Research On Sedimentary Facies And Reservoir Of Lower Es₃- Upper Es₄ Of Li 38 Block In Dongying Depression

With the deepening of oil and gas exploration degree, the proportion of low permeability reservoir in oil and gas resources development becomes larger and larger. Comprehensively using seismic, logging, core analysis and test data, integrating multidisciplinary, adopting a variety of techniques, the study of low permeable reservoir’s sedimentary facies and characteristics in Li 38 Block of Shanjia-Temple Oilfield is completed, and obtained some achievements and recognition.The study referred sedimentology, sequence stratigraphy and reservoir geology theory as a guide. Comprehensively using well drilling, logging, core analysis and test data, completed fine stratigraphy comparison. The thickness of target strata is variable and becomes larger from west to east. Referencing regional depositional environment, combining with the signs of sediment facies, determined the stratigraphy of lower Es3- upper Es4 mainly developing inshore subaqueous fan, further divided the sedimentary microfacies. On the basis of the distribution law of the sedimentary microfacies, established sedimentary facies model and summarized the evolution law of sedimentary facies. The inshore subaqueous fan is a set of retrograding sequence from the bottom up.Based on the micro experiment data, the type of sandstone reservoir is mainly feldspar sandstone and lithic sandstone with medium maturity. Reservoir space mainly includes intergranular pore and dissolution pore. And reservoir can be divided into three categories according to the pore structure.On the basis of studying on the "four property", reservoir property prediction model was established. According to the prediction of reservoir physical property, concluded medium pore- low permeability and low pore- super low permeability reservoirs were main reservoir of the researching zone. Based on the calculation of reservoir heterogeneity parameters, the paper studied reservoir’s intrabed, interbed and planar heterogeneity, analyzed the property characteristics. The study came out that the intrabed and interbed heterogeneities were serious, and the heterogeneity of sand body in braided channel is severer than that in inter channel, the homogeneity in middle-fan front is relatively good.On the basis of comprehensive analyzing of factors which affected the quality of reservoir, optimizing reservoir evaluation parameters, reservoir comprehensive evaluation model was set up. The study completed the objective interval’s comprehensive geological evaluation, classified reservoir as 4 types in the light of evaluation result, and type I and II reservoirs are favorable. Combining with dynamic and static data, the paper finally implemented the favorable oil-containing zone and put forward the location of optimizing roll prospecting target.