安徽滁州李集—三合集地区绢云母矿床地质特征及成矿模式
Geological characteristics and mineralization model of sericite ore deposits in the Liji-Sanheji area, Chuzhou, Anhui Province
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摘要: 皖东滁州张八岭地区具有丰富的绢云母矿产资源,近年来陆续发现并探明多处绢云母矿床,是我国重要的绢云母矿产地。文章基于对安徽滁州李集—三合集一带1:50 000区域矿产地质调查,结合前人资料,论述了该区绢云母矿床的区域地质背景、矿床地质特征、矿床成因及成矿控制因素,建立了绢云母矿床区域成矿模式。研究认为该区绢云母矿床受青白口纪西冷岩组地层控制,西冷岩组原岩为一套海相喷发的火山岩夹陆源碎屑岩,属细碧—石英角斑岩—碎屑岩建造,经低绿片岩相变质变形后形成不同类型的绢云母片岩。该绢云母矿床的成因为火山沉积变质矿床,印支期是西冷岩组变质变形的主构造期,为绢云母矿床的主成矿期。Abstract: The Zhangbaling area in Chuzhou of Anhui Province is endowed with abundant sericite deposits. Discovery of a number of sericite deposits during the past few years made the area an important producing area for sericite resources in China. In combination with previous data available and 1:50 000 regional geological survey in the Liji-Sanheji area, in this paper, we summarize regional geological background, deposit characteristics and genesis, and ore-forming controlling factors to establish a regional metallogenic model of the sercite deposits. The study shows that the deposit is controlled by strata of the Xilengyan Formation in Qingbaihou Period, the protolith of which was one set of marine volcano rocks intercalated with terrigenous clastic rocks, which belong to spilite-quartz keratophyre formation, i.e. sericite schist resulted from low-degree greenschist facies metamorphism. Genesis of sericite deposits in the area belongs to volcano-sedimentary metamorphism and the main mineralization occurred in Indosinian period, which is also the main stage of metamorphism and defomation of the Xilengyan Formation.