Characteristics and origin of the Zhulazhaga gold deposit in Inner Mongolia, China

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• 作者：Chengwu Ding^a ; ^b ; ^{dingchengwude@163.com" class="auth_mail" title="E-mail the corresponding author} ; Fengjun Nie^a ; Sihong Jiang^a ; Yifei Liu^a ; Yi Cao^a
• 关键词：Zhulazhaga gold deposit ; Magmatic&ndash ; hydrothermal ; Northern margin of the North China Craton ; Metasedimentary rocks ; Hercynian tectono-magmatism
• 刊名：Ore Geology Reviews
• 出版年：2016
• 出版时间：March 2016
• 年：2016
• 卷：73
• 期：part_P2
• 页码：211-221
• 全文大小：2368 K

文摘

The Zhulazhaga gold deposit in the northern margin of the North China Craton (NCC) is a large tonnage hydrothermal deposit with a reserve of about 50 t at about 4 g/t Au. The deposit is characterized by an epigenetic style of mineralization in metasedimentary rocks dominated by slates, low-grade metamorphic clastic rocks and minor volcanic rocks. Gold mineralization is dominantly controlled by structures, manifested by stratabound orebodies located immediately to the east and west of a major N–S-trending fault and associated extensional fractures and NE-trending fault zones. The mineralization is also preferentially located in the fourth sub-member of first member of the Agulugou Formation. There are many auriferous quartz veins parallel to the bedding of the host rocks which contain the orebodies, and high-grade ore preferentially occurs near to these quartz veins. The structures provided pathways for transportation of gold-bearing fluids within the formation that appears to form a particularly favorable host rock and depositional setting.

Hydrogen and oxygen isotope data indicate that ore-forming fluids were dominated by magmatic water mixed with minor meteoric water. Sulfur and lead isotope data indicate that some sulfur and lead came from the magmatic fluid. The metallogenic age (280 Ma) of this deposit and the crystallization age (280–290 Ma) of the granite porphyry in the district indicate a link between the Hercynian magmatism and gold mineralization. The Hercynian tectono-magmatism and associated hydrothermal activity remobilized gold and drove ore-forming fluids to the favorable depositional environment.

The northern margin of the NCC is prospective for gold mineralization hosted in metasedimentary rocks which may be one of the most important deposit types for future gold exploration in northern China.