Rare Earth Elements in Middle Precambrian Volcanic Rocks of Finland, with a Discussion of the Origin of the Rocks
The contents of rare earth elements (REE) have been determined in five Svecofennian metamorphosed volcanic rocks and are compared with those found in the Karelian zone and Recent tholeiites. In the Svecofennian zone, REE contents in low silica volcanic rocks are like those in the calc-alkalic series...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
| Published: |
Geological Society of Finland
1975-12-01
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| Series: | Bulletin of the Geological Society of Finland |
| Online Access: | http://www.geologinenseura.fi/bulletin/Volume47/sgs_bt_047_pages_127_138.pdf |
| _version_ | 1819086667850448896 |
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| author | T. Koljonen R.J. Rosenberg |
| author_facet | T. Koljonen R.J. Rosenberg |
| author_sort | T. Koljonen |
| collection | DOAJ |
| description | The contents of rare earth elements (REE) have been determined in five Svecofennian metamorphosed volcanic rocks and are compared with those found in the Karelian zone and Recent tholeiites. In the Svecofennian zone, REE contents in low silica volcanic rocks are like those in the calc-alkalic series and in continental tholeiites, whereas in the Karelian zone they are like those in island arc tholeiites. It is argued that in the Karelian zone, where magmatism initiated, tholeiitic basalts originated in the upper mantle; as shown in normalized form, the light REE are depleted, reflecting the distribution pattern found, for example, in rocks of pyrrolite composition. As orogeny advanced, more and more crustal material — basement and geosynclinal sediments — was recycled and the REE distribution pattern changed to that found in the synorogenic calc – alkalic rocks (1.8–1.95 Ga), reflecting the REE pattern present in sediments. The chemical composition of the magmatic rock series formed during Svecokarelian folding is quite like that observed in island arc systems. |
| first_indexed | 2024-12-21T21:23:54Z |
| format | Article |
| id | doaj.art-b429c086c76d4967bae407b944f324b3 |
| institution | Directory Open Access Journal |
| issn | 0367-5211 1799-4632 |
| language | English |
| last_indexed | 2024-12-21T21:23:54Z |
| publishDate | 1975-12-01 |
| publisher | Geological Society of Finland |
| record_format | Article |
| series | Bulletin of the Geological Society of Finland |
| spelling | doaj.art-b429c086c76d4967bae407b944f324b32022-12-21T18:49:48ZengGeological Society of FinlandBulletin of the Geological Society of Finland0367-52111799-46321975-12-01471-212713810.17741/bgsf/47.1-2.015Rare Earth Elements in Middle Precambrian Volcanic Rocks of Finland, with a Discussion of the Origin of the RocksT. KoljonenR.J. RosenbergThe contents of rare earth elements (REE) have been determined in five Svecofennian metamorphosed volcanic rocks and are compared with those found in the Karelian zone and Recent tholeiites. In the Svecofennian zone, REE contents in low silica volcanic rocks are like those in the calc-alkalic series and in continental tholeiites, whereas in the Karelian zone they are like those in island arc tholeiites. It is argued that in the Karelian zone, where magmatism initiated, tholeiitic basalts originated in the upper mantle; as shown in normalized form, the light REE are depleted, reflecting the distribution pattern found, for example, in rocks of pyrrolite composition. As orogeny advanced, more and more crustal material — basement and geosynclinal sediments — was recycled and the REE distribution pattern changed to that found in the synorogenic calc – alkalic rocks (1.8–1.95 Ga), reflecting the REE pattern present in sediments. The chemical composition of the magmatic rock series formed during Svecokarelian folding is quite like that observed in island arc systems.http://www.geologinenseura.fi/bulletin/Volume47/sgs_bt_047_pages_127_138.pdf |
| spellingShingle | T. Koljonen R.J. Rosenberg Rare Earth Elements in Middle Precambrian Volcanic Rocks of Finland, with a Discussion of the Origin of the Rocks Bulletin of the Geological Society of Finland |
| title | Rare Earth Elements in Middle Precambrian Volcanic Rocks of Finland, with a Discussion of the Origin of the Rocks |
| title_full | Rare Earth Elements in Middle Precambrian Volcanic Rocks of Finland, with a Discussion of the Origin of the Rocks |
| title_fullStr | Rare Earth Elements in Middle Precambrian Volcanic Rocks of Finland, with a Discussion of the Origin of the Rocks |
| title_full_unstemmed | Rare Earth Elements in Middle Precambrian Volcanic Rocks of Finland, with a Discussion of the Origin of the Rocks |
| title_short | Rare Earth Elements in Middle Precambrian Volcanic Rocks of Finland, with a Discussion of the Origin of the Rocks |
| title_sort | rare earth elements in middle precambrian volcanic rocks of finland with a discussion of the origin of the rocks |
| url | http://www.geologinenseura.fi/bulletin/Volume47/sgs_bt_047_pages_127_138.pdf |
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