Geometry of the allochthonous Daly Bay Complex, Northwest Territories: a model constrained by geology and a three-dimensional gravity interpretation
The Daly Bay Complex is one of several metamorphic complexes making up the Aqxarneq gneisses north of Chesterfield Inlet in central District of Keewatin. Granulite-facies metamorphism (0.55 GPa, 750 °C) and ductile deformation have affected all of the rocks in the complex. A 1–15 km wide, inward-dip...
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crcansciencepubl:10.1139/e95-105 2023-12-17T10:27:39+01:00 Geometry of the allochthonous Daly Bay Complex, Northwest Territories: a model constrained by geology and a three-dimensional gravity interpretation Gordon, Terence M. Lawton, Donald C. 1995 http://dx.doi.org/10.1139/e95-105 http://www.nrcresearchpress.com/doi/pdf/10.1139/e95-105 en eng Canadian Science Publishing http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining Canadian Journal of Earth Sciences volume 32, issue 9, page 1292-1302 ISSN 0008-4077 1480-3313 General Earth and Planetary Sciences journal-article 1995 crcansciencepubl https://doi.org/10.1139/e95-105 2023-11-19T13:39:04Z The Daly Bay Complex is one of several metamorphic complexes making up the Aqxarneq gneisses north of Chesterfield Inlet in central District of Keewatin. Granulite-facies metamorphism (0.55 GPa, 750 °C) and ductile deformation have affected all of the rocks in the complex. A 1–15 km wide, inward-dipping, ductile shear zone forms the outer part of the complex and contains strongly deformed equivalents of rocks in the core. Mesoscopic structures and metamorphic mineralogy suggest the Daly Bay Complex was emplaced into the surrounding lower grade rocks by northward-directed thrusting. A three-dimensional gravity model, constrained by structural observations and 1091 surface density measurements, shows that the relatively dense rocks of the complex form a spoon-shaped structure with a long axis trending northwest–southeast. It is approximately 50 km by 120 km in lateral extent and reaches a maximum depth of about 9 km. The thin-skinned geometry of the Daly Bay Complex supports the notion that the crust in central Keewatin between the Daly Bay Complex and Baker Lake comprises a series of undulating imbricated gneiss sheets of middle and lower crustal material, which were juxtaposed by a major tectonic event sometime between 2.5 and 1.9 Ga. The interpreted basal décollement is comparable to seismic features in many orogens, and a predictable consequence of increased ductility with depth in the crust. Article in Journal/Newspaper Baker Lake Chesterfield Inlet Daly Bay Keewatin Northwest Territories Canadian Science Publishing (via Crossref) Northwest Territories Daly ENVELOPE(63.761,63.761,-67.513,-67.513) Chesterfield Inlet ENVELOPE(-90.705,-90.705,63.342,63.342) Daly Bay ENVELOPE(-89.750,-89.750,64.001,64.001) Canadian Journal of Earth Sciences 32 9 1292 1302 |
institution |
Open Polar |
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Canadian Science Publishing (via Crossref) |
op_collection_id |
crcansciencepubl |
language |
English |
topic |
General Earth and Planetary Sciences |
spellingShingle |
General Earth and Planetary Sciences Gordon, Terence M. Lawton, Donald C. Geometry of the allochthonous Daly Bay Complex, Northwest Territories: a model constrained by geology and a three-dimensional gravity interpretation |
topic_facet |
General Earth and Planetary Sciences |
description |
The Daly Bay Complex is one of several metamorphic complexes making up the Aqxarneq gneisses north of Chesterfield Inlet in central District of Keewatin. Granulite-facies metamorphism (0.55 GPa, 750 °C) and ductile deformation have affected all of the rocks in the complex. A 1–15 km wide, inward-dipping, ductile shear zone forms the outer part of the complex and contains strongly deformed equivalents of rocks in the core. Mesoscopic structures and metamorphic mineralogy suggest the Daly Bay Complex was emplaced into the surrounding lower grade rocks by northward-directed thrusting. A three-dimensional gravity model, constrained by structural observations and 1091 surface density measurements, shows that the relatively dense rocks of the complex form a spoon-shaped structure with a long axis trending northwest–southeast. It is approximately 50 km by 120 km in lateral extent and reaches a maximum depth of about 9 km. The thin-skinned geometry of the Daly Bay Complex supports the notion that the crust in central Keewatin between the Daly Bay Complex and Baker Lake comprises a series of undulating imbricated gneiss sheets of middle and lower crustal material, which were juxtaposed by a major tectonic event sometime between 2.5 and 1.9 Ga. The interpreted basal décollement is comparable to seismic features in many orogens, and a predictable consequence of increased ductility with depth in the crust. |
format |
Article in Journal/Newspaper |
author |
Gordon, Terence M. Lawton, Donald C. |
author_facet |
Gordon, Terence M. Lawton, Donald C. |
author_sort |
Gordon, Terence M. |
title |
Geometry of the allochthonous Daly Bay Complex, Northwest Territories: a model constrained by geology and a three-dimensional gravity interpretation |
title_short |
Geometry of the allochthonous Daly Bay Complex, Northwest Territories: a model constrained by geology and a three-dimensional gravity interpretation |
title_full |
Geometry of the allochthonous Daly Bay Complex, Northwest Territories: a model constrained by geology and a three-dimensional gravity interpretation |
title_fullStr |
Geometry of the allochthonous Daly Bay Complex, Northwest Territories: a model constrained by geology and a three-dimensional gravity interpretation |
title_full_unstemmed |
Geometry of the allochthonous Daly Bay Complex, Northwest Territories: a model constrained by geology and a three-dimensional gravity interpretation |
title_sort |
geometry of the allochthonous daly bay complex, northwest territories: a model constrained by geology and a three-dimensional gravity interpretation |
publisher |
Canadian Science Publishing |
publishDate |
1995 |
url |
http://dx.doi.org/10.1139/e95-105 http://www.nrcresearchpress.com/doi/pdf/10.1139/e95-105 |
long_lat |
ENVELOPE(63.761,63.761,-67.513,-67.513) ENVELOPE(-90.705,-90.705,63.342,63.342) ENVELOPE(-89.750,-89.750,64.001,64.001) |
geographic |
Northwest Territories Daly Chesterfield Inlet Daly Bay |
geographic_facet |
Northwest Territories Daly Chesterfield Inlet Daly Bay |
genre |
Baker Lake Chesterfield Inlet Daly Bay Keewatin Northwest Territories |
genre_facet |
Baker Lake Chesterfield Inlet Daly Bay Keewatin Northwest Territories |
op_source |
Canadian Journal of Earth Sciences volume 32, issue 9, page 1292-1302 ISSN 0008-4077 1480-3313 |
op_rights |
http://www.nrcresearchpress.com/page/about/CorporateTextAndDataMining |
op_doi |
https://doi.org/10.1139/e95-105 |
container_title |
Canadian Journal of Earth Sciences |
container_volume |
32 |
container_issue |
9 |
container_start_page |
1292 |
op_container_end_page |
1302 |
_version_ |
1785579562836426752 |