摘要
Tongchang dioritic pluton in Southern Shaanxi Province is located in the tectonic domain of the Mianxian-Lueyang-Yangpingguan triangle block, northern margin of Yangzi Craton, and consists mainly of diorite, quartzdiorite and granodiorite. Zircon grains separated from these rocks are dated using LA-ICPMS and SHRIMP U-Pb isotopic methods. The results indicate three intrusive stages of the Tongchang dioritic pluton, and early diorite emplaced at (879±7) Ma; middle quartz diorite at (848±5) Ma to (840±7) Ma, with copper ore-bearing albitite emplaced at (834±7) Ma, which is consistent with the crystallization age of quartz diorite within error range, and the last granodiorite at (824±5) Ma.