Abstract:

The magmatic activity could be divided to two stages in Chengchao ore district,Hubei：diorite in the early stage and granite in the latter stage．The magma intruded in the mid-late Yanshanian period．The correlation between the magma and mineralization is consanguineous and the Yanshanian magma is the source of ore-forming materials．The mineralization period could also be divided to two stages：magnetite ore in the early stage and metal sulfide ore in the latter stage. Magnetite stage is the main stage for mineralization．The contents of rare earth elements indicate that the chondritenormalized REE and LREE patterns of diorite have the strong reversed change with that of magnetite ore．Such a case also occurs between granite and metal sulfide ore．The moderate-strong depletion of Eu in granite and metal sulfide ore is the result of the crystallization of diorite and the mineralization of magnetite．In addition，the contents of trace elements indicate that in diorite it is rich in Cr，which belongs to chalcophile elements，and this is because of the mineralization of magnetite ore and the separation of Fe ³⁺ in the early period；it is rich in Co,Ni in granite，belonging to siderophile elements，which is related to the mineralization of metal sulfide ore．We could draw the conclusion that the metallogenic elements are mainly derived from diorite magma，which is consistent with the other skarn type iron deposits in southeast Hubei Province．This research may play an important role in summarizing the metallogeny in the area of southeast Hubei Province．  

Key words: ore-forming materials, geochemistry, Yanshanian magmatic rock, Chengchao iron deposit, southeastern Hubei Province