Metallogenetic Characteristics Research Of Molybdenum And Lead-zincin In Qianjia,hainan Province

The region of Qian Jia is in the the southwest of Hainan island,it located in intersection area which is betweent the deep falut of LingShui-JiuSuo and the fault depression of BaiSha.In recent years,with the basic geological prospecting and the ore-forming metallogenic regularity of a large proportion progressing.In southwest of Hainan island,There has been found numerous deposits with favourable metallogenic prospects,it may exhibit the ore-forming metallogenic regularity.The ore genesis of deposit and the temporal spatial distribution of deposit were related to the mesozoic magmatism-tectonic movement,they are always densely distributed by the edge of igneous rock body. However,the region of Qianjia were affected by the regional metallogenic geological factors,it also showed some distinctive features: depoists are always densely distributed on igneous rock body;the molybdenum mineralization has associates with lead-zinc.Based on the analysis of the previous study,with geological prospect. Comprehensive useing petrology、mineral deposits、Geochemistry, geophysics、mineralogy、isotope geology and metallogenic prediction,for explore the ore-forming metallogenic regularity of Qianjian areas. First of all, based on regional geological background,carefully realize the geology in the Qinjia area. then on this basis,contrast the geological characters of typical deposits which are pertain to the hill of Shimen mo-Pd-Zn deposite and the hill of Houwan Pd-Zn deposite with the hill of Kanshu Ag depsite.These three types of ore deposits Preliminary has found common with the molybdenum、lead、zinc ore occurrence:Mineralization associated with late porphyry intrusion activities;Deposits were obviously controlled by NW-NS fault,and the ore bodys wall rock were granitoid; the degree of mineralization were positively associated with the wall rock alteration,ore structure has been disseminated, fine vein, brecciated filling. In the study area,These deposits(ore occurrence) commontion has in a certain ore-forming geological background limit,by the same ore-forming driving force to form a series of similar, space and time related causes of the different elements of combination ore deposit. Based on the ore deposits(ore occurrence) observe carefully, explore the ore-forming metallogenic regularity by the point for the face way:1.Though formation in the area is the main ore-forming factors,there are limited in the study area that wouldn’t mainly mineralization.2.Magmatic rocks are form the mainly granite type multiphase intrusion rock mass of Qinjia,and the late along the fracture porphyry. The magmatic rocks mass size up the molybdenum-lead-zinc basic geological characteristics of Huanan area in China. The main trace elements analysis shows that Qianjia magmatic rock mass through physical and chemical changes in the environment during the diagenetic process, after the diagenetic strongly weathering;Under these background,the late intrusion porphyry can differentiation molybdenum fluid,with drive fluid circulation extraction lead-zinc metallogenic element under a certain space.3.The NW-NS faulting time was coupling porphyry intrusive,tensile fracture space to provide space for porphyry intrusion and mineralization, fracture with multiple faulting time would easy to form a semi-closed system that is conducive to molybdenum、lead、zinc deposit.4. Under the influence of Magma and fracture,the mineralizationand zone and wall rock alteration has regularity, Vertical zoning can present a deep molybdenite and planar greisenization alteration to shallow lead-zinc mine and vein sericitization three-dimensional combination of silicified alteration belt. In the plane because porphyry intrusion path is different;The closer the deep magma of the roof area porphyry easy differentiation out of the high temperature fluid, corresponding the area of high temperature and mineralized alteration.5.There is no evidence by porphyry and wall rock has the UST quartz,that shows fracture system is a semi-closed environment. Porphyry invasion did not accompany amounts of fluid from magma chamber. So the fluid in the area is dominated by porphyry emplacement which dissolving fluid. Magmatic condensation out early dissolution fluid make molybdenum elements migration and precipitation under the environmental impact of pressure reducing enrichment. Late magmatic condensation of soluble lead and zinc and the temperature drop of fluid extraction environment under the influence of concentration.