Keywords: 
• Garbonate rock /
• Fractures /
• Pores typoe

Abstract: The carbonate of Lower Permain in south Sichuan is typical fractures storage .and it in-eludes many types pores and fractures. No doubt fractures caused by structure activities take an important part in gas traps,but some other types of secondary pores and fractures are very significant too. Pried on the analysis of sediments and diagenesis of lower Permain series (slices aid cores of Weh Yang 52,Si 18 and Lai 4;sections of Gusong,Xinwen and Hongqiao in south Sichuan,the authors studied systematically all types of pores and f racturcs including structure Sichuan),the authors studied systemetically all types of pores and fractures including structure fissurcs,secondary corrosion cavities,cantract pores and crevices, unlaaded f lssures,regionah rifts, crush cracks (mcchanical,hydralic and oil一gas divulsional),separate fissures in layers,collapse brcccias clinks and seaming lines, etc.lay researching thcir mechanism and signif iw cance to fractures system,the gores ( general) causal classification of Lower Permain Series was presented,Although so many types pores exist,the gas reservior constructures in south Sichuan were formed in Xishan Activeity Period,so the combination of fractures by structures and cor-rusion cavities by structural period karstification and other pores formed in the same period is most important.