Geology, Mineralogy, Geochronology, And Sulfur Isotope Constraints On The Genesis Of The Luanling Gold Telluride Deposit, Western Henan Province, Central China

The Luanling gold telluride deposit in the Xiong'ershan region is located in the southern margin of the North China Craton. The deposit formed in four stages, that is, an early pyrite-quartz stage (I), a pyrite-molybdenite stage (II), a sulfide-telluride-gold stage (III), and a late carbonate stage (IV). Six species of telluride in stage (III) are recognized, including hessite, altaite, petzite, unidentified Au-Ag-Te mineral, empressite, and unidentified Ag-Te-S mineral. Gold occurs mostly as native gold and electrum along the microfractures of sulfides or the contact between sulfide and telluride. The mineralization temperature of stage I and stage III ranges from 296 to 377 degrees C and 241 to 324 degrees C, respectively. Tellurides in stage III precipitate at the log integral(S2) from -14.3 to -7.3 and log integral(Te2) from -17.4 to -9.4. The ores were formed in an oxidizing environment. The Re-Os model ages of molybdenite are 162-164 Ma, which indicate that the main ore formation stage was in the Late Jurassic. The Re contents of five molybdenite samples from the Luanling deposit have a range of 36.32-81.95 ppm, except for one large value of 220 ppm, which indicates that the ore-forming materials are mainly derived from a crustal-dominated source. The delta S-34 values of sulfides range from -17.6 to -6.2 parts per thousand, whereas those of sulfates are from 6.8 to 11.5 parts per thousand. The delta S-34( n-ary sumation S) value of the ore-forming system is 0.0-3.7 parts per thousand, indicating that the sulfur of the Luanling deposit derived from a deep igneous source. Mineral association and isotope data of the Luanling deposit, together with its geodynamic setting, imply that this deposit belongs to a part of the metallogenic system of the Nannihu-Sandaozhuang, Shangfangou porphyry molybdenum deposits, and the Late Jurassic granitic intrusions.