Geology of an Archean Greenstone Belt at Point Lake, Northwest Territories, Canada
Several well-preserved circa 2.6 Ga Archean granite-greenstone belts are exposed in the Slave Province of Northwest Territories, Canada. At Point Lake, a "supracrustal sequence" comprised mainly of mafic volcanic and metasedimentary rocks lies over and east of a granitoid gneissic terrane....
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ftolddominionuni:oai:digitalcommons.odu.edu:oeas_etds-1017 2023-05-15T17:46:33+02:00 Geology of an Archean Greenstone Belt at Point Lake, Northwest Territories, Canada Considine, Patrick Rowan 1995-01-01T08:00:00Z application/pdf https://digitalcommons.odu.edu/oeas_etds/22 https://digitalcommons.odu.edu/cgi/viewcontent.cgi?article=1017&context=oeas_etds unknown ODU Digital Commons https://digitalcommons.odu.edu/oeas_etds/22 https://digitalcommons.odu.edu/cgi/viewcontent.cgi?article=1017&context=oeas_etds In Copyright. URI: http://rightsstatements.org/vocab/InC/1.0/ This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s). OES Theses and Dissertations Archean greenstone belt Point Lake (Canada) Supracrustal sequence Geology text 1995 ftolddominionuni 2023-01-16T18:44:35Z Several well-preserved circa 2.6 Ga Archean granite-greenstone belts are exposed in the Slave Province of Northwest Territories, Canada. At Point Lake, a "supracrustal sequence" comprised mainly of mafic volcanic and metasedimentary rocks lies over and east of a granitoid gneissic terrane. Field and laboratory studies have helped to clarify the petrography and structural relationships of this fold-and-thrust belt. Traditional models have suggested that granite-greenstone belts in the Slave Province are relict continental rifts in which volcanic and sedimentary rocks filled troughs in older sialic crust. However, this study supports a collisional model for the Slave Province, in which oceanic crust and an accretionary wedge were scraped off an eastward subducting plate. The supracrustal sequence consists of a west-verging fold-and-thrust belt which contains metamorphosed graywacke turbidites, ultramafic and gabbroic rocks, pillow basalts, limestone, shale and tuff. A mylonite zone separates the gneissic terrane from the supracrustal sequence. The mylonite is interpreted to be a basal decollement along which the supracrustal sequence was emplaced over gneissic terrane. The sequence of lithologies and structures at Point Lake resembles Phanerozoic collision zones where rocks of oceanic affinity have been emplaced upon continental crust. Text Northwest Territories Old Dominion University: ODU Digital Commons Canada Northwest Territories |
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Old Dominion University: ODU Digital Commons |
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Archean greenstone belt Point Lake (Canada) Supracrustal sequence Geology |
spellingShingle |
Archean greenstone belt Point Lake (Canada) Supracrustal sequence Geology Considine, Patrick Rowan Geology of an Archean Greenstone Belt at Point Lake, Northwest Territories, Canada |
topic_facet |
Archean greenstone belt Point Lake (Canada) Supracrustal sequence Geology |
description |
Several well-preserved circa 2.6 Ga Archean granite-greenstone belts are exposed in the Slave Province of Northwest Territories, Canada. At Point Lake, a "supracrustal sequence" comprised mainly of mafic volcanic and metasedimentary rocks lies over and east of a granitoid gneissic terrane. Field and laboratory studies have helped to clarify the petrography and structural relationships of this fold-and-thrust belt. Traditional models have suggested that granite-greenstone belts in the Slave Province are relict continental rifts in which volcanic and sedimentary rocks filled troughs in older sialic crust. However, this study supports a collisional model for the Slave Province, in which oceanic crust and an accretionary wedge were scraped off an eastward subducting plate. The supracrustal sequence consists of a west-verging fold-and-thrust belt which contains metamorphosed graywacke turbidites, ultramafic and gabbroic rocks, pillow basalts, limestone, shale and tuff. A mylonite zone separates the gneissic terrane from the supracrustal sequence. The mylonite is interpreted to be a basal decollement along which the supracrustal sequence was emplaced over gneissic terrane. The sequence of lithologies and structures at Point Lake resembles Phanerozoic collision zones where rocks of oceanic affinity have been emplaced upon continental crust. |
format |
Text |
author |
Considine, Patrick Rowan |
author_facet |
Considine, Patrick Rowan |
author_sort |
Considine, Patrick Rowan |
title |
Geology of an Archean Greenstone Belt at Point Lake, Northwest Territories, Canada |
title_short |
Geology of an Archean Greenstone Belt at Point Lake, Northwest Territories, Canada |
title_full |
Geology of an Archean Greenstone Belt at Point Lake, Northwest Territories, Canada |
title_fullStr |
Geology of an Archean Greenstone Belt at Point Lake, Northwest Territories, Canada |
title_full_unstemmed |
Geology of an Archean Greenstone Belt at Point Lake, Northwest Territories, Canada |
title_sort |
geology of an archean greenstone belt at point lake, northwest territories, canada |
publisher |
ODU Digital Commons |
publishDate |
1995 |
url |
https://digitalcommons.odu.edu/oeas_etds/22 https://digitalcommons.odu.edu/cgi/viewcontent.cgi?article=1017&context=oeas_etds |
geographic |
Canada Northwest Territories |
geographic_facet |
Canada Northwest Territories |
genre |
Northwest Territories |
genre_facet |
Northwest Territories |
op_source |
OES Theses and Dissertations |
op_relation |
https://digitalcommons.odu.edu/oeas_etds/22 https://digitalcommons.odu.edu/cgi/viewcontent.cgi?article=1017&context=oeas_etds |
op_rights |
In Copyright. URI: http://rightsstatements.org/vocab/InC/1.0/ This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s). |
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