金矿床密集区形成的基本条件—以华北地台为例

金矿床密集区受含金丰度高的岩石圈地幔区控制和制约。本文以华北地台若干金矿床密集区为例，从地壳演化的角度，初步探索了初始地壳的含金丰度变化与金矿床密集区的关系。文章认为，初始地壳只有经活化改造和活化再造，才能形成金元素的富集域或金矿床密集区。金矿床密集区的形成是矿源、热源、搬运介质和构造条件的统一体。其中，前寒武纪古老变质基底是金矿形成的物质基础，变质基底双层结构的下层结构是金矿床的主要赋存部位，岩浆一热构造作用是初始地壳内成矿物质活化的动力，岩浆活动、流体运移是矿质的搬运工具，构造断裂是含矿热液运移的通道和聚集的空间，特别是深断裂能使深源成矿物质迁移至地壳，使矿质来源更加丰富。

THE BASIC CONDITION FORMATION OF THE GOLD MINE CONCENTRATED AREA-Example by the North China platform

This paper take a certain nurnber of examples, on the view of the lithospherEvolution, studying the relathahip between the gold conent in the original crust and the goldInine conentrated area of the North China platforms. It is thought that the original crust is oulytransformed through the reforming actbotbo and rebuilding acthatdri, and can form the goldelernent enrich area and /or gold mine colcentrated area. The formaion of the gold mineconcentrated area is the unify system of mneral origin, hydrotharrna source, cnying mediumand the conditdri of structure. Among them, the metamorphose baseInent of Precamrian is thebase of gold-ore formation- The lower level structure of the double-deck structure ofmetamorphose basement is the rnaor POSition of gold mineralization. The Inagrnahydrothermalprocess is the force of ore-forming substance activation inside the original crust. Magma activityand hydrothermal rnovemt are the tool for canying orefondng substance, Fault structure zoneis the charmel and the space for the auriferous hydrothermal moving and gathering- Especially,deep fault fracture could rnake the deep ore - fodring substance to move to crust. bely faultrnakes the nature gold source richer.