滇西大平掌铜矿凝灰岩的特性及防塌研究  

Characteristics and anti-collapse of tuff in Dapingzhang Copper Mine in Western Yunnan

作　　者：郑明雄 李保珠[2] Zheng Mingxiong;Li Baozhu(Computing Center of Kunming University of Science and Technology,Kunming 650031,China;College of Land and Resources of Kunming University of Science and Technology,Kunming 650031,China)

机构地区：[1]昆明理工大学计算中心,昆明650031 [2]昆明理工大学国土资源工程学院,昆明650031

出　　处：《工程勘察》2020年第7期6-11,共6页Geotechnical Investigation & Surveying

基　　金：国家自然科学基金项目(51664026)。

摘　　要：凝灰岩遇水软弱化及快速分解带来很多问题。本文通过XRF、XRD、SEM、TEM、ICP-MS及化学试验等方法,研究了滇西大平掌铜矿高风化软弱凝灰岩的成分、微观结构、离子溶出及防塌钻井液配方等内容,通过这些研究,可认知凝灰岩快速软化分解的机理,并为工程应用提供参考。研究表明:大平掌凝灰岩中石英、伊利石、白云母和黄铁矿共占90%以上,伊利石和白云母等硅酸盐是快速分解的矿物因素。微片层结构是凝灰岩中最普遍和典型的结构形态,该结构是具有强吸水性硅酸盐矿物的典型结构,有利于水在凝灰岩中快速运移并形成孔隙,高分解性凝灰岩普遍具有该微观形态。凝灰岩内的黄铁矿氧化生成硫酸和硫酸盐,ICP-MS测试表明,凝灰岩在水中快速分解时溶出较多金属离子,离子溶出对凝灰岩分解起促进作用。在前期研究的基础上,通过防塌钻井液试验,获得了具有较好防塌能力的钻井液配方。The softening and rapid decomposition of tuff brings about many problems. XRF,XRD,SEM,TEM,ICP-MS and chemical experiments were used to study the composition, microstructure, ion dissolution and anti-collapse drilling fluid ingredient of the highly weathered soft tuff in the Dapingzhang Copper Mine in Western Yunnan Province,China in this paper. The study could help to perceive the mechanism of rapid soften and decomposition of tuff and provide a reference for engineering applications.The study shows that the total content of quartz,illite,muscovite and pyrite in Dapingzhang tuff is more than 90%,and silicates such as illite and muscovite are the rapid decomposition mineral. The microflake layer structure is the most common form of tuff,and this structure is the typical structure of strong waterabsorption silicate minerals. The high-decomposing tuff generally has this microscopic shape,which is beneficial for water migration and pore forming in tuff. The pyrite in the tuff is oxidized to produce sulfuric acid and sulfate. The ICP-MS test shows that many metal ions are dissolved when tuff is decomposed rapidly in water,and the ion dissolution promotes the decomposition of tuff. Based on the previous study,through anti-collapse drilling fluid experiment,the anti-collapse drilling fluid formulation was obtained.

关 键 词：大平掌铜矿 凝灰岩 高分解性 特性 防塌 

分 类 号：P585[天文地球—岩石学]