辽宁省金矿集中区及其与构造样式的关系

AURIFEROUS PROVINCES AND THEIR RELATIONS TO TECTONIC STYLES IN THE LIAONlNG PROVINCE

本文将辽宁省金矿划分四种类型,十个主要金矿集中区。这些集中区均受华北地台东西向基底构造活动带及中生代太平洋板块俯冲影响、所产生的北西向构造挤压带和北东向构造—岩浆岩带的复合作用控制。它们分别处于太不洋成矿带的内带(辽东)和外带(辽西)。并以郯庐断裂为轴线,构成了两大“U”字形,类似共轭曲线展布的构造样式。根据深部地球物理资料,综合分析了控制金矿集中区构造样式的形成机制。区内脉状金矿大都分布在深断裂(深度大于五公里断裂)带附近。

Tectonically, the Liaoning Province is situated in the northern part of the North China Platform. It makes up the eastern end of a gold-polymetal metallo-genie belt that constitutes part of the Pacific metallogenic belt.The gold deposits in the Liaoning Province are classified into four types in this paper: a) the Mesozoic volcanic-bubvolcanic hydrothermal type; b) the Me-sozoic altered and fractured quartz lodes; c) the Mesozoic Maoling altered rock type and d)the Archean Longwangmiao greenstone type. The above four types of gold deposits are concentrated in ten auriferous provinces in the Liaoning Province. These auriferous provinces are strictly controlled by the long active EW trending basement structures, the regional NW-SE trending compressive structures and the Mesozoic NE to NNE trending structural-magmatic zones. The auriferous provinces are usually located at the intersections of these structures. These auriferous provinces comprise two 'U' shaped patterns in the western and southern Liaoning Province respectively, somewhat similar to two conjugate images. The'U' pattern in the southern Liaoning Province was controlled by the contact line between the eugeosyncline and miogeosyncline of the Early Proterozoic aulacogen-the so-called'M-Z'line, e.g., it is controlled by the basement structural active zone) whereas the 'U' pattern in the western Liaoning Province was controlled by the marginal fractures of the Mesozoic volcanic basin,The famous Tanlu Fracture zone serves as the axis of the two conjugate 'U'patterns.Deep geophysical data suggest that the tectonic style of the Liaoning Province had been closely related to the formation-accreation-remobization events of the Sino-Korean platform. Most of the gold lodes in the region are located adjacent to deep fractures(depths greater than 5 km).