Research On The Reservoir Characteristics Of The Upper8-middle2 Sandbody Of Es3 Section In The Northeast Flank Of Qiaokou

The northeast flank of Qiaokou is one of the potential regions in Qiaokou oil field for scrolling expansion and improving resources. Affected by the deposition, structure and other factors, layers changed a lot. Most of the previous studies were on the deep layers. As the main oil-bearing in shallow layers, reservoir characteristics of the Upper 8-Middle 2 sandbody of Es3 section have not studied till now.On the basis of previous research results, applied with the theory of reservoir sedimentology, petroleum geology, geophysics and geophysical logging interpretation, combined with core description, thin section analysis, scanning electron microscope, logging, test data and other analytic machinery, the reservoir characteristic are studied deeply in this paper.Here divide the Upper 8-Middle 2 sandbody of Es3 section into 27 small layers. 8 small layers are selected in this study with larger sandstone thickness.The direction of provenance is in NE and SW by a comprehensive analysis of heavy minerals, ancient water and compositional maturity of sandstone. On this basis, summarizing the sedimentary facies marks and logging curve shape, it is thought that the front-delta including three types sedimentary microfacies: the underwater distributary channel, the flank of underwater distributary channel and the far sand dam, the sandstones in the underwater distributary channel is the most advantageous sandbody.The lithology is litharenite feldspathie sandstone in the northeast flank of Qiaokou. Diameter of the particles between 0.05 mm to 0.25 mm, sorting is fine-medium. The type of the pore in the reservoirs mainly primary porosity pores and secondary intergranular dissolved pores. The average porosity value is 10.68%, the average porosity value is 4.33 mD in the reservoirs, which have low porosity and special low permeability. We can conclude that the diagenesis are mainly mechanical compaction and pressure solution, cementation, metasomatic alteration, dissolution. The research area belongs to the mesozone rock A stage.By the comprehensive analysis of logging data, core data and well test data, we can summarize the effective low limit of reservoir parameters of the Upper 8-Middle 2 sandbody of Es3 section in the research area. In light of reservoir evaluation, the reservoirs can be classified into three types.The reservoir coefficient in Q43-1 flank can be described as type-â… and Q58 flank can be described as type-â…¡.