It was shown by field investigation and lab tests that the types of altered rocks were mostly those of montmorillonitization, and the altered clay mineral was mainly pure montmorillanite, which rendered the altered rock both soft and expansive.
It was shown by field investigation and lab tests that the types of altered rocks were mostly those of montmorillonitization, and the altered clay mineral was mainly pure montmorillanite, which rendered the altered rock both soft and expansive.
野外地质调查和室内测试表明：滇藏铁路滇西北段出露的多为蒙脱石化蚀变岩带，蚀变岩的黏土矿物组成绝大多数都是单矿物的蒙脱石，导致该地区的蚀变岩既是强度极低的软岩，又是典型的膨胀岩。