Study On Logging Interpretation Technology Of Chang 8 Reservoir In Jingan Area

The exploration practice in recent years shows that the study of low permeability and ultra low permeability reservoirs is becoming more and more important,which can promote the development of petroleum industry in China.Chang 8 reservoir in Jingan area is of low porosity and low permeability because of its poor physical properties.This paper studies the study area from four aspects:reservoir characteristics,logging selection and logging data preprocessing,log data interpretation and productivity identification.?1?The rock types of Chang 8 reservoir in Jingan area are mainly feldspathic sandstone and lithic sandstone.The pore type is mainly intergranular pore and feldspar solution pore,pore structure is mainly small pore,fine throat type,reservoir physical property is poor,belongs to low porosity and low permeability reservoir.?2?The optimum selection of logging data shows that natural gamma log curve,compensated neutron log curve and array induction log curve are more sensitive to lithology and reservoir fluid properties than other curves of the same series.By analyzing the salinity of formation water,it is found that the salinity of the whole formation water of reservoir is small,and only a few wells have high values,so there is no need for zoning calculation.?3?The mud content interpretation model,porosity interpretation model,permeability interpretation model and water saturation interpretation model are established,and the accuracy of the model is high.Intrusion analysis method,differential analysis method and chart analysis method have been used to identify the reservoirs of Chang 8 reservoir,and good results have been obtained.?4?Productivity prediction of reservoir is carried out by using productivity coefficient method and comprehensive index method.It is found that the main productivity zone of Chang8 reservoir is mainly Chang81 region and Chang82 part area vertically,while the main productivity area of Chang82 reservoir is mainly concentrated in the central region and the main productivity area of Chang8₁ reservoir is mainly concentrated in the southeast region.