A revised geochronology for the Blekinge Province, southern Sweden
(2006) In GFF 128. p.287-302- Abstract
- Zircon grains from nine samples of metavolcanic rocks, gneisses, granitoids and migmatites from the Blekinge Province in southeasternmost Sweden have been dated by U-Pb using ion microprobe. The results suggest that most of the Blekinge bedrock was formed within a narrow time interval of 1.77-1.75 Ga, including the Vastana supracrustal formation and 'coastal gneisses' previously dated to c. 1.70 Ga. One sample, the 1.81 Ga Nattraby gneissic granite, appears to represent a sliver of slightly older proto-crust. An age of c. 1.75 Ga for an aplitic granite crosscutting the deformed Tving granitoids in eastern Blekinge brackets their deformation to between 1.77 and 1.75 Ga, whereas zircon grains of similar age from a migmatite neosome at Lindo... (More)
- Zircon grains from nine samples of metavolcanic rocks, gneisses, granitoids and migmatites from the Blekinge Province in southeasternmost Sweden have been dated by U-Pb using ion microprobe. The results suggest that most of the Blekinge bedrock was formed within a narrow time interval of 1.77-1.75 Ga, including the Vastana supracrustal formation and 'coastal gneisses' previously dated to c. 1.70 Ga. One sample, the 1.81 Ga Nattraby gneissic granite, appears to represent a sliver of slightly older proto-crust. An age of c. 1.75 Ga for an aplitic granite crosscutting the deformed Tving granitoids in eastern Blekinge brackets their deformation to between 1.77 and 1.75 Ga, whereas zircon grains of similar age from a migmatite neosome at Lindo may be inherited, making the result inconclusive. Thin metamorphic zircon overgrowths and resetting of the U-Pb system in titanite indicate a regional tectonothermal event at 1.45 to 1.40 Ga, accompanying the intrusion of the Karlshamn-type granites. The crust of the Blekinge Province thus was formed at 1.77-1.75 Ga from relatively juvenile sources in a subduction-related environment along the southern edge of Fennoscandia. It was deformed and partly uplifted relative to the undeformed TIB-1 granitoids of the Smaland block further north, prior to the intrusion of the Karlshamn-type granites at 1.45 Ga. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/677370
- author
- Johansson, Ake ; Bogdanova, Svetlana LU and Cecys, Audrius LU
- organization
- publishing date
- 2006
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- Blekinge, zircon, U-Pb, ion microprobe, titanite, Sm-Nd, Rb-Sr, vastana, formation, Tving granitoids, coastal gneiss, southern Sweden
- in
- GFF
- volume
- 128
- pages
- 287 - 302
- publisher
- Taylor & Francis
- external identifiers
-
- wos:000243752400002
- scopus:33846543673
- ISSN
- 2000-0863
- language
- English
- LU publication?
- yes
- id
- 46957a54-6576-4a79-a4f8-464befdedd85 (old id 677370)
- alternative location
- http://www.gff-online.se/site/article.asp?articleID=895
- date added to LUP
- 2016-04-01 12:15:26
- date last changed
- 2022-04-21 04:53:18
@article{46957a54-6576-4a79-a4f8-464befdedd85,
abstract = {{Zircon grains from nine samples of metavolcanic rocks, gneisses, granitoids and migmatites from the Blekinge Province in southeasternmost Sweden have been dated by U-Pb using ion microprobe. The results suggest that most of the Blekinge bedrock was formed within a narrow time interval of 1.77-1.75 Ga, including the Vastana supracrustal formation and 'coastal gneisses' previously dated to c. 1.70 Ga. One sample, the 1.81 Ga Nattraby gneissic granite, appears to represent a sliver of slightly older proto-crust. An age of c. 1.75 Ga for an aplitic granite crosscutting the deformed Tving granitoids in eastern Blekinge brackets their deformation to between 1.77 and 1.75 Ga, whereas zircon grains of similar age from a migmatite neosome at Lindo may be inherited, making the result inconclusive. Thin metamorphic zircon overgrowths and resetting of the U-Pb system in titanite indicate a regional tectonothermal event at 1.45 to 1.40 Ga, accompanying the intrusion of the Karlshamn-type granites. The crust of the Blekinge Province thus was formed at 1.77-1.75 Ga from relatively juvenile sources in a subduction-related environment along the southern edge of Fennoscandia. It was deformed and partly uplifted relative to the undeformed TIB-1 granitoids of the Smaland block further north, prior to the intrusion of the Karlshamn-type granites at 1.45 Ga.}},
author = {{Johansson, Ake and Bogdanova, Svetlana and Cecys, Audrius}},
issn = {{2000-0863}},
keywords = {{Blekinge; zircon; U-Pb; ion microprobe; titanite; Sm-Nd; Rb-Sr; vastana; formation; Tving granitoids; coastal gneiss; southern Sweden}},
language = {{eng}},
pages = {{287--302}},
publisher = {{Taylor & Francis}},
series = {{GFF}},
title = {{A revised geochronology for the Blekinge Province, southern Sweden}},
url = {{http://www.gff-online.se/site/article.asp?articleID=895}},
volume = {{128}},
year = {{2006}},
}