Sedimentary facies of the Chang 6_3 reservoir in the Huaqing area of the Ordos Basin

The Chang 63 reservoir in the upper Triassic Yanchang formation is an important exploration target in the Huaqing area,Ordos Basin. The sedimentary facies of the Chang 63 reservoir has been studied meticulously based on core data and log data. It is recognized that the Chang 63 reservoir belongs to delta front sublacustrine slump turbidite fan deposition,which can be further divided into 3 subfacies of inner,middle and outer fans and several microfacies according to sedimentary characteristics. The distributary channel microfacies of the middle fan were most developed,covering 80% of the total turbidite fan area. On this basis,this paper predicts favorable sedimentary microfacies distribution and sedimentation model.