EVOLUTION OF FLUID PHASE IN A SINGLE MIAROLITIC CAVITY OF GRANITIC PEGMATITE ON THE BASIS OF QUARTZ-HOSTED FLUID INCLUSION STUDY (VERHNESHIBANOVSKY DEPOSIT, PRIMORYE, RUSSIA)

摘要

The obtained results demonstrate that thernhydrothermal medium of the miarolitic cavity wasrnheterogeneous at the early stages and becomernhomogeneous at the end of the quartzrncrystallization. Early fragments were formed fromrnmedium consisted of relatively diluted liquidrnaqueous fluid and brine. Salinity of the both fluidsrndecreased with decreasing temperature. Earlyrnaqueous fluids were rich in Pb, Zn, Fe, Mn, Ca, As,rnand Sb, which were dissolved in form of chloriderncompounds with minor carbonates, sulfates, and,rnprobably, borates. Intermediate fragment werernformed from the fluids with simpler compositions.rnThese fluids where composed mostly of Na-Krnchloride aqueous solutions with minor Fe and Mn.rnThe latest zones were formed fromrnhomogeneous K-Na chloride solutions. Therntransition from high-concentrated heterogeneousrnmedium to diluted homogeneous one occurs at thernlevel of the fragment 3. It was accompanied byrndramatic change in chemical and phaserncomposition of the miarolitic fluids and manifestedrnthrough the change of color of quartz. Our studyrnprovides an example of evolution of the aqueousrnfluid, which segregated from pegmatite magma andrnparticipated in the formation of postmagmaticrnmineralization. The data obtained will be used torndevelop a model of postmagmatic mineralizationrnfrom the magmatic aqueous fluid.rnThe study was carried out with the financialrnsupport of Russian Fund for Basic Research (grantrnN 13_05_90728_mol_rf_nr).