Behavior of selenium in silicic vein rocks and near granitic contacts

Selenium is very mobile in the conditions under which granitic rocks are crystallized and is depleted in silicic plutonic rocks and in pegmatites. It tends to separate from magma and be enriched into gaseous phase. The concentrations found in migmatized and fenitized rocks are much lower than the me...

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Bibliographic Details
Main Author: T. Koljonen
Format: Article
Language:English
Published: Geological Society of Finland 1974-12-01
Series:Bulletin of the Geological Society of Finland
Online Access:http://www.geologinenseura.fi/bulletin/Volume46/sgs_bt_046_2_pages_133_138.pdf
Description
Summary:Selenium is very mobile in the conditions under which granitic rocks are crystallized and is depleted in silicic plutonic rocks and in pegmatites. It tends to separate from magma and be enriched into gaseous phase. The concentrations found in migmatized and fenitized rocks are much lower than the mean in metamorphic rocks. Therefore selenium appears to migrate along fractures early in the metamorphic process and most of it before anatectic melts are formed. The selenium released from magma or by metamorphism from bedrock may later, with sulfur, form metasomatic ores and low temperature mineralizations, or it may appear at the surface in volcanic emanations and hot springs. Iron prevents to some extent the migration of selenium from magmatic melts and rocks.
ISSN:0367-5211
1799-4632