大兴安岭西坡及邻区银铅锌矿床成矿作用若干问题的讨论

MAIN CHARACTERISTICS OF Ag-Ph-Zn DEPOSITS AND DISCUSSION ON THEIR MINERALIZATION ON THE WESTERN SLOPE OF THE GREAT HINGGAN MOUTAINS,NE CHINA AND NEIGHBOURING AREA

Continental volcanic Ag--Ph--Zn deposits widely occur in belts and groups in the bordering region among Russia, Mongolia and China. There are a lot of large and superlarge deposits in the region. This paper summarizes main characteristics of this type of deposits onthe western slope of the Great Hinggan Mountains, NE China and its neighbouring regionEmphasis is put on several important problems about genesis and metallogenic regularities ofthis type of deposits, such as mineral sources, metallogenic series and ore--controlling factors. Authors consider that these Ag--Ph--Zn deposts in fact constitute a Ag--Ph--Zn metallogenic series related to the Late Jurassic and Early Cretaceous volcanic and subvolcanic magmatic activities in the bordering region amony China, Russia and Mongolia. The large scaleof Late Jurassic and Early Cretaceous volcanic and subvolcanic alkali--enriched magmatic activities are the essential reason and material basis for the mineralization of Ag--Ph-Zn deposits(probably including Cu,Mo,Sn deposits, etc. ) in the region. These magmatic activities alsoreflect the geochemical process of material differentiation, concentration and evolutionthrough the deep crust--mantle interaction.