Fluorite and fluorite-bearing Pb-Zn-Ag (Cu) deposits are quite common in granitoids and associated skarn formations that are products of Late Cretaceous -Early Paleocene magmatic intrusions into Paleozoic metamorphic rocks of the so called Central Anatolian massif. This study investigates the geochemical features, mainly REE distributions, of fluorites from the Akdagmadeni fluorite and fluorite bearing PbZn -Ag (Cu) deposits. These include the vein type Tad Dere, epidote-skarn hosted Büyükçal Tepe and the skarn and granite hosted Akçakisla deposits. The REE contents of these deposits are 20.6 -48.5 ðx ¼ 36:0Þ, 61.3 -149.3 ðx ¼ 113:0Þ and 279.2-4222.4 ðx ¼ 1280:0Þ ppm for the Tad D., Büyükçal T. and Akçakisla, respectively.In general, the REE contents are intermediate to high and decrease in abundance with increasing distance from the granitic bodies. The LREE contents are dominantly higher than HREE contents and REE normalized patterns indicate decreasing abundances with increasing atomic number. These indicate that all the fluorites are early stage mineralizations. However, Tb/Ca -Tb/La ratios show distinct differences in the nature of the mineralizing fluids. The high ratios of Akçakisla fluorites are evidence of mineralizing fluids rich in late-stage differentiates from a felsic magma, while intermediate to high ratios of the Büyükçal T. fluorites are products of late-stage differentiates from hydrothermal fluids. Tad D. fluorites were mineralized under hydrothermal conditions. Decreasing SREE contents in the order of Akçakisla, Büyükçal T., and Tad D., and Sc/Eu vs Sr distribution (Sr increases with increasing distance from the magmatic rocks) also supports this order of formation. Each of the three types of fluorite deposits plot in well-defined areas in the Sc/Eu vs Sr diagram. Eu and Ce anomalies give a mixed pattern; the Tad D. fluorites have strong negative Eu anomalies indicating low T and low f o 2 mineralizing fluids. Strong positive Eu anomalies for the Akçakisla fluorites are probably due to high f o 2 : The Ce anomalies are strongly negative for the Akçakisla, negative for the Büyükçal T. and weakly negative for the Tad D. fluorites. These indicate high f o 2 conditions for the Akçakisla, intermediate for the Büyükçal T. and low for the Tad D. fluorites. Because of distinguishable differences in REE patterns, the fluorite deposits plot in well-defined areas in Sc/Eu vs Sr, (La/Yb) n -(Eu/Eu p ) n , Sr -(Eu/Eu p ) n , Sc-SREE, (Tb/Yb) n -(La/Yb) n , Tb/Ca -Tb/La diagrams, and indicate different origins and depositional histories.The homogenization temperatures ðT H Þ range from 156 to 185 8C with the corresponding salinities between 12 and 23 wt% NaCl for the Tad Dere ores, 390 to 430 8C with the corresponding salinities 8 and 12 wt% NaCl for the Akçakisla and Büyükçal Tere ores.Consequently, the field, fluid inclusion data and REE geochemistry indicate that the composition of mineralizing fluids, the locations of ore formations relative to the plutons, the mineralizing mechanisms and the prevailing...
The Çelikhan fluorite mineralization is concentrated in the thrust zone between the Pinarbasi Formation, which forms the hanging wall, and the Kalecik Limestone foot wall. Fluorite occurs as fracture fills in the thrust zone and as replacement of the foot wall. The wall rock alteration consists of calcite, barite, quartz and kaolinite. The total REE contents of the country rocks, especially the mica-and calc-schists of the Pinarbasi formation at 519 ppm, are higher than those of fluorites. The chondrite normalized REE patterns of country rock and fluorites display generally identical trends. However, fluorite patterns show positive Eu and negative Ce anomaly indicative of low temperature and high fo 2 conditions. Cross plots of the Tb/Ca-Tb/La, (La/Yb) n-(Tb/Yb) n and (La/Yb) n (Eu/Eu*) n ratios of the fluorites indicate deposition by low temperature hydrothermal waters. The REE and F were probably leached from the Pinarbasi Formation by the mineralizing solutions. The mineralizing fluids are probably meteoric and formation waters heated at depth along the thrust zone by the natural thermal gradient and/or formation waters heated and mobilized by thrusting.
The studied Pb-Zn and Cu veins occur as N-S trending and vertically dipping features in quartz diorite of Coniacian -Campanian Elazig Magmatic Complex. The complex has characteristics typical of arc magmatism and is composed of granitoids and, volcanic, subvolcanic and pyroclastic rocks.The veins are 0.5-2.5 m. thick and their lengths reach up to 750 m. The ore of veins are either massive or disseminated in gangue of carbonate minerals, quartz and barite. The veins display two sets of mineral assemblages: (1) Pb-Zn veins are composed of galena, freibergite, barite, sphalerite, chalcopyrite, pyrite, a Pb-Cl phase and native silver; (2) Cu veins have a mineral association of chalcopyrite, pyrite, galena, sphalerite, cubanite, bismuthinite and fahlore. The ore bodies are accompanied by narrow but intensely developed wall rock alterations of argillization, carbonatization and silicification.Chemical analyses of ore samples indicate high Pb, Ag, Sb, Zn, Ba and Cu contents in the veins and high correlation values between Pb-Ag, Pb-Ba, Pb-Zn, Sb-Ag, Cd-Sb and Ba -Cd.The REE geochemistry points to ore deposition under acidic conditions and probably as a product of the final stages of magmatism. Field, microscopic and geochemical data also indicate that the ores are related to the last phases of the magmatic activity of the Elazig Magmatic Complex.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.