南岭地区多金属矿床铅同位素组成差异分析

Lead Isotope Composition Difference Analysis of Polymetallic Deposits in Nanling

南岭地区是我国多金属矿床重要的基地,为了解该区多金属矿床成矿物质来源特点方面的差异,选择利用铅同位素示踪技术,对区内黄沙坪、宝山、凡口、大宝山、大厂5个不同多金属矿床成矿物质来源特征进行统计分析。结果表明,黄沙坪、宝山、大宝山3个多金属矿床中铅的来源相同且形成于燕山运动第一次成矿期高峰期（180~155 Ma）,凡口、大厂2个多金属矿床铅的来源相同,形成于燕山运动第二成矿高峰期（115~90 Ma）。南岭地区多金属矿床形成的构造背景与华南地区中生代处于拉张构造背景一致,多金属矿床的形成是晚中生代以来华南地区岩石圈伸展作用的结果。

One of the important polymetallic deposits base of China is in Nanling area,in order to illustrate the feature difference among the sources of ore-forming materials of the polymetallic deposit in this area, the ore-forming material sources of the polymetallic deposits within the area, such as Huangshaping,Baoshan,Fankou,Dabaoshan,Dachang,are statistically analyzed by using of the lead isotope tracing technology. The results show that the polymetallic deposits of Huangshaping,Baoshan,Dabaoshan are formed in the first mineralization peak of Yanshan movement（ 180 ~ 155 Ma）,the remaining two polymetallic deposits are formed in the second mineralization peak of Yanshan movement（ 115 ~ 90 Ma）. The tectonic background of polymetallic deposits in Nanling region is the same as the Southern China region in the Mesozoic extensional tectonic background,the formation of polymetallic deposits is the result of late Mesozoic lithospheric extension in Southern China.