Geology and geochronology of the Lalingzaohuo cobalt-bearing copper polymetallic skarn deposit, East Kunlun

作者：Jiahao Chen, Huaying Wu, Xianglong Niu, Sida Niu, Yingchao Wang, Jinhong Wang, Zhi-an Wang · 发表于：Ore Geology Reviews · 年份：2023 · DOI：10.1016/j.oregeorev.2023.105349 · 被引用次数：16 · 研究领域：Geological and Geochemical Analysis、Geochemistry and Geologic Mapping、earthquake and tectonic studies

The Lalingzaohuo cobalt-bearing Cu polymetallic skarn deposit, located in the central part of the East Kunlun Orogenic Belt, is mainly hosted in the Paleoproterozoic Jinshuikou Group. The occurrence and genesis of cobalt at Lalingzaohuo were investigated by field geology, mineralogy, geochronology, and electron probe microanalyses (EPMA), that these data provide some insights into the ore-forming process and also show the key characteristics of a cobalt-bearing skarn. Garnet U-Pb dating yielded a lower intercept 206Pb/238U date of 207.5 ± 4.9 Ma, younger than spatially related quartz diorite (SHRIMP zircon U–Pb dating, 246.8 ± 1.7 Ma), which suggested that the Lalingzaohuo was formed during the Late Triassic. Photomicrographs and EPMA data confirm that Co mineralization is associated with metal sulfides, which develop at the sulfide stage. Cobalt occurrence in Lalingzaohuo is restricted to Co mineral (cobaltite) and other metal sulfides (pyrite, pyrrhotite, chalcopyrite, and sphalerite) where isomorphic substitution occurred. Cobaltite is mainly distributed at the periphery of the skarn alteration zone with more pyroxene. The isomorphic substitution content of Co in pyrite (2.43–3.05 wt%), pyrrhotite (1.87–2.47 wt%), chalcopyrite (0.63–1.38 wt%), and sphalerite (0.73–0.90 wt%) is high. The negative correlation between Co + Ni (wt.%) and Fe (wt.%) suggests that Co + Ni replaces Fe in pyrite and pyrrhotite. The weak correlation between Co (wt.%) and Cu or Fe (wt.%) indicates th...