Two episodic Au–Mo mineralization in the Laowan district from the Tongbai orogenic belt of China: Constraints from U–Pb dating of zircon, rutile, and REE phosphate, and Re–Os dating of molybdenite

Origin and mineralization significance of the ore-hosting Guishan Formation at the Laowan Gold Deposit in Qinling-Dabie Orogen, Central China

“…reported a 40 Ar/ 39 Ar age of 138±1 Ma obtained from muscovite. U-Pb dates of rutile and associated monazite from the auriferous altered rocks yielded ages of 120±2.0 Ma and 125.0±2.4 Ma, respectively (Yang et al, 2021). The difference of about 10 Ma between the two methods is within the range of analytical precision.…”

“…The above issues about the gold sources of lode Au deposits are also embodied in the Laowan gold deposit, which is one of the largest gold deposits in the Qinling-Dabie region (Fig. 1a) with the original gold reserves of more than 200 t. The Laowan gold deposit has long been regarded as a magmatic hydrothermal deposit, based on broad comparability of rutile and associated monazite U-Pb dating (120±2.0 Ma and 125.0±2.4 Ma, respectively; Yang et al, 2021), REE distribution patterns (Xie et al, 2005) of quartz from orebodies to those of the Laowan granite (132.5±2.4 Ma; zircon U-Pb dating, , together with magmatic derived sulfur isotope signatures of orerelated pyrites (Yang et al, 2015;Zhao et al, 2020). However, many studies demonstrated the ore-hosted Guishan Formation also provided part of ore-forming materials (e.g., Au, S, Pb), based on the whole-rock sulfur and lead isotopes similar to those of ores (Pan and Yue, 2002;Wan and Xu, 2005;Yang et al, 2015;Chen et al, 2017).…”

Two periods of magmatism in the Weishancheng ore concentration area, Henan Province: Evidences from zircon U‐Pb chronology, Hf isotopes and petrogeochemistry

“…The Tongbai area in Henan Province is located within the central eastern segment of the Qinling-Dabie collision Orogenic Belt (Figure 1a), situated between the Mesozoic-Cenozoic Fault basins of Nanyang and Wucheng. It serves as a significant concentration area for gold, silver, lead and zinc polymetallic deposits in China (Yang et al, 2021).…”

“…the Early Cretaceous granitic magma activity was robust and linked to large-scale metal deposit mineralization in the area (Mao et al, 2005(Mao et al, , 2010. For example, the diagenetic ages of the Laowan, Huashan and Heyu plutons range from 127 to 132 Ma (Yang et al, 2014(Yang et al, , 2021, all of which were products of the Yanshan magmatic activity. the error range.…”

“…The Tongbai area in Henan Province is located within the central eastern segment of the Qinling‐Dabie collision Orogenic Belt (Figure 1a), situated between the Mesozoic‐Cenozoic Fault basins of Nanyang and Wucheng. It serves as a significant concentration area for gold, silver, lead and zinc polymetallic deposits in China (Yang et al, 2021). The exposed strata in this region primarily consist of the Palaeoproterozoic Xiong'er Group, Palaeoproterozoic Qinling Group, Mesoproterozoic Kuanping Group, Mesoproterozoic Erlangping Group, Mesoproterozoic Guishanyan Formation and Nanwan Formation (Figure 1b).…”