论文部分内容阅读
皇城山银矿位于大别山北麓中新生代坳陷南缘。矿体赋存于白垩系陈棚组火山岩及海西早期斜长花岗岩的枝状裂隙中。裂隙向下呈楔状延伸的特征,决定着次火山岩上拱作用下的拉张应力环境。赋矿岩石具强烈的硅质交代结构及假晶洞,假晶腺等构造,指示矿床在漫长的热液交代作用下形成。矿石矿物具典型的低温组合,黄铁矿测试具较高的Co/Ni比值,硫同位素分析结果亦具生物分馏特征,表明热液源于火山岩中的天水淋滤。矿床明显处于银高背景区中的低缓异常中心,反映成矿物质来源于陈棚组地层。近矿(?)岩的线型蚀变与广泛发育的面型蚀变的规律性变化,进一步证明矿床形成于地表水—地热循环系统。诸控矿因素与燕山运动发生有机联系并指示良好的成矿前景。
Huangshan Silver Mine is located in the northern foothills of the Dabie Mountains in the southern Cenozoic Cenozoic. Ore bodies occur in the Cretaceous Chenpeng volcanic rocks and the Hercynian early plagioclase granite in the fissures. The fissure downward wedge-shaped extension determines the tensile stress environment under the arch of subvolcanic rocks. The ore-bearing rocks are strongly composed of siliceous metasomatism structures and pseudocrystals and pseudomorphs, indicating that the deposits formed under the long hydrothermal metasomatism. Typical low-temperature combinations of ore minerals, pyrite test with a higher Co / Ni ratio, sulfur isotope analysis results also have biological fractionation characteristics, indicating that hydrothermal source from volcanic Tianshui leaching. The deposit is obviously located in the center of low and moderate anomalies in the high silver background area, reflecting that the ore-forming material is derived from the Chenpeng Formation. The regular alteration of linear alteration and extensively developed surface alteration of near-ores ()) rocks further prove that the deposit is formed in the surface water-geothermal cycle system. The ore-controlling factors and the Yanshanian movement have an organic connection and indicate a good prospect of mineralization.