Logging Evaluation Of Complex Lithologic Reservoirs In Wulan Sag

The Wulan sag is a key area for oilfield exploration.The lithology is complex and the reservoirs are mostly low-porosity and low-permeability reservoirs.In this paper,the lithology,physical properties and characteristics of the Wulan sag,the reservoir evaluation parameters and the evaluation methods are difficult to explain,and the multi-source data such as geological logging,gas measurement,testing and oil testing are integrated to evaluate the oil and gas layer,and the depression is systematically analyzed.The log response characteristics of each block were established,and the parameter interpretation model and reservoir evaluation method of the relevant complex oil and gas layers were establishedAiming at the lithologic complex problem in this region,this paper uses natural gamma,three-porosity curves and imaging logging methods to establish various types of formation logging response characteristics for glutenite and igneous rock,and establish porosity and permeability.Computational model;at the same time,for the calculation of the pores,seepage and saturation of these two lithologies,the three-porosity of different lithologies is corrected by taking into account the complex characteristics of lithology;the calculation of porosity by nuclear magnetic logging is improved.The accuracy of calculation of porosity For the calculation of permeability,the main method is to combine the core magnetic magnetic experiment and nuclear magnetic logging data,improve the calculation method and improve the accuracy of the permeabilityIn terms of fluid identification,array induction intrusion features,five-curve overlap,saturation factor method,resistivity increase method,comprehensive determination of total hydrocarbon and logging response,three-water model,and four middle-research are proposed for reservoir characteristics of different blocks.The method of judging the oiliness of igneous rocks provides a basis for quickly and accurately identifying the properties of fluidsBased on the rock physics and core nucleus magnetic experiments,the reservoir pore filling parameter interpretation model is established and improved;the reservoir parameter calculation accuracy is improved,and the nuclear magnetic logging,core magnetic magnetic experiment and other materials are fully utilized,combined with the test oil situation,and analyzed.The characteristics of reservoir pore structure,the classification criteria of pore structure in the study block were determined,and the evaluation criteria of three types of reservoir fluid properties were established.Based on the characteristics of logging response,the oil and water distribution law of Wulan sag was summarized and the oil test was carried out.The evaluation method of reservoir fluid properties in Wulan sag was carried out to form a complex lithologic fluid property identification method in Wulan exploration area,and an explanatory plate and explanation were established.standardCombined with core nucleus magnetic experiment and core physical property experiment,conventional and imaging evaluation of reservoir characteristics,reservoir interpretation standards and fluid identification methods for andesite and granite were established respectively,and reservoir interpretation plates and corresponding classification criteria were given.The oil content of the reservoir was evaluated by four neutron logging and nuclear magnetic resonance spectroscopy.It was concluded that the nuclear magnetic shift spectrum tailing feature can indicate the oil content of the reservoir.Based on the above analysis,the corresponding reservoir fluid was established.Identify and identify the reservoir reservoir standards,and obtain the corresponding reservoir oil-water interface prediction method.The typical wells of the four blocks in the Wulan Sag of the study block were analyzed for reservoir fluid analysis and reservoir level identification criteria,and the application effect was good.