Basement Gneiss doming the Uppermost Allochthon in the Bogøy area of Steigen, Nordland, Norway.
Steigen lies geographically within the Uppermost Allochthon, which was emplacedduring the Scandian phase of the Caledonian orogeny. A tectonized boundaryseparates a basement culmination of Precambrian granite-gneisses from youngercover metasediments. The latter comprise marbles, quartzites, amphibol...
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ftnorgesgu:oai:openarchive.ngu.no:11250/2674202 2023-05-15T17:24:35+02:00 Basement Gneiss doming the Uppermost Allochthon in the Bogøy area of Steigen, Nordland, Norway. Speedyman, David L. 20301 Steigen 1989 application/pdf https://hdl.handle.net/11250/2674202 eng eng NGU Bulletin (414) https://hdl.handle.net/11250/2674202 Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no CC-BY 37-47 FOLDNING GNEIS GRANITT KALEDONSKE FJELLKJEDE KARTLEGGING STRUKTURGEOLOGI TEKTONIKK Journal article 1989 ftnorgesgu 2022-07-03T15:27:12Z Steigen lies geographically within the Uppermost Allochthon, which was emplacedduring the Scandian phase of the Caledonian orogeny. A tectonized boundaryseparates a basement culmination of Precambrian granite-gneisses from youngercover metasediments. The latter comprise marbles, quartzites, amphibolites andpelitic to semipelitic schists, which have been divided informally into fourgroups. Caledonian metamorphism reached a peak in the almandine-amphibolitefacies during the second main deformation phase (D2), with some retrograderecrystallization after D2. An early deformation phase (D1) is indicated by thepreservation of discordant fabrics within porphyroblasts, while the majority offolds are contemporaneous with the formation of the penetrative schistosity(D2). D2 fabrics and fold-axes have been folded into a large D3 antiform whichdeveloped during uprise of the basement geniss culmination late in the orogeny.The granite-gneiss basement exhibits a foliation which is parallel to the base-ment's contact with the metasediments. The geochemistry of the gneisses is verysimilar to that of other basement gneisses in Nordland and to rapakivigranites.The gneisses are considered to be Proterozoic rapakivi granites whichrose diapirically during the Caledonian orogeny, causing updoming anddeformation of the metasediments. 35188 Article in Journal/Newspaper Nordland Nordland Steigen Nordland NGU Open Archive (Geological Survey of Norway) Norway |
institution |
Open Polar |
collection |
NGU Open Archive (Geological Survey of Norway) |
op_collection_id |
ftnorgesgu |
language |
English |
topic |
FOLDNING GNEIS GRANITT KALEDONSKE FJELLKJEDE KARTLEGGING STRUKTURGEOLOGI TEKTONIKK |
spellingShingle |
FOLDNING GNEIS GRANITT KALEDONSKE FJELLKJEDE KARTLEGGING STRUKTURGEOLOGI TEKTONIKK Speedyman, David L. Basement Gneiss doming the Uppermost Allochthon in the Bogøy area of Steigen, Nordland, Norway. |
topic_facet |
FOLDNING GNEIS GRANITT KALEDONSKE FJELLKJEDE KARTLEGGING STRUKTURGEOLOGI TEKTONIKK |
description |
Steigen lies geographically within the Uppermost Allochthon, which was emplacedduring the Scandian phase of the Caledonian orogeny. A tectonized boundaryseparates a basement culmination of Precambrian granite-gneisses from youngercover metasediments. The latter comprise marbles, quartzites, amphibolites andpelitic to semipelitic schists, which have been divided informally into fourgroups. Caledonian metamorphism reached a peak in the almandine-amphibolitefacies during the second main deformation phase (D2), with some retrograderecrystallization after D2. An early deformation phase (D1) is indicated by thepreservation of discordant fabrics within porphyroblasts, while the majority offolds are contemporaneous with the formation of the penetrative schistosity(D2). D2 fabrics and fold-axes have been folded into a large D3 antiform whichdeveloped during uprise of the basement geniss culmination late in the orogeny.The granite-gneiss basement exhibits a foliation which is parallel to the base-ment's contact with the metasediments. The geochemistry of the gneisses is verysimilar to that of other basement gneisses in Nordland and to rapakivigranites.The gneisses are considered to be Proterozoic rapakivi granites whichrose diapirically during the Caledonian orogeny, causing updoming anddeformation of the metasediments. 35188 |
format |
Article in Journal/Newspaper |
author |
Speedyman, David L. |
author_facet |
Speedyman, David L. |
author_sort |
Speedyman, David L. |
title |
Basement Gneiss doming the Uppermost Allochthon in the Bogøy area of Steigen, Nordland, Norway. |
title_short |
Basement Gneiss doming the Uppermost Allochthon in the Bogøy area of Steigen, Nordland, Norway. |
title_full |
Basement Gneiss doming the Uppermost Allochthon in the Bogøy area of Steigen, Nordland, Norway. |
title_fullStr |
Basement Gneiss doming the Uppermost Allochthon in the Bogøy area of Steigen, Nordland, Norway. |
title_full_unstemmed |
Basement Gneiss doming the Uppermost Allochthon in the Bogøy area of Steigen, Nordland, Norway. |
title_sort |
basement gneiss doming the uppermost allochthon in the bogøy area of steigen, nordland, norway. |
publishDate |
1989 |
url |
https://hdl.handle.net/11250/2674202 |
op_coverage |
20301 Steigen |
geographic |
Norway |
geographic_facet |
Norway |
genre |
Nordland Nordland Steigen Nordland |
genre_facet |
Nordland Nordland Steigen Nordland |
op_source |
37-47 |
op_relation |
NGU Bulletin (414) https://hdl.handle.net/11250/2674202 |
op_rights |
Navngivelse 4.0 Internasjonal http://creativecommons.org/licenses/by/4.0/deed.no |
op_rightsnorm |
CC-BY |
_version_ |
1766115669024178176 |