The Study Of Sequence Stratigraphy And Depositional Facies Of Silurian In The Tarim Basin

The study area of this paper is the Tarim Basin,and the target layer is Silurian Formation.The author combines the study of the biostratum,sequence stratigraphy,sedimentary facies and reservoir at home and abroad,directes by the theory of sequence stratigraphy,which combines well drilling,well logging and the analysis of seismic,divides the sequence and tract of the single well,and then compares the profile.After that,the framework of the sequence stratigraphy is built up,and the author researches the plane distributes of the sedimentary facies with the system tract as the equitime unit and confirms the major control factor and the evolution of the sequence.Then researches the relationships between Sequenceand the combination of reservoir,Get the distribution of reservoir sand.Above all the analysis results,combined with hydrocarbon accumulation,predict the favorable reservoir in the study area zone.Have a major impact on the Silurian of Tarim basin tectonic movement is caledonian middle tectonic movement,caledonian adwanced tectonic movement and hercynian early tectonic movement.Comprehensive analysis of previous rock stratum,biostratigraphic and seismic stratigraphy results,according to ancient fossil materials,paleomagnetic data,the distribution layer and the distribution range of the bituminous sandstone,prove that the yimugantawu formation is the Devonian strata and Identifyi that the Silurian,Devonian stratigraphic scheme.Integrated sequence and sedimentary,combined with the evaluation of oil and gas shows and previous research,analysis and study of reservoir characteristics,that there are 3 sets of sequence-related reservoir seal assemblage:(1)composed of SQ1-TST-HST(Kepingtage group lower segmen)sand ping-mixed ping sandstone(reservoir)--SQ2-TST(Kepingtage group medium segment)shelf mudstone(seal)composition;(2)composed of SQ2-HST(Kepingtage group upper segment)sand ping-mixed ping sandstone(reservoir)--SQ3-TST(Tataaiertage group lower segment)mud ping-mixed ping mudstone,and siltstone(seal)composition;(3)composed of SQ3-HST(Tataaiertage group upper segment)sand ping-mixed ping,and Delta sandstone(reservoir)Yimugantawu Group Ping-mixed group mudstone(seal).