Figure 1. Early Paleoproterozoic Baltic Large Igneous
Province of the siliceous high-Mg (boninite-like) series.
(1) Svecofennides (Late Paleoproterozoic); (2) Paleoproterozoic
volcanosedimentary belts with SHMS rocks at the base; (3) Early
Paleoproterozoic transitional mobile belts: BMB - Belomorian
Mobile Belt, TLB - Tersk-Lotta Belt; (4) Early Paleoproterozoic
Lapland-Umba Granulite Belt (LUGB) with Porieguba-Umba block
(PUB); (5) Archean basement of the Baltic Province; (6) largest
layered intrusions: (B) Burakovka, (Kem) Kemi, (K) Koitilainen,
(O) Olanga (Oulanka) group, (Pe) Penikat, (To) Tornio,
(G) Generalskaya Mount, (Ko) Koilismaa, (Mo) Monchegorsk Complex,
(Pa) Pana Tundra, (F) Fedorov Tundra, (Po) Portimo, (7) Late
Paleoproterozoic Main Lapland Thrust, (8) suture zone of
Caledonian nappes.
The upper inset map shows the reconstruction of the
location of the main tectonic features in the Early
Paleoproterozoic, the lower inset map is the schematic
geological map of a typical area in the Belomorian Belt with
small bodies of basic and ultrabasic rocks of the drusite complex (Northern Karelia,
Pezhostrov I., Keretsky Archipelago, the White Sea): (1) small
lenticular boudins of garnet amphibolite; (2) thick-layered
bodies of plagioclase lherzolite and olivine gabbronorite with
disrupted contacts; (3) indistinctly layered metamorphozed
gabbronorite bodies; (4) metagabbro-anorthosite bodies:
(a) coarse-grained rocks, (b) fine- and medium-grained rocks in
inner contacts; (5) Archean plagiomigmatites.