胶西北金矿集中区亚热柱幔枝构造成矿研究

Study on Sub-mantle Plume-Mantle Branch Structures in Gold Ore-concentrated Areas in Northwest Shandong Peninsula

摘要:

胶西北是我国最大的黄金矿集区，不仅黄金储量巨大，而且成矿时间集中（115±5)Ma。研究认为燕山运动以来，华北东部地区进入了地幔热柱演化阶段;胶西北形成了莱阳地幔亚热柱及其外围郭家店、艾山、盘石店等幔枝构造体系。深源含矿流体通过地幔热柱→地幔亚热柱→幔枝构造→有利构造扩容带，迁移到幔枝构造的脆韧性韧脆性剪切带、侵入岩体的内、外接触带、密集的构造裂隙带、各种脉岩与围岩的接触带等有利部位集聚成矿，从而构成以幔枝构造为中心的金成矿密集区。该文以郭家店幔枝构造研究为例，分析了成矿作用，归纳了成矿模式。

Abstract:

Northwest Shandong peninsula area is the largest gold ore concentration area in China. It has huge reserves, and ore-forming time is concentrated in 115±5Ma. It is show that since the Yanshan movement, eastern part of North China has come into the mantle plume evolution stage. Laiyang sub-mantle plume has been formed in northwest area, while Guojiadian, Aishan and Panshidian mantle branch structures have been formed in its peripheral areas. The ore-bearing fluid in deep-derived was migrated to favorable zones and formed gold resources, such as ductile-brattle or brattle-ductile zones, internal or external contact zones of intrusives, dense structural fractures, contact zones between dykes and country rocks through mantle plumes to sub-mantle plume and mantle branch structures, and formed gold ore concentrated area with mantle branch structure at the center. In this paper, setting Guojiadian mantle branch structure as an example, mineralization has been analyzed, and metallogenic model has been set up.