云南小湾断层泥中伊利石矿物特征及其意义

CHAKACTERISTICS OF ILLITE MINERALS IN FAULT GOUGE FROM XIAOWAN,YUNNAN AND THEIR GEOLOGICAL SIGNFICANCE

根据扫描电镜观察、Ｘ射线衍射和化学分析，研究断层泥中伊利石矿物的特征。研究表明，小湾断层泥中伊利石属Ｉ＋ＩＳＩＩ结构，膨胀层约占１５％，ＩＭ多型，层间阳离子２Ｃａ＋Ｎａ＋Ｋ≈１，伊利石的ｂ。值等于８．９９３Ａ，这些参数反映了小湾断层活动的机制为低压、低温（＜２００℃）。

In this paper，characteristics of illite in fault gouges are studied by SEM, XRD and chemicalanalysis.The study shows that illite belongs to I ＋ISIl structure；expansibility takes approxi-mately 15％； IMis of multiple paterns interlayer positive ions 2Ca＋Na＋K≈l；b_0 value of illite is8．993 in fault gouge at Xiaowan，which show that mechanisms of fault movement in Xiaowanare of low pressure and temperature（＜200℃）。