Lithoprobe line 55: integration of out-of-plane seismic results with surface structure, metamorphism, and geochronology, and the tectonic evolution of the eastern Grenville Province

Abstract: Lithoprobe line 55, in the Grenville Province of eastern Quebec, provides unusually good control on the three-dimensional (3-D) geometry and structural relationships among the major lithological units there. Archean basement underlies the exposed Proterozoic rocks, along the entire seismic...

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Main Authors: Andrew Hynes, Aphrodite Indares, Toby Rivers, André Gobeil, A Hynes
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
Published: 2000
Subjects:
Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.1035.1227
http://cjes.geoscienceworld.org/content/gscjes/37/2-3/341.full.pdf
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spelling ftciteseerx:oai:CiteSeerX.psu:10.1.1.1035.1227 2023-05-15T18:07:03+02:00 Lithoprobe line 55: integration of out-of-plane seismic results with surface structure, metamorphism, and geochronology, and the tectonic evolution of the eastern Grenville Province Andrew Hynes Aphrodite Indares Toby Rivers André Gobeil A Hynes The Pennsylvania State University CiteSeerX Archives 2000 application/pdf http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.1035.1227 http://cjes.geoscienceworld.org/content/gscjes/37/2-3/341.full.pdf en eng http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.1035.1227 http://cjes.geoscienceworld.org/content/gscjes/37/2-3/341.full.pdf Metadata may be used without restrictions as long as the oai identifier remains attached to it. http://cjes.geoscienceworld.org/content/gscjes/37/2-3/341.full.pdf text 2000 ftciteseerx 2020-02-16T01:14:16Z Abstract: Lithoprobe line 55, in the Grenville Province of eastern Quebec, provides unusually good control on the three-dimensional (3-D) geometry and structural relationships among the major lithological units there. Archean basement underlies the exposed Proterozoic rocks, along the entire seismic line, and there is a lateral ramp in this basement immediately behind a lobate stack of thrust slices of high-pressure metamorphic rocks comprising the Manicouagan Imbricate Zone (MIZ). Integration of the 3-D geometry with P-T and geochronological data allows derivation of a tectonic model for the region. The MIZ was buried to depths >60 km at 1050 Ma. Preservation of its high-pressure assemblages, and the absence of metamorphism at 990 Ma, which is characteristic of lower pressure metamorphic rocks that tectonically overlie them, indicates the MIZ rocks were rapidly unroofed, early in the tectonic history. There were two discrete pulses of crustal thickening during the Grenvillian Orogeny in this region. The first, involving imbrication of Labradorian and Pinwarian rocks that comprised part of southeast Laurentia, culminated in the Ottawan pulse at ca. 1050 Ma, and produced the high-pressure metamorphism of the MIZ. Its effects were rapidly reversed, with extrusion of the MIZ rocks to shallow crustal levels at ca. 1020 Ma. The crust was again thickened, with the Moho subsiding to depths >60 km, in the Rigolet pulse at ca. 990 Ma. The site of extrusion of the MIZ was probably controlled by the subsurface lateral ramp. High geothermal gradients indicate that extrusion may have been aided by lithospheric delamination in the crustal-thickening zone. Résumé : La ligne 55 du projet Lithoprobe, dans la Province de Grenville du Québec oriental, procure un contrôle exceptionnellement utile pour préciser la géométrie tridimensionnelle et établir les relations structurales parmi les plus importantes unités lithologiques de cette région. Le socle archéen est sous-jacent aux roches protérozoïques qui sont exposées tout le ... Text Rigolet Unknown Rigolet ENVELOPE(-58.430,-58.430,54.180,54.180)
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description Abstract: Lithoprobe line 55, in the Grenville Province of eastern Quebec, provides unusually good control on the three-dimensional (3-D) geometry and structural relationships among the major lithological units there. Archean basement underlies the exposed Proterozoic rocks, along the entire seismic line, and there is a lateral ramp in this basement immediately behind a lobate stack of thrust slices of high-pressure metamorphic rocks comprising the Manicouagan Imbricate Zone (MIZ). Integration of the 3-D geometry with P-T and geochronological data allows derivation of a tectonic model for the region. The MIZ was buried to depths >60 km at 1050 Ma. Preservation of its high-pressure assemblages, and the absence of metamorphism at 990 Ma, which is characteristic of lower pressure metamorphic rocks that tectonically overlie them, indicates the MIZ rocks were rapidly unroofed, early in the tectonic history. There were two discrete pulses of crustal thickening during the Grenvillian Orogeny in this region. The first, involving imbrication of Labradorian and Pinwarian rocks that comprised part of southeast Laurentia, culminated in the Ottawan pulse at ca. 1050 Ma, and produced the high-pressure metamorphism of the MIZ. Its effects were rapidly reversed, with extrusion of the MIZ rocks to shallow crustal levels at ca. 1020 Ma. The crust was again thickened, with the Moho subsiding to depths >60 km, in the Rigolet pulse at ca. 990 Ma. The site of extrusion of the MIZ was probably controlled by the subsurface lateral ramp. High geothermal gradients indicate that extrusion may have been aided by lithospheric delamination in the crustal-thickening zone. Résumé : La ligne 55 du projet Lithoprobe, dans la Province de Grenville du Québec oriental, procure un contrôle exceptionnellement utile pour préciser la géométrie tridimensionnelle et établir les relations structurales parmi les plus importantes unités lithologiques de cette région. Le socle archéen est sous-jacent aux roches protérozoïques qui sont exposées tout le ...
author2 The Pennsylvania State University CiteSeerX Archives
format Text
author Andrew Hynes
Aphrodite Indares
Toby Rivers
André Gobeil
A Hynes
spellingShingle Andrew Hynes
Aphrodite Indares
Toby Rivers
André Gobeil
A Hynes
Lithoprobe line 55: integration of out-of-plane seismic results with surface structure, metamorphism, and geochronology, and the tectonic evolution of the eastern Grenville Province
author_facet Andrew Hynes
Aphrodite Indares
Toby Rivers
André Gobeil
A Hynes
author_sort Andrew Hynes
title Lithoprobe line 55: integration of out-of-plane seismic results with surface structure, metamorphism, and geochronology, and the tectonic evolution of the eastern Grenville Province
title_short Lithoprobe line 55: integration of out-of-plane seismic results with surface structure, metamorphism, and geochronology, and the tectonic evolution of the eastern Grenville Province
title_full Lithoprobe line 55: integration of out-of-plane seismic results with surface structure, metamorphism, and geochronology, and the tectonic evolution of the eastern Grenville Province
title_fullStr Lithoprobe line 55: integration of out-of-plane seismic results with surface structure, metamorphism, and geochronology, and the tectonic evolution of the eastern Grenville Province
title_full_unstemmed Lithoprobe line 55: integration of out-of-plane seismic results with surface structure, metamorphism, and geochronology, and the tectonic evolution of the eastern Grenville Province
title_sort lithoprobe line 55: integration of out-of-plane seismic results with surface structure, metamorphism, and geochronology, and the tectonic evolution of the eastern grenville province
publishDate 2000
url http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.1035.1227
http://cjes.geoscienceworld.org/content/gscjes/37/2-3/341.full.pdf
long_lat ENVELOPE(-58.430,-58.430,54.180,54.180)
geographic Rigolet
geographic_facet Rigolet
genre Rigolet
genre_facet Rigolet
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http://cjes.geoscienceworld.org/content/gscjes/37/2-3/341.full.pdf
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