Uranium mineralization in response to regional metamorphism at Lilljuthatten, Sweden

Economic Geology
By:  and 

Links

Abstract

Analyses of six mineralized and five nonmineralized whole-rock drill core samples from the uranium deposit at Lilljuthatten yield a lead-lead isochron age of 420 + or - 1 m.y. This age corresponds to the last stage of the Caledonian Orogeny. None of the isotopic systems examined have completely retained the intrusive age of the Olden Granite, but data for several systems suggest an age of approximately 1,650 m.y. Indications that Caledonian hydrothermal activity strongly affected most of the Olden Granite. A model for the genesis of the ore deposit is proposed as follows: (1) derivation of a highly evolved granite by partial melting of crustal materials about 1,650 m.y. ago; (2) pervasive hydrothermal alteration and fracturing of the granite in response to the Caledonian Orogeny approximately 420 m.y. ago; (3) mobilization of uranium and lead in response to circulation of heated fluids; (4) precipitation of these elements in open fractures; and (5) recent modification of the Caledonian uranium distribution as a result of exposure to near-surface conditions.

Publication type Article
Publication Subtype Journal Article
Title Uranium mineralization in response to regional metamorphism at Lilljuthatten, Sweden
Series title Economic Geology
DOI 10.2113/gsecongeo.79.3.509
Volume 79
Issue 3
Year Published 1984
Language English
Publisher Society of Economic Geologists
Description 20 p.
First page 509
Last page 528
Google Analytic Metrics Metrics page
Additional publication details