The Evolutionary Characteristics of Lower Permian Keziliqiman Reefs in the Southwest Margin of Tarim Basin, Northwest China

Figure 3

Types of reef limestone in Keziliqiman Formation. (a) Packstone in the reef base, with echinoderms as the main bioclastic type. (b) Colospongia bafflestone in the reef core, with most of the sponges dolomitized. (c) Coral framestone in the upper zone of the reef core, with colonial Tetracoralla visible. (d) Ash black micrite in the back reef, with good stratification. (e) Bioclastic grainstone in the front reef, with dissolution pores visible. (f) Micritic-powdery dolomite in the reef cap.

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