Geochronology and Significance of Granites Associated with Gold Deposits in the Jidong Area, China

查看全文 作　　者：Neal [1]MCNAUGHTON;David [1]GROVES 机构地区：[1]Department of Geology University of West Australia, Australia,Department of Geology University of West Australia, Australia 出　　处：《Acta Geologica Sinica(English Edition)》索引2000年第74卷第2期,共5页 摘　　要：The Jidong area is located on the north margin of the North China craton. It is a nucleus composed of the oldest rocks in China. Precambrian metamorphic rocks with various Phanerozoic granitoids invaded are widespread. Gold deposits here have close spatial relations to granitoids. Some deposits occur within them and others in the outer zone of the contact belt of the intrusion, extending thousands of metres. There have been controversial views in regard to the relations of the deposits to the intrusions although traditional techniques have been used to date the intrusions. In order to solve such a problem, the SHRIMP technique was adopted to date the U-Pb ages of zircon collected from the Yuerya intrusion which hosts the large-sized Yuerya Au deposit and Qingshankou intrusion 2 km away from the Jinchangyu (larger-sized) Au deposit. Analysis shows that the ages of 175±1 Ma and 174±3 Ma for Yuerya intrusion and the age of 199±2 Ma for Qingshankou granite indicate the Early Yanshanian stage of the Meso- 关 键 词：SHRIMP GEOCHRONOLOGY GRANITE YANSHANIAN East China