Fracture, Dissolution, and Cementation Events in Ordovician Carbonate Reservoirs, Tarim Basin, NW China

Figure 4

Photomicrographs of Ordovician carbonates. (a) Plane light optical photomicrograph of the Yijianfang Formation, (b) Tumuxiuke Formation, and (c) Lianglitage Formation host rocks. IP = interparticle pores; IX = intercrystalline pores. (d) Optical-CL photomicrograph of grainstone cemented by fibrous to bladed calcite rims (Cc0a) and drusy mosaic (Cc0b) cements. (e) Optical-CL photomicrograph of grainstone cemented by syntaxial cement (Cc0c). (f) Hand specimen of the karstic horizon within the Lianglitage Formation showing matrix-rich, clast-supported chaotic breccia. (g) Plane light optical photomicrograph of angular red clasts in Lianglitage Formation breccias. (h) Close-up photomicrograph of the breccia matrix.

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