The Snezhnoe ruby deposit is located in the Muzkol–Rangkul anticlinorium within the Cimmerian zone of the Central Pamir. On the local scale, the deposit occurs on discrete relict bedding planes of calcitic marbles belonging to the Sarydzhilgin suite. Four ruby-bearing mineral assemblages are present within the main parts of the deposit: 1) scapolite + phlogopite + muscovite + margarite; 2) plagioclase + muscovite + margarite; 3) muscovite + phlogopite + margarite; 4) calcite. The ruby + calcite association is the most economically important, whereas the association of plagioclase + scapolite + phlogopite + muscovite is typical for the ruby-free parts of the deposit. Mica group minerals with a distinctive green color due to enhanced Cr and V concentrations are the main prospecting indicators for the ruby mineralization. The oxygen isotopic composition of the rubies is +15.3‰, a common value for crustal metamorphic and sedimentary rocks. The ratios of indicative trace elements in the rubies are Ga/Mg < 8.2, Fe/Mg < 51.2, Cr/Ga > 6.9 and Fe/Ti < 31.6. These values are characteristic for metamorphic corundum. The bulk ruby-bearing rocks have an initial ⁸⁷Sr/⁸⁶Sr ratio of ~0.70791 and εNd of ~−9.6, also pointing to the crustal origin of the deposit in agreement with the geological data. Ancient Al-enriched sediments are suggested to be a possible protolith for the ruby-bearing rocks. The temperature of the metamorphic processes was estimated at 760 ± 30 °C using Zr-in-rutile geothermometry. Raman mapping of rutile inclusions trapped within the ruby crystal indicates that the minimum pressure of mineralization was about one kilobar. The age determined by the Rb–Sr thermal ionization mass spectrometry of phlogopite, plagioclase and bulk rock is 23 ± 1.6 Ma, corresponding to the timing of relaxation after peak metamorphism during the Alpine–Himalayan Orogeny.

中文翻译：

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Snezhnoe红宝石矿床的成岩作用，中帕米尔

斯内兹诺（Snezhnoe）红宝石矿床位于帕米尔中部Cimmerian地区的Muzkol–Rangkul反气候层。在当地范围内，该沉积物发生在属于Sarydzhilgin套房的钙质大理石的离散遗迹铺床上。该矿床的主要部分中存在四种含红宝石的矿物组合：1）闪锌矿+金云母+白云母+玛格石；2）斜长石+白云母+玛格丽特; 3）白云母+金云母+玛格丽特; 4）方解石。红宝石+方解石的结合在经济上最重要，而斜长石+闪锌矿+金云母+白云母的结合是矿床中无红宝石的部分的典型特征。云母类矿物由于铬和钒的浓度增加而具有独特的绿色，是红宝石矿化的主要勘探指标。红宝石的氧同位素组成为+ 15.3‰，是地壳变质和沉积岩的共同值。红宝石中指示性微量元素的比率为Ga / Mg <8.2，Fe / Mg <51.2，Cr / Ga> 6.9和Fe / Ti <31.6。这些值是变质刚玉的特征。大块的含红宝石的岩石具有初始⁸⁷ Sr / ⁸⁶ Sr比为〜0.70791，εNd为〜-9.6，也表明该矿床的地壳成因与地质数据一致。古代富含铝的沉积物可能是含红宝石岩石的一种可能的原石。使用Zr-金红石型地热法估算了变质过程的温度为760±30°C。捕获在红宝石晶体中的金红石夹杂物的拉曼作图表明，最小矿化压力约为一千巴。由金云母，斜长石和块岩的Rb-Sr热电离质谱法确定的年龄为23±1.6 Ma，对应于高山-喜马拉雅造山运动中峰变质后的弛豫时间。