Sedimentary Facies Analysis Of Biegentawu Formation Of The Upper Carboniferous In Kake Area,Xinjiang Autonomous Region

The present paper consists mainly of 6 parts.1.The carbonate was identified 9 kinds of major carbonate rocks: mudstone,bioclastiferous mudstone,clastizoic mudstone,bioclastiferous pelletoid limestone,sparry clastizoic limestone,clastizoic rudstone,sandy rudstone,bioclastiferous sandy limestone and sandy sparite.2.The terrestrial clastic rock was recognized 10 kinds of major types: conglomerate,pebbly calcareous sandstone,calcareous gritstone,quartz medium-sandstone,calcareous medium-sandstone,quartz packsand,calcareous packsand,calcareous siltstone,argillaceous siltstone and calcareous mudstone.3.Five types of lithological combinations can be identified in the formation.Combination 1-1: The down unit is mainly laminated calcareous sandstone or sandy limestone.The upper unit is mostly calcareous mudstone.Combination 1-2: The lower unit,largely dark gray sandy rudstone and the overlying unit is primarily offwhite medium-layer sandy sparite.Combination 2-1: The underpart is basically bioclastiferous pelletoid limestone and the upside is usually quartz sandstone.Combination 2-2: The substratum is generally calcareous mudstone,the upper layer is grey black laminated clastizoic mudstone or bioclastiferous pelletoid limestone.Combination 3-1: Dark gray thin-layer clastizoic mudstone lies on top of mudstone.4.It can be divided into four sedimentary facies in the Biegentawu Formation: barrier coast facies,open platform facies,platform margin facies and platform margin slope facies.Six subfacies: tidal flat,tidal channel,lagoon,platform-margin shoal,upslope and downslope.Eleven microfacies.5.Sedimentary facies models of the Biegentawu Formation have been built up in the study area: barrier coast model and platform-gentle slope model.