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铜厂闪长岩体位于扬子地台北缘勉县-略阳-阳平关三角地块区域内,主要由闪长岩、石英闪长岩和花岗闪长岩组成。LA-ICPMS和SHRIMP锆石U-Pb同位素定年结果表明铜厂闪长岩体存在3个侵位结晶阶段:早期阶段的闪长岩形成于879±7 Ma;中期阶段的石英闪长岩形成于848±5～840±7 Ma,含矿钠长岩脉于834±7 Ma侵位结晶,与中期阶段石英闪长岩侵位时代在误差范围内一致;晚期阶段花岗闪长岩形成于824±5 Ma。这些新的年代学数据表明铜厂闪长岩体及其相伴生的大型铜厂铜矿形成于晋宁期,而不是古生代,揭示了扬子地台北缘存在重要的新元古代早期岩浆活动,与Rodinia超大陆的裂解事件在时间上(860～750 Ma)基本一致,是Rodinia超大陆事件在扬子地台北缘的重要响应。
The copper plant diorite body is located in the Mianxian-Lueyang-Yangpingguan delta block on the northern margin of the Yangtze Platform, and is mainly composed of diorite, quartz diorite and granodiorite. The results of LA-ICPMS and SHRIMP zircon U-Pb isotopic dating show that there are three emplacement stages in the copper plant diorite body: the early-stage diorite formed at 879 ± 7 Ma; the middle-stage quartz diorite formed at 848 ± 5 ~ 840 ± 7 Ma. The ore-bearing bryophyte vein emplaced at 834 ± 7 Ma, consistent with the emplacement age of quartz diorite in the mid-stage within the error range. Late granodiorite formed at 824 ± 5 Ma. These new chronological data indicate that the copper plant diorite body and its associated copper plant are formed in the Jinning Period instead of the Paleozoic, revealing that there is an important Neoproterozoic magma activity in the northern margin of the Yangtze Platform, The cracking events in the Rodinia supercontinent are basically the same in time (860 ~ 750 Ma) and are an important response of the Rodinia supercontinent to the northern margin of the Yangtze platform.