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We encourage to read the newest scientific monograph authored by Dr. Milosz Huber (Department of Geology, Soil Science and Geoinformation), published by the Maria Curie-Skłodowska University Press (link to offer). The subject of the presented geological research concerns the evolution of the platinum-bearing Paleoproterozoic layered moncheplutonic intrusion in northern Russia.
Huber M., 2021. Ewolucja kolsko-laplandzkiego pasa mobilnego na przykładzie platynonośnej paleoproterozoicznej intruzji warstwowanej moncheplutonu. Wydawnictwo UMCS, Lublin.
English summary:
Kola-Lapland Mobile Belt is located in Fennoscandia, cutting it from northwest to southeast. This structure was created as a result of the breakdown of the Kenorland supercontinent, in the Paleoproterozoic. There was then increased magmatism, which contributed to the formation of a series of layered, basic and ultra-basic rock intrusions with platinum group elements mineralization. One of such intrusions is the Monchepluton, located in the central part of the Kola-Lapland Mobile Belt. The age of this intrusion, estimated at 2.5 billion years, and its location prove the uniqueness of this unit, as it was created in the initial phase of the formation of the discussed mobile belt. The author presented the development of the Kola-Lapland Mobile Belt geology based on the mineralogical, petrographic, and geochemical characteristics of the Monchepluton and neighboring massifs. The characteristics of the Archean rocks around the Monchepluton and their influence on the intrusion are discussed. The layered, rhythmically overlapping nature of the peridotite and gabbroid rocks forming the Monchepluton was demonstrated. Events related to the formation and crystallization of Monchepluton are discussed. The influence of magma injection was demonstrated, and then the nature of the postmortem processes accompanying this intrusion was determined. The consecutive stages of metamorphism, tectonics, and vein formations related to the activity of the Kola-Lapland Mobile Belt were noted. The findings were based on the results of petrographic, mineralogical, and geochemical analyzes based on studies in the micro-area, the ratio of stable sulfur isotopes in sulfides, etc. The formation of oxide (Fe, Ti, Cr), sulfide (Ni, Fe, Cu), and platinum-bearing (Pt, Pd) with the indication of the individual phases, the range of their crystallization temperatures. The advantage of tellurides and bismuths over platinum and palladium arsenides was demonstrated, and many complex compounds of these elements were determined, which were formed as a result of hydrothermal processes in the rocks in question. These results were compared with similar intrusions occurring in the region (Monchetundra, Imandra, Fedoro-Pana, Lukkulajsvaara, Kolvitza) and the world (Stillwater, Bushveld, Sudbury), also based on own research results of these rocks. The formation of Monchepluton intrusion from primary magmas that have mantle characteristics involving supracrustal material was established. Next, the impact of the collision of the Belamoryian and Kola blocks on the nature of Monchepluton rocks was demonstrated. Examples of tectonic movements and dunes that contributed to the metasomatism of Monchepluton rocks were also described.
Further activity, estimated at over two billion years, of the Kola-Lapland Mobile Belt in later eras was demonstrated and these processes were mirrored in the rocks of Monchepluton. Finally, the processes of tectonic rejuvenation of the region and the action of the heat spot in the Palaeozoic, responsible for the production of several alkaline intrusions, such as Khibiny, Lovozero, Africanda, and their influence on the rocks of Monchepluton, are discussed. The demonstrated activity of various igneous and metamorphic processes was associated with the contraction and disintegration of such continents as Valbaara, Kenorland, Pangea, constituting an important, integral part of the development of the geological history of the Eastern European continent.
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