Zones of PGE–Chromite Mineralization in Relation to Crystallization of the Pados-Tundra Ultramafic Complex, Serpentinite Belt, Kola Peninsula, Russia
The lopolithic Pados-Tundra layered complex, the largest member of the Serpentinite belt–Tulppio belt (SB–TB) megastructure in the Fennoscandian Shield, is characterized by (1) highly magnesian compositions of comagmatic dunite–harzburgite–orthopyroxenite, with primitive levels of high-field-strengt...
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MDPI AG
2021
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ftdoajarticles:oai:doaj.org/article:dfdc06c26cf34d7ebba4cf37fb3bd645 2024-01-07T09:43:13+01:00 Zones of PGE–Chromite Mineralization in Relation to Crystallization of the Pados-Tundra Ultramafic Complex, Serpentinite Belt, Kola Peninsula, Russia Andrei Y. Barkov Andrey A. Nikiforov Larisa P. Barkova Vladimir N. Korolyuk Robert F. Martin 2021-01-01T00:00:00Z https://doi.org/10.3390/min11010068 https://doaj.org/article/dfdc06c26cf34d7ebba4cf37fb3bd645 EN eng MDPI AG https://www.mdpi.com/2075-163X/11/1/68 https://doaj.org/toc/2075-163X doi:10.3390/min11010068 2075-163X https://doaj.org/article/dfdc06c26cf34d7ebba4cf37fb3bd645 Minerals, Vol 11, Iss 1, p 68 (2021) chromite mineralization ultramafic complexes hypabyssal intrusions highly magnesian magma komatiites oxidation Mineralogy QE351-399.2 article 2021 ftdoajarticles https://doi.org/10.3390/min11010068 2023-12-10T01:46:26Z The lopolithic Pados-Tundra layered complex, the largest member of the Serpentinite belt–Tulppio belt (SB–TB) megastructure in the Fennoscandian Shield, is characterized by (1) highly magnesian compositions of comagmatic dunite–harzburgite–orthopyroxenite, with primitive levels of high-field-strength elements; (2) maximum values of Mg# in olivine (Ol, 93.3) and chromian spinel (Chr, 57.0) in the Dunite block (DB), which exceed those in Ol (91.7) and Chr (42.5) in the sills at Chapesvara, and (3) the presence of major contact-style chromite–IPGE-enriched zones hosted by the DB. A single batch of primitive, Al-undepleted komatiitic magma crystallized normally as dunite close to the outer contact, then toward the center. A similar magma gave rise to Chapesvara and other suites of the SB–TB megastructure. Crystallization proceeded from the early Ol + Chr cumulates to the later Ol–Opx and Opx cumulates with accessory Chr in the Orthopyroxenite zone. The accumulation of Chr resulted from efficient cooling along boundaries of the Dunite block. The inferred front of crystallization advanced along a path traced by vectors of Ol and Chr compositions. Grains and aggregates of Chr were mainly deposited early after the massive crystallization of olivine. Chromium, Al, Zn and H 2 O, all incompatible in Ol, accumulated to produce podiform segregations or veins of chromitites. This occurred episodically along the moving front of crystallization. Crystallization occurred rapidly owing to heat loss at the contact and to a shallow level of emplacement. The Chr layers are not continuous but rather heterogeneously distributed pods or veins of Chr–Ol–clinochlore segregations. Isolated portions of melt enriched in H 2 O and ore constituents accumulated during crystallization of Ol. Levels of f O 2 in the melt and, consequently, the content of ferric iron in Chr, increased progressively, as in other intrusions of the SB–TB megastructure. The komatiitic magma vesiculated intensely, which led to a progressive loss of H 2 and buildup in f ... Article in Journal/Newspaper Fennoscandian kola peninsula Tundra Directory of Open Access Journals: DOAJ Articles Kola Peninsula Pados ENVELOPE(29.800,29.800,68.101,68.101) Tulppio ENVELOPE(29.214,29.214,67.769,67.769) Minerals 11 1 68 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
chromite mineralization ultramafic complexes hypabyssal intrusions highly magnesian magma komatiites oxidation Mineralogy QE351-399.2 |
spellingShingle |
chromite mineralization ultramafic complexes hypabyssal intrusions highly magnesian magma komatiites oxidation Mineralogy QE351-399.2 Andrei Y. Barkov Andrey A. Nikiforov Larisa P. Barkova Vladimir N. Korolyuk Robert F. Martin Zones of PGE–Chromite Mineralization in Relation to Crystallization of the Pados-Tundra Ultramafic Complex, Serpentinite Belt, Kola Peninsula, Russia |
topic_facet |
chromite mineralization ultramafic complexes hypabyssal intrusions highly magnesian magma komatiites oxidation Mineralogy QE351-399.2 |
description |
The lopolithic Pados-Tundra layered complex, the largest member of the Serpentinite belt–Tulppio belt (SB–TB) megastructure in the Fennoscandian Shield, is characterized by (1) highly magnesian compositions of comagmatic dunite–harzburgite–orthopyroxenite, with primitive levels of high-field-strength elements; (2) maximum values of Mg# in olivine (Ol, 93.3) and chromian spinel (Chr, 57.0) in the Dunite block (DB), which exceed those in Ol (91.7) and Chr (42.5) in the sills at Chapesvara, and (3) the presence of major contact-style chromite–IPGE-enriched zones hosted by the DB. A single batch of primitive, Al-undepleted komatiitic magma crystallized normally as dunite close to the outer contact, then toward the center. A similar magma gave rise to Chapesvara and other suites of the SB–TB megastructure. Crystallization proceeded from the early Ol + Chr cumulates to the later Ol–Opx and Opx cumulates with accessory Chr in the Orthopyroxenite zone. The accumulation of Chr resulted from efficient cooling along boundaries of the Dunite block. The inferred front of crystallization advanced along a path traced by vectors of Ol and Chr compositions. Grains and aggregates of Chr were mainly deposited early after the massive crystallization of olivine. Chromium, Al, Zn and H 2 O, all incompatible in Ol, accumulated to produce podiform segregations or veins of chromitites. This occurred episodically along the moving front of crystallization. Crystallization occurred rapidly owing to heat loss at the contact and to a shallow level of emplacement. The Chr layers are not continuous but rather heterogeneously distributed pods or veins of Chr–Ol–clinochlore segregations. Isolated portions of melt enriched in H 2 O and ore constituents accumulated during crystallization of Ol. Levels of f O 2 in the melt and, consequently, the content of ferric iron in Chr, increased progressively, as in other intrusions of the SB–TB megastructure. The komatiitic magma vesiculated intensely, which led to a progressive loss of H 2 and buildup in f ... |
format |
Article in Journal/Newspaper |
author |
Andrei Y. Barkov Andrey A. Nikiforov Larisa P. Barkova Vladimir N. Korolyuk Robert F. Martin |
author_facet |
Andrei Y. Barkov Andrey A. Nikiforov Larisa P. Barkova Vladimir N. Korolyuk Robert F. Martin |
author_sort |
Andrei Y. Barkov |
title |
Zones of PGE–Chromite Mineralization in Relation to Crystallization of the Pados-Tundra Ultramafic Complex, Serpentinite Belt, Kola Peninsula, Russia |
title_short |
Zones of PGE–Chromite Mineralization in Relation to Crystallization of the Pados-Tundra Ultramafic Complex, Serpentinite Belt, Kola Peninsula, Russia |
title_full |
Zones of PGE–Chromite Mineralization in Relation to Crystallization of the Pados-Tundra Ultramafic Complex, Serpentinite Belt, Kola Peninsula, Russia |
title_fullStr |
Zones of PGE–Chromite Mineralization in Relation to Crystallization of the Pados-Tundra Ultramafic Complex, Serpentinite Belt, Kola Peninsula, Russia |
title_full_unstemmed |
Zones of PGE–Chromite Mineralization in Relation to Crystallization of the Pados-Tundra Ultramafic Complex, Serpentinite Belt, Kola Peninsula, Russia |
title_sort |
zones of pge–chromite mineralization in relation to crystallization of the pados-tundra ultramafic complex, serpentinite belt, kola peninsula, russia |
publisher |
MDPI AG |
publishDate |
2021 |
url |
https://doi.org/10.3390/min11010068 https://doaj.org/article/dfdc06c26cf34d7ebba4cf37fb3bd645 |
long_lat |
ENVELOPE(29.800,29.800,68.101,68.101) ENVELOPE(29.214,29.214,67.769,67.769) |
geographic |
Kola Peninsula Pados Tulppio |
geographic_facet |
Kola Peninsula Pados Tulppio |
genre |
Fennoscandian kola peninsula Tundra |
genre_facet |
Fennoscandian kola peninsula Tundra |
op_source |
Minerals, Vol 11, Iss 1, p 68 (2021) |
op_relation |
https://www.mdpi.com/2075-163X/11/1/68 https://doaj.org/toc/2075-163X doi:10.3390/min11010068 2075-163X https://doaj.org/article/dfdc06c26cf34d7ebba4cf37fb3bd645 |
op_doi |
https://doi.org/10.3390/min11010068 |
container_title |
Minerals |
container_volume |
11 |
container_issue |
1 |
container_start_page |
68 |
_version_ |
1787424469412741120 |