~(40)Ar-~(39)Ar Fast Neutron Activation Dating Method for Sericite from Liupiyegou Gold Deposit, Jilin Province
Hou Shuhuan 1 and Sang Haiqing 2 (1 Jilin Institute of Geological Exploration for Nonferrous Resources, Changchun 130021, Jilin, China; 2 Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China)
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.