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汇集了华北地台北缘 2 1个金矿床的 45个直接测年数据 ,对这些数据的可信度作了评述。选用矿石或蚀变围岩中的绢云母、黑云母、钾长石等蚀变矿物作为测年对象 ,采用 Ar- Ar、 K- Ar法或 Rb- Sr等时线法测年在目前的技术条件下是经济可行的 ,关键是要保证被测矿物确为蚀变矿物并且纯度较高。用 U- Pb法测定矿脉中的水热锆石来确定成矿年龄 ,但如何区分继承锆石和水热锆石尚不成熟。以地质观察为基础 ,充分利用上述测试数据 ,认为区内的火山浅成低温热液金矿床和多数侵入体接触带内外的金矿床成矿时代为燕山期 ;夹皮沟金矿床的成矿时代为海西期 ,可能叠加有燕山期的矿化 ;冀东金厂峪金矿床存在早期前寒武纪和晚期中生代矿化的叠加 ;张宣和乌拉山地区的金矿床成矿时代可能为燕山期 ,有待进一步研究确定。
A total of 45 direct dating data from 21 gold deposits in the northern margin of the North China Platform have been collected and the credibility of these data has been reviewed. Selected ore or alteration surrounding rock sericite, biotite, potash feldspar and other alteration minerals as dating objects, using Ar-Ar, K-Ar method or Rb-Sr isochronometry in the current technology It is economically feasible under the conditions that the key is to ensure that the mineral under test is indeed an altered mineral and of high purity. U-Pb method was used to determine the hydrothermal zircon in the veins to determine the metallogenic age, but how to distinguish between succession zircon and hydrothermal zircon is not yet mature. Based on the geological observation, taking full advantage of the above test data, it is concluded that the mineralization age of the gold deposits in the volcanic epithermal gold deposits and the most invaded intrusions in the area is the Yanshanian period. The mineralization age of the Jiapigou gold deposit For the Hercynian period, Yanshanian mineralization may be superimposed; the gold deposits in the Jichangyu gold deposit in the Jidong area were superimposed by the early Precambrian and late Mesozoic mineralizations; the gold mineralization ages in the Zhangxuan and Wulashan areas may be Yanshan Period, pending further study to determine.