南岭构造带东段构造岩浆演化与铀成矿关系

RELATIONSBETWEEN TECTONO—MAGMATIC EVOLUTION AND URANIUM MINERALIZATION IN EASTERN PART OF NANLING TECTONIC ZONE

南岭构造带东段自震旦纪以来经历了四次“开合”演化旋回 :早震旦世—志留纪“开合”旋回 ,形成了以震旦系和寒武系为代表的基底铀源层 ;中泥盆世—三叠纪的“开合”旋回 ,造就了二叠系铀源层及印支期铀源体 ;侏罗纪的“开合”旋回 ,再造了燕山期的富铀源体 ;白垩纪—第三纪的“开合”旋回 ,提供了铀成矿热液和成矿空间 ,促使铀聚集成矿 。

The eastern part of Nanling tectonic zone has exposed to ‘Opening’ and ‘Closing’ evolutional cycle for four times ever since Sinian Period.They are ( with a chrono- logical order) :the‘Opening’and‘Closing’cycle of Early Sinian Epoch— Silurian Period, which forms the base uranium source layer of Sinian System and Cambrian System;the ‘Opening’ and‘Closing’ cycle of Middle Devonian Epoch— Triassic Period,which forms the Permian uranium source layer and the Indo— Sinian Period uranium source granite;On the basis of the above two processes,the‘Opening’and‘Closing’cycle of Jurassic Period built the uranium enriched source granite;whereas the‘Opening’ and‘Closing’ cycle of Creta- ceous Period—Tertiary Period,facilitate the mineralization of uranium by providing abundant minerogenic hydrothermam fluid well as space.Thus the distinguished Nanling Ore- bearing Zone came into being.