Origin and nature of the mineralizing fluids of thrust zone fluorites in Celikhan (Adiyaman, Eastern Turkey): A geochemical approach

Abstract

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.

Variation of mineralizing fluids and fractionation of REE during the emplacement of the vein-type fluorite deposit at Bozijan, Markazi Province, Iran

“…Moreover, the similarity between the overall trends of chondrite-normalized REE patterns for fluorites and host rocks (Fig. 10) may mean that the host rocks are the source of REE (Schwinn and Markl, 2005) and, possibly, F. The lower mobility of REE relative to F during leaching from the host rocks by percolating solutions probably caused the lower ∑REE content of the hydrothermal fluid and then of fluorites with respect to the slates (Sasmaz et al, 2005a). 11.…”

“…However, since calcite is much less abundant than fluorite in Bozijan, considering that it has an important effect on the REE pattern of fluorite seems irrelevant. Fluorites with low ∑REE contents are described as those that have been derived from a sedimentary environment (Hill et al, 2000;Ronchi et al, 1993;Sasmaz et al, 2005a). This interpretation can also be true for Bozijan fluorites, as the host rocks of the veins are either sedimentary rocks or slightly metamorphosed sedimentary rocks.…”

“…Geochemistry of rare earth elements (REEs) has been widely used by numerous researchers to understand the geologic conditions under which fluorite is deposited (e.g., Castorina et al, 2008;Sallet et al, 2005;Sánchez et al, 2010;Sasmaz et al, 2005a;Xiang et al, 2010). Moreover, many researchers (Constantopoulos, 1988;Hein et al, 1990;ƠConnor et al, 1993;Palmer and Williams-Jones, 1996;Sasmaz and Yavuz, 2007;Strong et al, 1984;Williams-Jones et al, 2000) combined geochemical data with fluid inclusion studies to unravel fluorite genesis.…”

Trace and Rare Earth Elements, and Sr Isotopic Compositions of Fluorite from the Shihuiyao Rare Metal Deposit, Inner Mongolia: Implication for Its Origin

“…Fluorite and its trace element geochemical features have been studied by many researchers in an attempt to understand the geological conditions that occurred during the formation of fluorite and associated mineralization [1][2][3][4][5][6][7][8][9]. Fluorite is one of the most common hydrothermal minerals in many deposits, which has relatively high rare earth element (REE) contents.…”

“…Fluorite is one of the most common hydrothermal minerals in many deposits, which has relatively high rare earth element (REE) contents. Therefore, the REE concentrations of fluorite occurring in different stages can provide insights into the element behavior and the evolution of a hydrothermal fluid [1][2][3]5,7,8,10,11]. In addition, because Rb is much less compatible than Sr in fluorite, fluorite will possess a very low Rb/Sr ratio, permitting the determination of 87 Sr/ 86 Sr ratio of fluids from which fluorite precipitated [10,[12][13][14][15].…”