An undeformed Palaeoproterozoic granite pluton, located at Högberget, 10 km north of Kopparberg in western Bergslagen, has been investigated with respect to petrology, geochemistry, and geochronology. The geochemistry indicates a leucocratic and peraluminous granite and a REE pattern characterized by a large negative Eu-anomaly and a slight enrichment of the light REEs. Age determination by means of the U-Pb in zircon method yielded 1750+10 Ma. The Högberget granite is spatially and genetically related to the Wigström (Högfors) tungsten skam deposit and is comparable with other W-Mo related granites in western Bergslagen (e.g. Pingstaberg, Fjällberg, and Skålhöjden), which tradi-tionally are considered to have an anatectic origin. The data presented in this paper give further support to genetical models favouring a Late- to post-Svecofennian, granite-related origin for the W-Mo deposits in western Bergslagen and are in strong conflict with theories favouring a rift-related Early Svecofennian genesis for these ores. The recognition of c. 1.75 Ga Late Svecofennian granites in western Bergslagen indicates a large time interval between peak of regional • metamorphism and granite formation, which makes a genetic relation between regional metamorphism and the Late Svecofennian granites in western Bergslagen uncertain.
Original language | English |
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Pages (from-to) | 87-95 |
Number of pages | 9 |
Journal | GFF |
Volume | 117 |
Issue number | 2 |
DOIs | |
State | Published - Jun 1995 |
Externally published | Yes |
ID: 49688653