Mixed Sedimentary Characteristics and Pattern of the Fan Delta in the Middle Permian Taerlanggou Profile,Xinjiang Province

Key words: 
• Taerlanggou profile /
• Middle Permian /
• Daheyan Formation /
• Taerlang Formation /
• fan delta /
• mixed sedimentation /
• mixed sedimentary model

Abstract: Based on careful measurement and detailed observation of the Permian outcrop of the Taerlanggou profile in Xinjiang province,the mixed sedimentary characteristics of the land debris and carbonate components in the delta facies of Permian Daheyan Formation and Taerlang Formation were systematically studied. Daheyan Formation consists mainly of fan delta plain distributary channel sediments. At its base it is mainly brownish-red medium conglomerate with coarse gravel,and carbonate components are rarely found. At the top it is mainly brownish-red fine conglomerate and medium gravel,mixed with many gravelly micrite bands. The Taerlang Formation was a fan delta front underwater distributary channel and underwater bay between the channels from the base bottom upwards. The underwater distributary channel,a glutenite convex at the bottom and flat-topped,developed a grayish-green fine conglomerate with medium gravel and gravelly micrite in discontinuous bands of short extent at the bottom,but extending a long distance horizontally at the top. The underwater bay between the distributary channels mainly developed a grayishgreen mudstone and layered sandy micrite distributed evenly in all horizontal directions. In combination with previous studies of the Middle Permian paleoclimate,sedimentary environment and other aspects of the study area,the mixed sedimentary model of the fan delta was established.