A reef situated 500m southesast of Keziliqiman

Pishal County

Xinjiang belongs to theKeziliqiman Formation of the Lower Permian. The reef core is 57.6m thick and its maximumexposure is up to 300m across. The reef flank

consisting of grain limestone

middle to thinbedded marly limestbne and bioclactic limestone

is connected with the reef core by interfingering.Reef-building organisms consist chiefly of colonial tetracorals

Sphinctozoas

blue-greenalgae and Tubiphytes and then bryozoans

Inozoas and hydrozoans. Most of the organismshave kept their original growth patterns. The orgamisms could be divided into 4 micro-factessuch as baffle limestone

baffle-skeletal limestone

bound limestone and reef debris limestoneand 4 stages of reef evolution correspondingly based on the vertical zonation.