摘要
在六批叶沟金矿石中,精选出与金矿物同期生成的绢云母作为样品,采用40Ar_39Ar快中子活化法测年,获得8个一致相连的平坦型绢云母年龄谱,tp=(190.28±0.30)Ma,氩同位素计算得等时线年龄为(189.98±0.58)Ma,两者完全吻合。等时线截距为(296.9±10.0)Ma,与大气氩的该值(295.5Ma)相比较,两者完全吻合,表明该样品出自未受明显后期热力作用影响的非扰动体系。锁定六批叶沟金矿床主要成矿年龄为190Ma左右,属早侏罗世的燕山早期。
Sericites formed at the same stage as ores in the Liupiyegou gold deposit were used as samples. Using the 40 Ar_ 39 Ar fast neutron activation dating method, the authors got 8 concave and middle_high temperature age charts 〔 t p=(190.28±0.30) Ma〕, which are connected, consistent and in accord with the Ar isotope isochron age (189.98±0.58) Ma. The intercept of the isochron is (296.9±10.00) Ma, which is well consistent with the data of atmospheric Ar (295.5 Ma). It is shown that the samples were collected from a system which had not been subjected obviously to the influence of later thermodynamic action.The metallogenic age is 190 Ma, thus belonging to Jurassic.
出处
《矿床地质》
CAS
CSCD
北大核心
2004年第4期502-508,共7页
Mineral Deposits
基金
国家矿产资源勘查项目(2001-882)的资助