Study On Geological And Geochemical Prospecting Models Of The Main Porphyry Molybdenum Desposits In China

Molybdenum deposits as one of 6 traditional dominant Chinese minerals,widely used in metallurgical and chemical industry fields,have special significance for Chinese national economy and social development.In recent years the demand of the international market for molybdenum is continually increasing.However,China as a major exporter of molybdenum,which has a low level's study of molybdenum deposits,didn't have rational exploitation and utilization of molybdenum ore resources and made the available life of molybdenum mine shortened.Therefore,strengthening theoretical study of molybdenum ore prospecting models for rational exploitation and utilization of molybdenum ore resources in China is necessary.Porphyry molybdenum deposit is the main type of molybdenum deposits and the most important source of molybdenum ore resources.The proved reserve of molybdenum metal have 70%percent of the total reserve in China.Porphyry molybdenum deposit mainly locates in East Qinling metallogenic belt,Yan-Liao metallogenic belt and Lesser Xing'an Range-Zhangguangcai Range metallogenic belt.Study on its geological and geochemical prospecting models is of great significance for the Chinese geological exploration of molybdenum deposits.This study takes porphyry molybdenum deposit as a research object,depends on the information of the project which named the evaluation of national resource potential from China Geological Survey and combines the research results from the predecessors.Through the study on geological and geochemical characteristics of two main Chinese porphyry molybdenum metallogenic belts which include East Qinling metallogenic belt and Yan-Liao metallogenic belt,and the synthesized analysis,making the following results:(1)Porphyry molybdenum deposits of two major molybdenum ore concentration areas are mostly formed in the continental collision orogenic environment and intracontinental orogenic environment.(2)Deep fault and regional fault are the main ore-controlling structure of porphyry molybdenum deposit.The intersection part of this two groups of faults is the most favorable position where porphyry molybdenum deposit occurs.(3)Metallogenic epoch is mainly Yanshanian period.The host strata are Precambrian old strata and Proterozoic strata are the main ore prospecting marker horizon.(4)Specific annular surface wall rock alteration zoning is the favorable ore prospecting marker.(5)the ore-bearing rock body is usually strong acidic rock with high silicon,high alkalinity and high potassium.(6)Regional geochemical characteristics show the association of ore-forming elements is Mo?Bi?W?Sn?Cu?Pb?Zn?Ag?As?Sb?Cd?Au?Mn etc.Element distribution exists horizontal zoning,Mo?Bi?W?Sn are usually located in the centre of ore body and other elements are located at the edge of ore body.(7)The limited middle-large scale geochemical prospecting datas of the ore area indicate that the association of ore-forming elements is Mo?Bi?Cu?Pb?Zn?Ag?As?Au etc.Element distribution exists horizontal zoning,Mo?Bi are usually located in the centre of ore body and other elements are located at the edge of ore body.