In Guantao Formation of Oilfield C in Bohai sea is developed braided river sedimentation and drilling has revealed its potential oil-gas resources.In order to understand the stacking pattern and sedi-mentary evolution model of sand bodies in the Guantao Formation,and identify macroscopic sedimentary control factors,this article uses data of logging,drilling,and modern research to study sedimentary char-acteristics,sand body distribution patterns,and sedimentary control factors.In the Guantao Formation are developed sedimentary microfacies,such as central bank,braided channel,and flood plain sedimenta-tion.In the central bank and braided channel microfacies occur separate sand body,contact,shear,and multi-stage superimposed sand bodies.The distribution pattern of sand bodies is controlled by cycle of reference planes.In middle period of the cycle tend to develop large areal contiguous sand bodies at middle to lower parts of the upward half cycle and longitudinally the sand bodies occur in assembled plates.How-ever,in the downward half cycle is often formed independent sand bodies.The single-staged central bank sedimentation is approximately 62～467 m wide,269～1896 m long.A single channel is approximately 20～151 m wide.The evolution of the braided river is jointly controlled by the ancient source,paleotec-tonic background,and paleoclimate evolution.According to different paleoenvironmental backgrounds are built two sedimentary models of the braided river.Results of this article are of great significance for geo-logical modeling of reservoir and improving the hit rate of sand bodies in development wells.
Guantao Formationbraided riversedimentary characteristicspaleoclimatesedimentary modelOilfield C in Bohai sea
万方数据
维普
