黔西南泥堡金矿床滑坡堆积型矿体成矿作用探讨

Disscussion on the Metallogenesis of Landslide Accumulation Type Au Orebodies in the Nibao Gold Deposit Southwest Guizhou,China

二龙抢宝背斜隆升导致F_4断层上盘岩块在重力作用下向北滑坡,泥堡氧化矿体几乎都限制在滑坡体中。因而滑坡堆积是氧化矿体的主要成矿机制。原生矿石在滑坡时与围岩混合造成矿石贫化,但混合矿石同时发生碎裂和扩容作用,增大其孔隙度和渗透性,在表生作用环境下载金含砷矿物得以部分分解而成为易选冶氧化矿石,深入研究滑坡堆积过程的氧化机制有利于提高该类矿床黄金资源利用率和地质勘探程度。

A recent synthetically study on the oxidized ore of Nibao gold deposit has revealed that the deposit forming factor is landslide-accumulation. The oxidized ores restricted in the landslide, resulted from the gravity collapse northwards of the hanging wall of F4 fault because of the uplift of Erlongqiangbao anticline. The ore dilution occurs in mixing up the ore with the wall rock during the collapse. However, the mixed ores were cracked and expanded; its porosity and permeability increased, becoming the easily dressing-smelting ores by the decomposition of gold-bearing arsenic minerals in supergene environment. All these oxidized ores belong to the type of landslide- accumulation. Researching on the landslide-accumulation orebody particularity may increase the utilization of gold resources and its exploration degree.