Trace Element and Sulfur Isotope Compositions of Gold-bearing Pyrite from the Zhangjiawa Iron Skarn Deposit,Laiwu District:Implications for Sources of Early Cretaceous Gold Mineralization in the North China Craton

摘要

Objective The Zhangjiawa iron deposit is the largest-tonnage and representative iron skarn deposit,with proven reserves of 290 Mt at an average of 46%Fe(up to>65%),in the Laiwu district,eastern North China Craton(NCC)(Figs.1 a,b;Duan and Li,2017).Iron mineralization at Zhangjiawa is mainly hosted along a northern contact zone between the Kuangshan dioritic intrusion and Middle Ordovician carbonate rocks that host numerous evaporite intercalations(Figs.1b,c).