Middle-Upper Cambrian dolomites in Shimen,Hunan Province,are mainly composed of anhedral micritic dolomite,euhedral and subhedral granular dolomites,grain dolomite.

湖南石门中上寒武统白云岩极其发育,类多样,不同类的白云岩其成因机理和白云石化模式各不相同。