Effectiveness Evaluation And Sweet Spot Prediction Of Well-seismic Combination Of Beach Bar Sand Reservoir

Beach bar sand reservoir is a very important kind of lithologic reservoir,and the proven reserves of beach bar sand reservoir in the Dongying sag are considerable.Beach bar sand reservoir has gradually become the focus of Shengli Oilfield research.However,due to the characteristics of thin single layer,thin interbedded sand and mud,poor reservoir physical properties and fast lateral change,therefore,it has caused certain difficulties in the logging evaluation and sweet spot prediction of beach bar sand reservoirs.According to the characteristics of beach bar sand reservoir,in order to accurately interpret the beach bar sand reservoir,this paper first analyzes the borehole quality of logging data,lithologic depth homing and logging data standardization processing,in order to ensure the reliability of logging data in subsequent interpretation.Based on the analysis of reservoir characteristics,the conventional log interpretation model and the log interpretation model based on the ternary argillaceous and Coates equation are established respectively,which are verified with the core analysis data.The log interpretation model based on the ternary argillaceous and Coates equation is more suitable for the beach bar sand reservoir in the Dongying sag,and the physical properties of the effective reservoir are calculated by sections on the basis of the physical property interpretation The lower limit of dynamic physical properties with depth is established.According to the lower limit of reservoir dynamic physical property,the indicator curve of reservoir sweet spot is established,which is compared with the indicator curve of physical property quality,hydrocarbon bearing quality and pore quality.The results show that the indicator curve of reservoir sweet spot based on the lower limit of reservoir dynamic physical property is more consistent with the well testing data.Based on the division of single well logging productivity sweet spot and the prediction of plane radial flow energy,the quality model of single well logging productivity sweet spot is established,and the single well productivity is characterized by the quality of logging productivity sweet spot.In order to accurately predict the sweet spot of beach bar sand reservoir and reasonably guide the oil and gas exploration,this paper adopts the idea of combining well and seismic to predict the sweet spot of the study area.The first idea is to use the waveform indicating simulation method to compare the waveform indicating impedance curve simulation,waveform indicating natural gamma curve simulation and waveform indicating dessert indicating curve simulation.The results show that the waveform indicating dessert indicating curve simulation can better reflect the dominant reservoir section on the well,and has higher resolution in the vertical direction,and the effective sand body inversed is distributed from the horizontal direction,the continuity is good,and the inversion results can accurately reflect the beach bar sand reservoir profile.The second idea is to use seismic attributes to predict the quality of well productivity sweet spot.After a variety of seismic attributes optimization,support vector machine regression method is used to predict the quality of well productivity sweet spot through sensitive seismic attributes,and to establish the quality plan of well logging productivity sweet spot.And by comparing with the actual production materials,the relationship between the quality plan of the sweet phase of logging productivity and the actual production materials is better.Comparing the prediction results of sweet spots in the study area with the two ideas,the prediction results of the two methods are in good agreement,and there are two favorable areas that have not been drilled in the study area.