华南重要金属矿床的成矿规律——时代爆发性、空间分带性、基底继承性和热隆起成矿

华南热液矿床形成的时代爆发性、空间分带性及其成矿元素对前寒武纪基底的继承性表明，构成华南基底和含矿建造的前寒武纪地层（主要为元古界）是华南陆内热液成矿作用的主要成矿物质来源，燕山期花岗岩类是热液成矿作用的主要成矿能量来源；华南热液成矿的区域分布趋势、矿床形成过程和成矿岩体演化等，均表现出与构造热隆起动态有关的成矿特征。多期花岗岩类侵入和迅速块断隆升造成地温梯度增高，基底含矿建造提供成矿物质，以及有利的热液通道和扩容空间是造成构造隆起带或盆地“凹中隆”成矿的重要条件。燕山期花岗岩成岩成矿与大陆地壳的多旋回熔融或再循环有密切的成因关系；地震层析图像资料显示，华南中生代软流圈上涌是造成华南陆壳热隆起的动力学因素。但其成因不同于地幔柱机制，具有被动上涌特征，可能与太平洋板块俯冲形成的大型冷幔柱下沉和地幔过渡带崩溃有关。

Metallogenetic Characteristics of the Important Deposits in South China

The important hydrothermal deposits in South China are characterized by their exploding ore-formation process,continental-scale zoning in mineralization,and the ore-formation materials inherited from the Precambrian basement.These peculiarities should indicate that the source of ore-forming materials came from the Precambrian,mostly from the Proterozoic,as ore-forming formations in which the related metal elements were primitively enriched,and the source of ore-forming energy were derived from the Yanshanian granitic magma.A series of phenomena such as regional distribution,mineralizing process of the deposits,and evolution of the related granite shows that nearly all important hydrothermal deposits in South China were formed in a regionally hot-uplift tectonic setting.Increasing geothermal gradient caused by multiphase felsic magma inputs and rapid block-faulted uplift,supply for ore-bearing materials from the bear formations in basement,and favorable fluid channels and dilation sites are conditions to form the deposits in the tectonic hot-uplift zone and those domes in the Hercynian-Indosinian depression basin.The presented data suggest that both prtrogenesis and metallogenesis of the Yanshanian granite may have a close relationship with multiphase melting and recycled ore-forming materials from the Proterozoic basement.According to the data from seismic tomography,the mantle upwelling breaking through the aquiferous transitional zone appears to be the main dynamic factor controlling of the hot-uplift event in South China during the Mesozoic.It may be a passive mantle upwelling driven by sinking of a giant "cool plume" caused by Pacific plate subduction,rather than thermally driven active mantle upwelling like the mantle plume.