Controlling effect of lithofacies on reservoirs of Baikouquan formation in Mabei area

This paper focuses on the reservoir of Triassic Baikouquan formation in Mabei area of Junggar basin and aims to find out the controlling effect of lithofacies developed in different sedimentary microfacies on reservoir property.Based on core observation,thin section authentication,well logging,mud logging and physical property analysis,combined with the depositional setting and tectonic environment of the study area,the main lithofacies developed in different fan-delta sedimentary microfacies were classified with the emphasis on the sedimentary microfacies and lithology juxtaposition;moreover,the physical property and the controlling effect on reservoir property of different lithofacies were also analyzed.The results show that underwater channel glutenite facies,estuary dam and distal sandbar sandstone facies are much more favorable reservoir facies than braided channel glutenite facies,subaqueous main channel conglomerate facies,end of underwater channel sandstone facies and superaqueous mudslides conglomerate facies.Subaqueous mudslides glutenite facies and frontal fan-delta siltstone faciesare potential reservoir facies.Subaqueous interchannel sand-mudstone facies,plain interchannel sand-mudstone facies,frontal fan-delta mudstone facies almost have no reservoir property.At last,on the basis of sedimentary facies and lithofacies research,favorable reservoir development area in Mabei was predicted.