Ore-controlling Factors of the Beichagoumen Ag-polymetallic Deposits in Northern Hebei Province

The Beichagoumen Ag-polymetallic ore deposit was found in the end of last century,and the new Ag and Pb-Zn deposits were discovered again during the Great Geological Survey resent years in the old ore field.There is very good ore-hunting expectation in the area.The deposits are controlled by the structure-magma factors.There are three types in the structure ore-controlling factors: faults,volcanic edifices and unconformable interfaces.And there are two types in the magma ore-controlling factors: porphyritic bodies and sub-volcanic bodies.The structure ore-controlling factors are the most important ones.Varieties of ore-controlling factors are found in the different deposits.The characters of the different deposits is summarized on geology,geophysics and geochemistry.