Chengde Fengning Niujuan Silver Deposit Genesis Analysis

Niujuan silver deposit in Hebei province is located in the Fengning County fourforks Township, located in the North Taipei tectonic position margin of Jurassic in theeastern margin of four fork volcano raised end, NNE shanghuangqi-Oolong ditchtectonic magmatic belt.The mine in the granite fracture belt, wherein the ore-bearing rock is slurryexplosive breccia. Silver pyrite, sphalerite, galena and enrichment of close contact. Inaddition to elemental silver, lead, zinc, accompanied by a certain amount. Thecharacteristics of ore-forming elements is the upper part of the lower part of silver,lead and zinc with vertical. The test of ore and rock in major elements, trace elementsand rare earth elements and fluid inclusions, systematically discusses thecharacteristics of the ore deposit.Through the study of the regional geological background system of deposit, it isthe basement metamorphic rocks in this area, the target layer is mainly composed oflimited distribution, Neoarchean HongQiYingZi rock group, Proterozoic metamorphicintrusive rocks. Metamorphism from early to late to low amphibolite facies,greenschist facies regional metamorphism. Zone metamorphic terrane experienceddeformation multi-tectonic superposition. This paper describes in detail thecharacteristics of the ore deposit, ore mineral composition, structure of ore and rockalteration are expounded.Deposit the area is the Yanshan movement period, more intense magmatism,acidic magma derived from the upper mantle along the upper Yellow-Oolong ditchdeep fracture intrusive rise, forming a shallow intrusive or volcano eruptionmechanism, formation of Mesozoic volcano rock. Volcano near the passageway is theformation of porphyry or breccia. A closed space is formed near the surface, volatileaccumulation, the surrounding rock pressure is greater than the outside, has thecryptoexplosion, formation siliceous breccia, the sulfide and silver gold deposit.Based on the "Chengde area of Hebei province polymetallic metallogenic law,precious metal deposits and prospecting direction of research" project, based on fieldobservations, in-depth analysis of the previous research data, view of origin andsupporting evidence collection and summary of Niujuan deposit currently approved,analysis of the causes of differences of views and inadequacy, add rock the ore sampletest analysis, put forward their own point of view. At the same time, based on theprediction of ore bodies in the deep part and periphery prospecting potential analysis.The full collection and understand the basis of Fengning-Chengde cow geologicalresearch results, through the existing research data and field investigation results, thatthis study can be concluded that the silver and gold ore deposit, the ore-formingmaterial source of polymetallic deposit, ore-forming process and evolution, formation model of prospecting systematic summary, further determination of metallogenicmechanism and the genesis of the deposit, the prospecting significance.