Rock Characteristics Of Granite In Yuerya Of Hebei And Its Relation With Gold Deposit

This paper is based on petrology, deposits, and ore-forming systems theory as the theoretical basis, Geological field investigation and laboratory analysis, Geology and geochemistry, stable isotope and geological dating method of combining multi-disciplinary.The study suggest that yuerya gold have a simple ore mineral, the mineralization types can be divided into Fine disseminated pulse type and vein type in general; Wall-rock alteration have sericitization, pyritization, siliconization, of potassium, etc, and sericitization is main prospecting marks. According to the mineral association combination and mutual relationship, the mineralization is divided into four stages, the main metallogenic age is yanshan period.Yanshan period of granite is main exposed in Mining area. Yuerya rock mass, a pulse type double entry rock mass, is composed by fine particle white in black mica granite (hereinafter referred to as white granite) and coarse material in red granite potassium long (hereinafter referred to as the red granite). White granite is early phase, red granite is late phase. Through to the rock mass mineralogy, petrology, geochemistry characteristics study showed that Yuerya rock mass is alkaline type A granite, light rare earth high degree of fractionation, belong to shell source of the formation of the partial melting of granite, granite tectonic environment belong to make the class after granite (POG), and the late red granite closely related to mineralization. According to the exploration EH4 continuous conductivity measurement line study, Yuerya rock mass have concealed rock mass in the lower, rock mass form should be up small down big, displaying that Yuerya rock mass deep gradually become swollen to the granite rock mass.Through the molybdenite Re-Os isotopic dating method and stable isotopes of research show that:in time, metallogenic age is 167 Ma or so, later than rock formation age; In the space, strictly control the distribution of rock ore cloth, for gold mineralization provide enough let ore space; In the formation, diagenetic and metallogenic source material is same, both are from magma system which is between the upper crust and lower crust, magma provide enough metallogenic heat source and material sources. As a result, rock mass is closely related to mineralization, the ore-forming geological effect mainly for magma ore-forming geological effect.