The Tornio layered intrusion - a recently discovered intrusion with chromitite horizons in Northern Finland
In the 1960's chromite boulders were found in the area between the Kemi chromium mine and the town of Tornio. In 1979 after many years of prospecting a layered intrusion with thin chromitite layers was found northeast of the town of Tornio. The stratified sill-like intrusion is situated between...
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Geological Society of Finland
1982
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ftdoajarticles:oai:doaj.org/article:347a953a73c54ef3b862ce77c74961d7 2023-05-15T17:42:34+02:00 The Tornio layered intrusion - a recently discovered intrusion with chromitite horizons in Northern Finland K. Söderholm O. Inkinen 1982-12-01T00:00:00Z https://doi.org/10.17741/bgsf/54.1-2.002 https://doaj.org/article/347a953a73c54ef3b862ce77c74961d7 EN eng Geological Society of Finland http://www.geologinenseura.fi/bulletin/Volume54/sgs_bt_054_pages_015_024.pdf https://doaj.org/toc/0367-5211 https://doaj.org/toc/1799-4632 doi:10.17741/bgsf/54.1-2.002 0367-5211 1799-4632 https://doaj.org/article/347a953a73c54ef3b862ce77c74961d7 Bulletin of the Geological Society of Finland, Vol 54, Iss 1-2, Pp 15-24 (1982) Geology QE1-996.5 article 1982 ftdoajarticles https://doi.org/10.17741/bgsf/54.1-2.002 2022-12-31T04:22:23Z In the 1960's chromite boulders were found in the area between the Kemi chromium mine and the town of Tornio. In 1979 after many years of prospecting a layered intrusion with thin chromitite layers was found northeast of the town of Tornio. The stratified sill-like intrusion is situated between the Presvecokarelian basement complex and the Peräpohja schist formation. The age of the intrusion is very likely the same as that of the Kemi and Penikat intrusions, that is 2 440 Ma. The rocks both below and immediately above these intrusions are older than 2 440 Ma. The length of the intrusion is at least 6 km and it extends into Sweden. Several thin chromitite layers have been intersected by drilling, all in the ultramafic unit. The Cr2O3 content of the chromitite layers varies between 26 and 32%, the FeOtot content between 22 and 28% and the Cr/Fe ratio between 0.9 and 1.2. The chromites are Fe-rich and Mg-poor averaging 43 % Cr2O3. The chromite deposit of the Tornio intrusion, like those of the Kemi and Penikat intrusions, is of the stratiform type. The Tornio and Penikat intrusions resemble each other as do the compositions of their chromites. Article in Journal/Newspaper Northern Finland Directory of Open Access Journals: DOAJ Articles Tornio ENVELOPE(24.147,24.147,65.848,65.848) Bulletin of the Geological Society of Finland 54 1-2 15 24 |
institution |
Open Polar |
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Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Geology QE1-996.5 |
spellingShingle |
Geology QE1-996.5 K. Söderholm O. Inkinen The Tornio layered intrusion - a recently discovered intrusion with chromitite horizons in Northern Finland |
topic_facet |
Geology QE1-996.5 |
description |
In the 1960's chromite boulders were found in the area between the Kemi chromium mine and the town of Tornio. In 1979 after many years of prospecting a layered intrusion with thin chromitite layers was found northeast of the town of Tornio. The stratified sill-like intrusion is situated between the Presvecokarelian basement complex and the Peräpohja schist formation. The age of the intrusion is very likely the same as that of the Kemi and Penikat intrusions, that is 2 440 Ma. The rocks both below and immediately above these intrusions are older than 2 440 Ma. The length of the intrusion is at least 6 km and it extends into Sweden. Several thin chromitite layers have been intersected by drilling, all in the ultramafic unit. The Cr2O3 content of the chromitite layers varies between 26 and 32%, the FeOtot content between 22 and 28% and the Cr/Fe ratio between 0.9 and 1.2. The chromites are Fe-rich and Mg-poor averaging 43 % Cr2O3. The chromite deposit of the Tornio intrusion, like those of the Kemi and Penikat intrusions, is of the stratiform type. The Tornio and Penikat intrusions resemble each other as do the compositions of their chromites. |
format |
Article in Journal/Newspaper |
author |
K. Söderholm O. Inkinen |
author_facet |
K. Söderholm O. Inkinen |
author_sort |
K. Söderholm |
title |
The Tornio layered intrusion - a recently discovered intrusion with chromitite horizons in Northern Finland |
title_short |
The Tornio layered intrusion - a recently discovered intrusion with chromitite horizons in Northern Finland |
title_full |
The Tornio layered intrusion - a recently discovered intrusion with chromitite horizons in Northern Finland |
title_fullStr |
The Tornio layered intrusion - a recently discovered intrusion with chromitite horizons in Northern Finland |
title_full_unstemmed |
The Tornio layered intrusion - a recently discovered intrusion with chromitite horizons in Northern Finland |
title_sort |
tornio layered intrusion - a recently discovered intrusion with chromitite horizons in northern finland |
publisher |
Geological Society of Finland |
publishDate |
1982 |
url |
https://doi.org/10.17741/bgsf/54.1-2.002 https://doaj.org/article/347a953a73c54ef3b862ce77c74961d7 |
long_lat |
ENVELOPE(24.147,24.147,65.848,65.848) |
geographic |
Tornio |
geographic_facet |
Tornio |
genre |
Northern Finland |
genre_facet |
Northern Finland |
op_source |
Bulletin of the Geological Society of Finland, Vol 54, Iss 1-2, Pp 15-24 (1982) |
op_relation |
http://www.geologinenseura.fi/bulletin/Volume54/sgs_bt_054_pages_015_024.pdf https://doaj.org/toc/0367-5211 https://doaj.org/toc/1799-4632 doi:10.17741/bgsf/54.1-2.002 0367-5211 1799-4632 https://doaj.org/article/347a953a73c54ef3b862ce77c74961d7 |
op_doi |
https://doi.org/10.17741/bgsf/54.1-2.002 |
container_title |
Bulletin of the Geological Society of Finland |
container_volume |
54 |
container_issue |
1-2 |
container_start_page |
15 |
op_container_end_page |
24 |
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1766144454416138240 |