In the northwestern area of Sichuan such as Qingyanggou section and Guanyinya section in Hanwang and Jushui section in Anxian,the Ma' antang siliceous sponge reefs in the Upper Triassic Carnian, whose subfacies can be divided into reef base,reef core,reef flank and inter-reef deposits etc.,mainly appear in carbonate ramp slopes. And the lithofacies and community characteristics can be determined on the basis of the concentration of intraclasts,taphonomy characteristics and the ratio of marls in siliceous sponge reefs. Reef limestones usually include a sponge framework rock and calcareous microbialite clotted limestone,and accessory reef organisms mainly involves foraminifera, bivalves, echinoderms and ostracodes, brachiopods, dasycladales and calcareous sponge etc. After the extinction of siliceous sponge reefs in Ma' antang, the overlying black shales were deposited. Carnian extreme climate events in Triassic have exerted an extensive influence on the global biosphere, which means that the global sea-level fluctuation rate in Upper Triassic Carnian that is higher than the growth rate of sponge reefs,coupled with the frequent plate tectonics during this period, the concentrated outbreak in fire rock provinces and prevalence of monsoon climate, led to the extinction of siliceous sponge reefs.