Gondwana Research, 2009, 16: 264-271

A Re–Os study of molybdenites from the Lanjiagou Mo deposit of North China Craton and its geological significance

Chunming Hana,Wenjiao Xiaoa, Guochun Zhaob, Min Sunb, Wenjun Quc and Andao Duc

Abstract

The Lanjiagou Mo deposit is located in the eastern part of the North China Craton. Rhenium and osmium isotopes in molybdenites from the Lanjiagou porphyry Mo deposit have been used to determine the timing of mineralization. Molybdenite was analyzed mainly from granite porphyry, which is characterized by moderate to strong silicification. Rhenium concentrations in molybdenite samples are between 33 and 48 µg/g. Analysis of eleven molybdenite samples yields an isochron age of 181.6 ± 6.5 Ma (2σ). Based on the geological history and spatio-temporal distribution of the granitoids, it is proposed that the Mo deposits in the eastern part of the North China Craton were related to the subduction of the Paleo-Pacific plate during Jurassic time.