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Vol. 5 (2002 year), No. 1
Gavrilenko B.V., Nikitin I.V., Zozulya D.R., Kudryashov N.M., Petrovsky M.N., Korsakova O.P. and Galkin N.N.
Geology, tectonics, age and metallogeny of the Archaean Kolmozero-Voron'ya suture zone, the Kola region
The new data on geology, structure and the age of the Archaean Kolmozero-Voron'ya suture zone from the NE Baltic Shield have been presented. The zone is located in the junction of Murmansk, Central Kola and Keivy terranes and marks the ancient Titovka-Keivy deep-seated fault. It is characterized by the tectonics suture style and was formed in the conditions of the sliping plastic and quasi-plastic flow. The structural combination of the steep longitudinal slips with cross reverse faults and trusts, separated by the lenses' and slices' assemblages, was formed under the dominating compression combined with the compensating extension. There are several stages in the suture zone evolution: protooceanic with komatiite-toleite magmatism (3.0-2.9 Ga); volcanic arc with andesite-rhyolite magmatism (2.9-2.8 Ga); regional metamorphism and granitization (2.7-2.6 Ga); regressive metamorphism and potassium metasomatosis (2.5-2.2 Ga). The metallogenic evolution of the Kolmozero-Voron'ya zone was the following: siderophile elements - Fe, Ni, Au, Ag (mantle source), chalkophile elements - Cu, Mo, Pb, Bi (mixed mantle-crustal source), lithophile elements - Li, Cs, Be, Ta, Nb (crustal source), and it is in accordance with the change of the tectonic regimes in the zone geological history.
(in Russian, стр.18, fig. 7, tables. 2, ref 84, MS Word 95, MS Word 95 1670 Kb)
Vol. 5 (2002 year), No. 1
Korsakova O.P.
The weathering crust in the Sopchyavr lake depression and possible formation of the precious metal placers
The paper has considered the geological, geomorphological, lithological, mineralogical and geochemical data characterized the dislocated crust of weathering discovered during the prospect drilling of the Sopchyavr lake depression. The age of the weathering crust is not younger than the Miocene-Pliocene. It has been established that weathering conditions were appropriate to produce hypergene minerals, to release mineral phases bearing precious metals and subsequent possible formation of the placers. The rocks of the crust contain some concentration of chromium, nickel, platinum, palladium and gold.
(in Russian, стр.6, fig. 4, tables. 0, ref 9, MS Word 95, MS Word 95 249 Kb)
Vol. 12 (2009 year), No. 3
Korsakova O.P., Kolka V.V., Savchenko S.N.
Block structures of the Kola Peninsula, their resistance under the conditions of natural and technical systems (by the example of the Khibiny and Lovozero Mountains)
The paper presents the results of comprehensive geological and petrographic, isotope geochemical (U-Pb, Sm-Nd, REE) and geochemical exploring investigations of the Monchetundra intrusion rocks. The studied cumulative stratigraphy for the intrusive rocks forms the basis for the division of the vertical rock sequence into three zones. The lower zone is dominated with orthopyroxene and olivine cumulates. The middle zone consists of pyroxene-plagioclase and plagioclase cumulates. And the upper one is mainly composed of plagioclase cumulates. The internal structure of the intrusion displays the lateral increase in differentiation degree from the eastern flank southwards (for the lower zone) and westwards (for the middle and upper zones). A new manifestation of noble metal stratiform mineralization has been found. It is confined to the horizon of the trachitoid gabbronorite (the middle zone). The mineralization locates in the western part of the intrusion that readily agrees with internal structure. The U-Pb dating has allowed revealing two intrusive phases for the rocks of the upper part: an earlier, 2.47 Ga, and an older, 2.45 Ga, one. The initial magma for the rocks of the middle and upper zones has been found to differ. The initial magma for the rocks of the lower zone of the Monchetundra intrusion was slightly enriched both with light and heavy rare earth elements. The rocks of the middle and upper zones were formed of the primary melts that were close in composition being slightly enriched with LREE. The differences in the REE fractionation have been shown for the different zones of the intrusion, including the initial magma close in composition that yielded the rocks of the middle and upper zones of the intrusion in the course of differentiation and crystallization. Thus, the REE fractionation coefficient, (La/Yb)N directly correlates with the content of Al2O3, CaO, total and particular iron content in the rocks of the upper zone, that is not characteristic of the middle zone rocks. It has been concluded that the collected data on REE, and U-Pb and Sm-Nd isotopy assume the formation of the Monchetundra intrusion as a result of subsequent emplacement, differentiation, and crystallization of the melts from the single anomalous source with possible minor contribution from the depleted source.
(in Russian, стр.14, fig. 9, tables. 0, ref 18, Adobe PDF, Adobe PDF 0 Kb)
Vol. 15 (2012 year), No. 2
Kolka V.V., Korsakova O.P.
Application of geological methods for dating of stone labyrinths on the White Sea coast
The geological and geomorphological methods of the investigation of the relative sea level changes during the Late Holocene jointly with traditional methods of archeology have been used for determining age of the archaeological monuments – the stone labyrinths known on the Kandalaksha coast of the White Sea.
(in English, стр.8, fig. 7, tables. 1, ref 17, Adobe PDF, Adobe PDF 0 Kb)