Geological-geochemical Characteristics And Deep Metallogenic Prospect Of Fluorite Deposit In Chenlou,southwest Henan Province

The fluorite deposit area in Song County,Henan Province is located on the polymetallic and fluorite metallogenic belt in the southern margin of the North China Craton,and is adjacent to the Qinling fold system.The fault structure in the area develops,and the magmatic activity is intense and frequent,the ore-forming conditions are superior.Based on the geological and geochemical characteristics of the deposit,the Chenlou fluorite deposit is considered to be a medium-low temperature hydrothermal fluorite deposit in the F3 fault zone of the Taishanmiao rock mass.The main metallogenic epoch was late Yanshanian.The main results of the paper are as follows:?1?The ore-controlling structure,ore body morphology,ore structure and mineral symbiosis combination were studied,and the wall rock alteration zoning was divided,and the ore body sideways rule was determined.The east-west F3 fault structure is the main ore-controlling factor of the deposit,and it is also the focus of the next exploration of the ore.?2?Dividing the hydrothermal metallogenic stage: I The quartz vein stage,in which quartz veins have been destroyed by late structure and high-pressure gas-liquid blasting,only angular quartz fragments and tectonic breccia are seen,and are covered by later hydrothermal minerals.Granite tectonic breccia has undergone strong alteration and is surrounded by fluorite secondary zonal zone;II Early fluorite stage,the white and purple fluorite formed during this stage envelops the first phase of quartz shards or tectonic breccia,forming a firefly.The quarry body is small in size and low in grade,and does not constitute a major ore body.III late fluorite?main?metallogenic stage,the first two stages of cementation are characterized by light green,light purple,light-red lumps and veins.Ore rock is the main metallogenic stage;IV Carbonate stage,a small amount of carbonate veins are filled into the ore body or fracture,which is a sign of the end of the mineralization.?3?Determined the cause of the deposit.Research on rare earth elements shows that fluorite mineralization is closely related to magmatic intrusion.The fluid inclusion study determined that the homogenization temperature of the main metallogenic stage was 123.2?³49.5?,with an average of 187.7?.The overall performance was characterized by shallow,medium and low temperatures,low salt,low density,and CO₂ depletion;zircon U-Pb dating showed that The Heyu complex rock masses experienced at least three intrusive superpositions of 143.1 Ma to 144.4 Ma,128.1 Ma to 134.5 Ma,and 124.7 Ma to 127.2 Ma.The isochron age of fluorite Sm-Nd dating is 120 Ma ± 17 Ma.The metallogenic era was later in the late Jurassic and after the last intrusion of the Heyu complex rock.This indicates that the type of deposit is a medium-low temperature hydrothermal fluorite deposit associated with sub-volcanic hydrothermal fluids.?4?Divide the axial zoning sequence of the fluorite deposit,from top to bottom Sb-Mo-F-Ca-Ce-Ag-As-Ba-Y,“reverse zoning”phenomenon,combined with the main mine the phenomenon that the denudation parameters of the body gradually increases in the depths suggests that the ore body has extended to the deep or there is a blind ore body;combined with the study of the ore-forming rules,it is believed that the deep part of the ore body and the direction of the tectonic belt in the strike?east and east sides?have better prospecting prospects.