anotace The Canadian Superior Province has become one of the key test pieces to discuss tectonic processes and mechanisms of crustal growth in the Late Archean. The Province consists of a >2.8 Ga proto-cratonic core intruded by voluminous arc-like plutons and surrounded by a series of narrow, elongate ca. 2.8–2.7 Ga juvenile belts, also referred to as terranes or domains. The terranes seem to wrap around the proto-cratonic core and generally young outward, but the kinematics and geodynamic causes of their assembly remain debated. In this paper, we examine the Radisson pluton in northeastern Qu´ebec, which intruded the southern, outer edge of the presumed magmatic arc (Bienville domain) along its ~WNW–ESE-trending tectonic boundary with the protocratonic crust (La Grande domain). The pluton, dominated by porphyritic monzogranite to quartz monzonite, was emplaced at around 2712 Ma and exhibits complex internal structure resulting from superposed magmatic to solid-state deformations. An early margin-parallel ~WNW–ESE magmatic foliation containing a steep lineation, recognized by the anisotropy of magnetic susceptibility (AMS), is interpreted as recording vertical stretching and horizontal flattening of highly crystallized magma, either due to emplacement and/or pure shear dominated transpression. More widespread, however, is a horizontal lineation within the same foliation that is interpreted as recording post-emplacement, but still syn-magmatic, tectonic strain (~NNE–SSW shortening and boundaryparallel stretching). Upon cooling, localized dextral S–C mylonite zones accommodated further shortening within the pluton whereas undeformed late-stage felsic dikes cross-cut the solid-state fabric at an angle to the pluton margins. We suggest that this structural succession, also reproduced by numerical fabric modeling, is a local-scale signal of a two-stage assembly of the northeastern Superior Province: the frontal, NNE-directed terrane convergence and attachment to the cratonic nucleus, operating in a ‘hot’ regime with voluminous arclike plutonism, was followed by more localized dextral shearing parallel to terrane boundaries. The latter phase is recorded at the proto-craton margin but also in the outboard Abitibi greenstone belt virtually at the same time (ca. 2700–2690 Ma). In combination, the two-stage evolution and similar deformation distributed over a broad region resemble modern large hot orogens formed in a plate-tectonic regime. Pracoviště Geologický ústav Kontakt Jana Popelková, popelkova@gli.cas.cz, Sabina Janíčková, Tel.: 233 087 272 Rok sběru 2022 Elektronická adresa https://www.sciencedirect.com/science/article/pii/S0301926821002503
Počet záznamů: 1