赣北主要内生金矿床的形成条件

赣北地区的金矿床,可分为含金韧性剪切带型、硅化破碎带型、隐爆角砾岩型和微细粒浸染型等4个类型,其原始成矿物质来源于上地幔,通过火山喷发—沉积作用,形成含金沉积建造和含金火山岩建造.钠、钾质两个系列的花岗质岩石都可以形成金矿床.矿化富集主要通过韧、脆性变形和岩浆隐蔽爆破,产生多次破碎,多期蚀变矿化.在中—低温热液阶段,含矿热液体系的HS~-、Cl~-离子减少,还原介质增加的条件下沉淀富集,形成不同类型的金矿床.

ORE-FORMING CONDITIONS OF THE MAIN GOLD ENDOGENETIC DEPOSITS IN NORTHERN JIANGXI PROVINCE

The gold deposits in Northern Jiangxi might be grouped into four types:ductile shear belt type,silicified broken breccia belt type,hidden explosive breccia type and microscopic disseminated type. The original metallogenic materials of gold came from the upper mantle. Au-bearing sedimentary formation and volcanic rock series were come from volcanic explosion and sedimentation process. The gold ore deposits might occur in both natro and patassic granitic rock series. The ore concentration are controlled by ductile and brittle deformation ,and mag-matic hidden explosion resulting in rock multiple breaking and multiphase alteration. Under moderate-low temperature condition,the gold was deposited from Au-bearing hydrothermal system with the decrease of HS-.C1-concentration and the increase of reducing media and thus various types of gold deposits were generated.