东南地洼区铀成矿省的划分及其特征

DIVISION OF URANIUM METALLOGENETIC PROVINCES AND THEIR CHARACTERISTICS IN SOUTHEASTERN DIWA REGION

The Southeastern Diwa region is an important concentrated area of uranium mineraliza-tion in China.(The industrial reserves proved make up the two-thirds of the total reserves in the coun-try).The region is located in the east of the southern edge of east-Asia crust and classified into fivesecond-class tectonic units and four uranium metallogenetic provinces according to the features of itsgeology,geophysical-chemical field and uranium mineraliztion and the difference of crust evolution-movement history. Both fall into some correspondency each other,i.e.the different tectonic unit pos-sesses a definite metallogenetic exclusiveness and bears some important types of uranium mineralizationfor prospection. However,the formation and distribution of uranium deposits are controlled by the re-gional crustal evolution,especially associated with the tectonomagmatic activities at Diwa stage. Theenvironment and space for the emplacemant of ore bodies is not only passively supplied through tecton-ics which controll the distribution of regional uranium mineralization,but also participate the process oflmineralization and controll the genesis of the concerning mineral-deposits.They play a vital role in theformation of polygenetic comlpound uranium deposits which exhibit the characteristics of strata-boundand rock-source within the region.