Study On The Ore-forming Geological Process In Niuxinshan Section Of Hebei Huajian Gold Deposit

Huajian gold deposit is located in Kuancheng manchu autonomous county of hebei province. It was undergoing serious resource crisis for long-term exploiting. Rescent years deep mine prospecting in this area shows good prospecting effect and huge potencial in the deep of the gold deposit. It is necessary to carry out further research work on the gold deposit.Based on the previous work, with the study of the regional geological background, geological characteristics, rock-control and ore-control structures, geochemical characteristics of Niuxinshan granite, diagenetic age, ore-forming fluid, mineralization substances origin, the ore-forming geological body, metallogenic evolution and ore prospecting direction in Niuxinshan mining area of Hebei Huajian gold deposit,we get the following seven achievements:(1) It is the first time putting forward the white biotite-granite, which is located in the center of Niuxinshan granite, is the early magma. The red moyite which is located in the edge of Niuxinshan granite is the the later period. Zircon SHRIMP U-Pb dating indicates that, the intrusive age of early magma is about 185Ma and the later is about 155Ma. The early zircon were Involved in the later magma. (2) It is summed up the second period moyite more closely related to mineralization. (3) With the study of the ore-control structures, the author believes that Huajian gold deposit is controlled by folding and faulting. Basement fold and mantle fold have jointly controlled the formation of Niuxinshan granite, quartz vein in Niuxinshan mining area is controlled by NNE trending fracture. (4) It is summed up the ore-forming geological body is Niuxinshan granite. Based on the ore-forming geological body, metallogenic evolution model is established. (5) The ore-forming fluid is discussed. It proposes that Huajian gold deposit is basically belong to middle temperature warm liquid ore deposit. The ore-forming fluid of Huajian gold deposit possessing the characteristics of middle temperature, low-density and low salinity. The mineralization depth is about 6.3km. (6) Through the discussion of the ore-control structures and the genesis of the deposit, the author believes that the next step ore prospecting should be focused on the Niuxinshan granite contact in the depth and the depths of the quartz vein which is located in northeast of Niuxinshan granite.