Evidence for spreading in the lower Kam Group of the Yellowknife greenstone belt: Implications for Archaean basin evolution in the Slave Province
The Yellowknife greenstone belt is the western margin of an Archean turbidite-filled basin bordered on the east by the Cameron River and Beaulieu River volcanic belts (Henderson, 1981; Lambert, 1982). This model implies that rifting was entirely ensialic and did not proceed beyond the graben stage....
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ftnasantrs:oai:casi.ntrs.nasa.gov:19860013638 2023-05-15T18:45:39+02:00 Evidence for spreading in the lower Kam Group of the Yellowknife greenstone belt: Implications for Archaean basin evolution in the Slave Province Padgham, W. A. Helmstaedt, H. Unclassified, Unlimited, Publicly available JAN 1, 1986 application/pdf http://hdl.handle.net/2060/19860013638 unknown Document ID: 19860013638 Accession ID: 86N23109 http://hdl.handle.net/2060/19860013638 No Copyright CASI GEOPHYSICS Lunar and Planetary Inst. Workshop on the Tectonic Evolution of Greenstone Belts; p 55-58 1986 ftnasantrs 2016-06-11T22:52:25Z The Yellowknife greenstone belt is the western margin of an Archean turbidite-filled basin bordered on the east by the Cameron River and Beaulieu River volcanic belts (Henderson, 1981; Lambert, 1982). This model implies that rifting was entirely ensialic and did not proceed beyond the graben stage. Volcanism is assumed to have been restricted to the boundary faults, and the basin was floored by a downfaulted granitic basement. On the other hand, the enormous thickness of submarine volcanic rocks and the presence of a spreading complex at the base of the Kam Group suggest that volcanic rocks were much more widespread than indicated by their present distribution. Rather than resembling volcanic sequences in intracratonic graben structures, the Kam Group and its tectonic setting within the Yellowknife greenstone belt have greater affinities to the Rocas Verdes of southern Chile, Mesozoic ophiolites, that were formed in an arc-related marginal basin setting. The similarities of these ophiolites with some Archean volcanic sequences was previously recognized, and served as basis for their marginal-basin model of greenstone belts. The discovery of a multiple and sheeted dike complex in the Kam Group confirms that features typical of Phanerozoic ophiolites are indeed preserved in some greenstone belts and provides further field evidence in support of such a model. Other/Unknown Material Yellowknife NASA Technical Reports Server (NTRS) Yellowknife Rocas ENVELOPE(-56.948,-56.948,-63.398,-63.398) Beaulieu River ENVELOPE(-113.186,-113.186,62.050,62.050) |
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NASA Technical Reports Server (NTRS) |
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topic |
GEOPHYSICS |
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GEOPHYSICS Padgham, W. A. Helmstaedt, H. Evidence for spreading in the lower Kam Group of the Yellowknife greenstone belt: Implications for Archaean basin evolution in the Slave Province |
topic_facet |
GEOPHYSICS |
description |
The Yellowknife greenstone belt is the western margin of an Archean turbidite-filled basin bordered on the east by the Cameron River and Beaulieu River volcanic belts (Henderson, 1981; Lambert, 1982). This model implies that rifting was entirely ensialic and did not proceed beyond the graben stage. Volcanism is assumed to have been restricted to the boundary faults, and the basin was floored by a downfaulted granitic basement. On the other hand, the enormous thickness of submarine volcanic rocks and the presence of a spreading complex at the base of the Kam Group suggest that volcanic rocks were much more widespread than indicated by their present distribution. Rather than resembling volcanic sequences in intracratonic graben structures, the Kam Group and its tectonic setting within the Yellowknife greenstone belt have greater affinities to the Rocas Verdes of southern Chile, Mesozoic ophiolites, that were formed in an arc-related marginal basin setting. The similarities of these ophiolites with some Archean volcanic sequences was previously recognized, and served as basis for their marginal-basin model of greenstone belts. The discovery of a multiple and sheeted dike complex in the Kam Group confirms that features typical of Phanerozoic ophiolites are indeed preserved in some greenstone belts and provides further field evidence in support of such a model. |
format |
Other/Unknown Material |
author |
Padgham, W. A. Helmstaedt, H. |
author_facet |
Padgham, W. A. Helmstaedt, H. |
author_sort |
Padgham, W. A. |
title |
Evidence for spreading in the lower Kam Group of the Yellowknife greenstone belt: Implications for Archaean basin evolution in the Slave Province |
title_short |
Evidence for spreading in the lower Kam Group of the Yellowknife greenstone belt: Implications for Archaean basin evolution in the Slave Province |
title_full |
Evidence for spreading in the lower Kam Group of the Yellowknife greenstone belt: Implications for Archaean basin evolution in the Slave Province |
title_fullStr |
Evidence for spreading in the lower Kam Group of the Yellowknife greenstone belt: Implications for Archaean basin evolution in the Slave Province |
title_full_unstemmed |
Evidence for spreading in the lower Kam Group of the Yellowknife greenstone belt: Implications for Archaean basin evolution in the Slave Province |
title_sort |
evidence for spreading in the lower kam group of the yellowknife greenstone belt: implications for archaean basin evolution in the slave province |
publishDate |
1986 |
url |
http://hdl.handle.net/2060/19860013638 |
op_coverage |
Unclassified, Unlimited, Publicly available |
long_lat |
ENVELOPE(-56.948,-56.948,-63.398,-63.398) ENVELOPE(-113.186,-113.186,62.050,62.050) |
geographic |
Yellowknife Rocas Beaulieu River |
geographic_facet |
Yellowknife Rocas Beaulieu River |
genre |
Yellowknife |
genre_facet |
Yellowknife |
op_source |
CASI |
op_relation |
Document ID: 19860013638 Accession ID: 86N23109 http://hdl.handle.net/2060/19860013638 |
op_rights |
No Copyright |
_version_ |
1766236770165325824 |