Duration and timing of ore-bearing paleoproterozoic intrusions of kola province

摘要

The Kola Paleoproterozoic ore province is associated with layered ultramafic-mafic intrusions. The emplacement of these intrusions marks an important plume event in the gological history of the eastern Baltic Shield. The succession of the intrusions, which differ in metallogenic features, suggests that the plume remained active for about 100 MA (2505-2396) and the duration of formation of composite individual intrusions was 50+-20 Ma. U-Pb results for magmatic zircon and baddeleyite and some Sm-Nd and Rb-Sr data are presented.