Re-Os Geochronology and Sulfur Isotopes of the Lyangar W-Mo Deposit: Implications for Permian Tectonic Setting in South Tianshan Orogen, Uzbekistan.

The Lyangar W-Mo skarn deposit is located in the Nuratau area (western Uzbekistan), South Tianshan Orogen. The skarn system is distributed along the contact zone between the Aktau granitoid and the upper Paleozoic sedimentary rocks. Six molybdenite samples from the Lyangar deposit yielded a Middle Permian Re-Os isochron age of 268.0 ± 12.0 Ma (MSWD = 0.43) and a weighted mean age of 263.8 ± 1.5 Ma (MSWD = 0.22). Molybdenites have low Re contents (12.49 to 16.65 ppm), indicative of a continental crust-dominated source. The molybdenite δ³⁴S values fall inside a narrow range (1.0 to 3.8‰; average 2.3‰), implying that the ore metals were likely derived from the granite intrusion. We concluded that the Lyangar W-Mo deposit was formed in a post-collisional setting caused by continental collision between the Tarim and Kazakhstan cratons. [ABSTRACT FROM AUTHOR]