Quartz sandstone

lithic quartz sandstone and lithic sandstone are main types of reservoir rock in Shan Member-Ⅰ

Ⅱ of Shanxi Formation and He Member-Ⅷ of Shihezi Formation in the Permian in Suligemiao region. Those rocks

with good maturation in composition and moderate maturation in texture

have experienced diagenesis of compaction

cementation and dissolution and have formed secondary solution pore

primary residual inter-granular pore space and intercrystalline pore. Reservoir in the region can be divided into four types on the basis of its physical property

capillary pressure curves and relations of pore combination. It is discovered by studying that braided and meandering stream channel sand bars

delta plain branch channels and underwater branch channels in braided and meandering stream delta front are favorite reservoir belts in this region

which control the distribution of highly permeable reservoir. The well graded quartz sandstone with high content of quartz and coarse quartz is the foundation for forming good reservoir. The development of secondary pore is the key for forming highly permeable reservoir.