Application of the Fractal Dimension Calculation Technique to Determine the Shape of Selected Monchepluton Intrusion Crystals (NE Fennoscandia)

Abstract

Thirty-eight samples of minerals from Paleoproterozoic Layered PGE Intrusion Monchepluton, located in NE Fennoscandia, were tested. An automated computational technique was used which involved counting the sides superimposed on vectorized graphics using separated crystal boundaries. The results were obtained for olivine, orthopyroxene, clinopyroxene, and plagioclase. On this basis, an interpretation of the mineral box fractal dimension was made, along with an interpretation of its nature in the rock in which it was found. The performed calculations were applied to the sampling positions, and maps of changes in fractal dimensions were prepared. The nature of the minerals studied was correlated with the type of rocks present in Monchepluton. Then, the fractal dimensions were scaled to a percentage scale determining the mean value for the euhedral crystal as 100%, and a map was obtained representing the advancement of secondary processes after summing these data for all four investigated minerals. This method was analyzed and its advantages and limitations shown.

Geoheritage of the Monchegorsk Igneous Layered Paleoproterozoic Intrusion (Kola Peninsula, Arctic Russia): Evaluation and Geotourism Opportunities

“…The discussed intrusion is built up with pyroxenites and labradorites and accompanied by rocks containing chromites and iron-nickel and copper sulfide ores. Recent studies have also shown the presence of PGE mineralization in them [37,39].…”

“…In the meridian wing there are massifs from the north: Traviannaya, Kumuzhia, Nittis (called NKT). In the latitudinal wing from the west: Sopcha, Nyud, Poaz and lying south of them: Vurechuayvench [35][36][37][38]. The intrusion is surrounded from the north by archaic rocks of the Kola series and from the east and south by the Proterozoic formations of the Imandra-Varzuga belt.…”

“…In the blocks belonging to the NKT, there are rocks of dunite and harzburgite, and clinopyroxenite rocks containing chromites (Figure 4A) and olivine-pyroxene bodies (Figure 4B). In the area of Sopcha, Nyud, and Poaz, there are orthopyroxenites, olivine norites and gabbronorites-also with numerous interesting zones showing the rhythm of the formation of intrusion [37,[50][51][52][53]. In the Hippik area, the gabbro is exposed [37,38].…”

“…In the area of Sopcha, Nyud, and Poaz, there are orthopyroxenites, olivine norites and gabbronorites-also with numerous interesting zones showing the rhythm of the formation of intrusion [37,[50][51][52][53]. In the Hippik area, the gabbro is exposed [37,38]. The whole intrusion is cut by numerous mineral veins of dolerites and prehnite-carbonate rocks and is also cemented with sulfides, sometimes taking massive forms, while in tectonic zones, there are breccias and mylonites [54][55][56].…”

“…Bornite and digenite are usually formed at the border of chalcopyrite and magnetite. In the vicinity of these minerals, they are enriched with tellurides and bismuths of platinum and palladium [37,39].…”