These rocks are lack of foliation and resulted from the brittle fragmentation of mineral grains with rotation of grain fragments accompanied by fractional grain boundary sliding and dilatancy .

• 这类岩石缺乏面理构造，是由于矿物颗粒的脆性碎裂，旋转以及颗粒边界的磨擦滑动和扩展而造成的。