The mixing of Mesozoic crust-mantle magma is the key to the source of large amounts of gold deposits in the Jiaobei uplift, China

The huge material source of gold deposits in Jiaodong area has always been the focus of academic debate, and it is difficult to find convincing evidence. In the absence of other more effective direct proof of the source of huge gold, this paper indirectly draws the conclusion that the huge gold comes from the mixing reaction of Mesozoic crust-mantle magmas based on the variation law of large amounts of trace elements geochemical data from fresh rocks of main geological bodies in Jiaobei area. The mixing reaction and evolution of the Guojialing and Weideshan crust-mantle magmatism may be the main mechanism for the formation of huge gold source, and it is also the source of heat supply. Linglong granite may be a small amount of gold supplier and the main ore-hosting geological body. The main metallogenic time of gold deposits in Jiaodong area (130 similar to 105Ma) is the same as the evolution and crystallization time of granite magma of Guojialing (130 similar to 125Ma) and Weideshan (126 similar to 108Ma) granites, which means they are closely related. During magma mixing reaction and condensation period, magmatic hydrothermal fluids ascending, migration, and precipitation mineralization. The Mesozoic geological bodies inherited geochemical environment of Early Precambrian in this area. The Mesozoic crust was mixed with a large amount of mantle materials, and the Au abundance was high, averaging 1. 31 x 10(-9), which was a geochemical high background.