澜沧铅矿凝灰岩膨胀性微观分析研究

Study on Swelling Property of Tuff in Lancang Lead Ore by Micro-analysis

凝灰岩属于膨胀岩中的一种,它具有很强的膨胀崩解性。以云南澜沧铅矿的凝灰岩为例,通过微观分析,研究了解澜沧铅矿的凝灰岩主要矿物成分和矿物的微观晶体变化。研究结果表明,澜沧铅矿凝灰岩中导致膨胀的主要粘土矿物是蒙脱石,且含有不膨胀的粘土矿物绿泥石,不含有高岭石和伊利石。凝灰岩膨胀的根本原因是蒙脱石晶体的晶面间距变大产生的。

Tuff is a kind of swelling rock being of swell and collapse. Taking the tuff in Lancang Lead Ore in Yunnan as the example, the main mineral composition and its micro crystal change of the tuff are studied by micro-analysis. The result shows that in the tuff therein, the main clay mineral leading to swell is montmorillonite, and kaolinite and ledikite are not contained but a non-swelling clay mineral, chlorite, is contained. The basic reason of tuff swelling is increased interplanar distance of montmorillonite crystal.