The Features Of Dyke And The Relationship Between Dyke And Mineralization In The Aiziwangjia-Yuantuan Gold Deposit

Zhaoyuan city located in Jiaodong peninsula, East China, is one of the most important gold production district, in which the storage and amount of gold rank first among the whole counties in China.In current paper, the Aiziwangjia-Yuantuan district was chosen as a study area to analyze the condition of gold mineralization. The petrology, structural geology, mineral deposit, isotope geochemistry and geochemistry of mineral deposits, and relevant analytical methods were used to characterize the regional mineralogy nature and geochemical features of dykes. Then the relations between dykes and gold-forming with respect to the geological characters of gold deposit are investigated.The domain of dyke in the given area is consist of hornblende-orthophyre, orthophyre, granodiorite-porphyry, diorite, lamprophyre, granite porphyry, gabbro, and mineralize -granodiorite by means of systematic field survey and inside job.The results of geochemical features of rare trace element and trace element of the country rock, the characters of wall rocks near ore, vein and ore body, and the analysis of sulfur isotope and hydrogen and oxygen isotope show that the sulfur in dyke and ore body derived from deeper crust, and ore-forming fluids is a mixture of magmatic hydrothermal fluids and meteoric water.The gold mineralization is related with the dykes, which is demonstrated by the characters of dykes, regional nature of ore body and regional gold shattered fault belt industrial ore body. Accompanying intrusion of the dykes, which should make the fault belt became the structural weak zone and be favorable for the cycling and precipitation of the ore fluid. Hornblende-orthophyre, diorite in the mineralizing phase and early lamprophyre are closely related with gold mineralization. The favorable areas of mineralization are located in where the strikes of the dykes transfer from NE or NNE to NNE or NE.