Painting the volcanic landscape of early Fennoscandia : Geochronology of the Meso- and Neoarchaean Suomussalmi-Kuhmo-Tipasjärvi greenstone complex, Karelia Province, Finland
Archaean cratons contain the oldest parts of the Earth s crust that have survived crustal recycling processes. Archaean greenstone belts are vital parts of these cratons and preserve the oldest volcanoclastic and sedimentary rocks on Earth. They play an important part in the study of the evolution o...
Main Author: | |
---|---|
Other Authors: | , , , , , , |
Format: | Doctoral or Postdoctoral Thesis |
Language: | English |
Published: |
Helsingin yliopisto
2016
|
Subjects: | |
Online Access: | http://hdl.handle.net/10138/163081 |
id |
ftunivhelsihelda:oai:helda.helsinki.fi:10138/163081 |
---|---|
record_format |
openpolar |
spelling |
ftunivhelsihelda:oai:helda.helsinki.fi:10138/163081 2023-08-20T04:06:26+02:00 Painting the volcanic landscape of early Fennoscandia : Geochronology of the Meso- and Neoarchaean Suomussalmi-Kuhmo-Tipasjärvi greenstone complex, Karelia Province, Finland Lehtonen, Elina Bleeker, Wouter University of Helsinki, Faculty of Science, Department of Geosciences and Geography Luonnontieteellinen keskusmuseo Helsingin yliopisto, matemaattis-luonnontieteellinen tiedekunta, geotieteiden ja maantieteen laitos Helsingfors universitet, matematisk-naturvetenskapliga fakulteten, institutionen för geovetenskaper och geografi Hölttä, Pentti Halla, Jaana 2016-05-31T13:21:22Z application/pdf http://hdl.handle.net/10138/163081 eng eng Helsingin yliopisto Helsingfors universitet University of Helsinki URN:ISBN:978-951-51-1351-1 http://hdl.handle.net/10138/163081 URN:ISBN:978-951-51-1352-8 Julkaisu on tekijänoikeussäännösten alainen. Teosta voi lukea ja tulostaa henkilökohtaista käyttöä varten. Käyttö kaupallisiin tarkoituksiin on kielletty. This publication is copyrighted. You may download, display and print it for Your own personal use. Commercial use is prohibited. Publikationen är skyddad av upphovsrätten. Den får läsas och skrivas ut för personligt bruk. Användning i kommersiellt syfte är förbjuden. geologia Text Doctoral dissertation (article-based) Artikkeliväitöskirja Artikelavhandling doctoralThesis 2016 ftunivhelsihelda 2023-07-28T06:32:22Z Archaean cratons contain the oldest parts of the Earth s crust that have survived crustal recycling processes. Archaean greenstone belts are vital parts of these cratons and preserve the oldest volcanoclastic and sedimentary rocks on Earth. They play an important part in the study of the evolution of the early Earth and formation of stable continental crust. One of the most important questions related to Archaean greenstone belts is how they were initially formed. Various tectonic processes have been suggested and the pertinent geological environments remain open for scientific debate. Absolute age determinations of plutonic and supracrustal rocks provide an essential tool for understanding crustal evolution of the early Earth. This thesis focuses on the largest Archae¬an greenstone association in eastern Finland: the Suomussalmi-Kuhmo-Tipasjärvi complex, which belongs to the Karelia Province of the Fennoscandian shield. The main objective of the thesis is to constrain a detailed geochronology for the felsic and intermediate volcanic rocks, as well as sedimentary rocks of the greenstone complex, and associated plutonic rocks. The ages of the selected samples were determined with second¬ary ion mass spectrometry (SIMS) and laser-ab¬lation multi-collector inductively-coupled-mass-spectrometry (LA-MC-ICPMS), and whole-rock samples were analyzed for their major and trace element compositions. The felsic and intermediate volcanic rocks of the Suomussalmi-Kuhmo-Tipasjärvi green¬stone complex can be divided into four distinct age groups based on pre-existing and new geochronological data: 2.94 Ga, 2.84 Ga, 2.82 Ga, and 2.80 2.79 Ga. The Suomussalmi greenstone belt contains the oldest volcanic phase (2.94 Ga), and the Tipasjärvi and Kuhmo greenstone belts the youngest volcanic phase (2.80 2.79 Ga). The new age determinations validate a chronostrati¬graphic interpretation for each belt. The updated chronostratigraphic model of the Suomussalmi greenstone belt comprises four volcanic units: ca. 2.94 Ga (Luoma unit), 2.87 ... Doctoral or Postdoctoral Thesis Fennoscandia Fennoscandian karelia* Helsingfors Universitet: HELDA – Helsingin yliopiston digitaalinen arkisto |
institution |
Open Polar |
collection |
Helsingfors Universitet: HELDA – Helsingin yliopiston digitaalinen arkisto |
op_collection_id |
ftunivhelsihelda |
language |
English |
topic |
geologia |
spellingShingle |
geologia Lehtonen, Elina Painting the volcanic landscape of early Fennoscandia : Geochronology of the Meso- and Neoarchaean Suomussalmi-Kuhmo-Tipasjärvi greenstone complex, Karelia Province, Finland |
topic_facet |
geologia |
description |
Archaean cratons contain the oldest parts of the Earth s crust that have survived crustal recycling processes. Archaean greenstone belts are vital parts of these cratons and preserve the oldest volcanoclastic and sedimentary rocks on Earth. They play an important part in the study of the evolution of the early Earth and formation of stable continental crust. One of the most important questions related to Archaean greenstone belts is how they were initially formed. Various tectonic processes have been suggested and the pertinent geological environments remain open for scientific debate. Absolute age determinations of plutonic and supracrustal rocks provide an essential tool for understanding crustal evolution of the early Earth. This thesis focuses on the largest Archae¬an greenstone association in eastern Finland: the Suomussalmi-Kuhmo-Tipasjärvi complex, which belongs to the Karelia Province of the Fennoscandian shield. The main objective of the thesis is to constrain a detailed geochronology for the felsic and intermediate volcanic rocks, as well as sedimentary rocks of the greenstone complex, and associated plutonic rocks. The ages of the selected samples were determined with second¬ary ion mass spectrometry (SIMS) and laser-ab¬lation multi-collector inductively-coupled-mass-spectrometry (LA-MC-ICPMS), and whole-rock samples were analyzed for their major and trace element compositions. The felsic and intermediate volcanic rocks of the Suomussalmi-Kuhmo-Tipasjärvi green¬stone complex can be divided into four distinct age groups based on pre-existing and new geochronological data: 2.94 Ga, 2.84 Ga, 2.82 Ga, and 2.80 2.79 Ga. The Suomussalmi greenstone belt contains the oldest volcanic phase (2.94 Ga), and the Tipasjärvi and Kuhmo greenstone belts the youngest volcanic phase (2.80 2.79 Ga). The new age determinations validate a chronostrati¬graphic interpretation for each belt. The updated chronostratigraphic model of the Suomussalmi greenstone belt comprises four volcanic units: ca. 2.94 Ga (Luoma unit), 2.87 ... |
author2 |
Bleeker, Wouter University of Helsinki, Faculty of Science, Department of Geosciences and Geography Luonnontieteellinen keskusmuseo Helsingin yliopisto, matemaattis-luonnontieteellinen tiedekunta, geotieteiden ja maantieteen laitos Helsingfors universitet, matematisk-naturvetenskapliga fakulteten, institutionen för geovetenskaper och geografi Hölttä, Pentti Halla, Jaana |
format |
Doctoral or Postdoctoral Thesis |
author |
Lehtonen, Elina |
author_facet |
Lehtonen, Elina |
author_sort |
Lehtonen, Elina |
title |
Painting the volcanic landscape of early Fennoscandia : Geochronology of the Meso- and Neoarchaean Suomussalmi-Kuhmo-Tipasjärvi greenstone complex, Karelia Province, Finland |
title_short |
Painting the volcanic landscape of early Fennoscandia : Geochronology of the Meso- and Neoarchaean Suomussalmi-Kuhmo-Tipasjärvi greenstone complex, Karelia Province, Finland |
title_full |
Painting the volcanic landscape of early Fennoscandia : Geochronology of the Meso- and Neoarchaean Suomussalmi-Kuhmo-Tipasjärvi greenstone complex, Karelia Province, Finland |
title_fullStr |
Painting the volcanic landscape of early Fennoscandia : Geochronology of the Meso- and Neoarchaean Suomussalmi-Kuhmo-Tipasjärvi greenstone complex, Karelia Province, Finland |
title_full_unstemmed |
Painting the volcanic landscape of early Fennoscandia : Geochronology of the Meso- and Neoarchaean Suomussalmi-Kuhmo-Tipasjärvi greenstone complex, Karelia Province, Finland |
title_sort |
painting the volcanic landscape of early fennoscandia : geochronology of the meso- and neoarchaean suomussalmi-kuhmo-tipasjärvi greenstone complex, karelia province, finland |
publisher |
Helsingin yliopisto |
publishDate |
2016 |
url |
http://hdl.handle.net/10138/163081 |
genre |
Fennoscandia Fennoscandian karelia* |
genre_facet |
Fennoscandia Fennoscandian karelia* |
op_relation |
URN:ISBN:978-951-51-1351-1 http://hdl.handle.net/10138/163081 URN:ISBN:978-951-51-1352-8 |
op_rights |
Julkaisu on tekijänoikeussäännösten alainen. Teosta voi lukea ja tulostaa henkilökohtaista käyttöä varten. Käyttö kaupallisiin tarkoituksiin on kielletty. This publication is copyrighted. You may download, display and print it for Your own personal use. Commercial use is prohibited. Publikationen är skyddad av upphovsrätten. Den får läsas och skrivas ut för personligt bruk. Användning i kommersiellt syfte är förbjuden. |
_version_ |
1774717484311511040 |