Application Research Of Pulsed Neutron Full Spectrum Logging Technology In X Heavy Oil Field

In the middle and late stages of oilfield development,it is more and more difficult to exploit.It is very important to understand the distribution of remaining oil and monitor the dynamic change of remaining oil in reservoir under the condition of flooding during oilfield development,so as to formulate reasonable development measures and improve oil recovery.Therefore,the development of high-level reservoir dynamic monitoring technology is an important link to solve the problem of oilfield development.At present,in the process of oilfield development,the remaining oil saturation monitoring mainly includes pulse neutron logging technology and casing resistivity logging technology,but pulse neutron saturation logging technology is still the most commonly used technology.According to the geological characteristics of heavy oil in X oilfield,the basic theory of related technology is studied,and the applicable conditions and processing and interpretation methods are understood.Finally,a set of data processing and interpretation methods of pulse neutron full spectrum saturation logging is formed,which provides necessary technical means for residual oil dynamic monitoring in X oilfield.Through literature research at home and abroad,we can understand the development status of pulsed neutron logging technology,and have a clear understanding of remaining oil saturation logging technology at home and abroad.At the same time,the existing residual oil saturation instrument monitoring methods are summarized,and their residual oil evaluation capabilities are compared and their limitations are analyzed.Based on C/O logging principle,the principle of pulsed neutron logging method in heavy oil area is deduced,and the response characteristics of different lithology,porosity and shale content to residual oil distribution are simulated and compared.A set of PSSL pulsed logging interpretation method in heavy oil area is obtained.In order to realize the PSSL pulse neutron full spectrum residual oil saturation logging interpretation method,based on the measured data of X oilfield,starting with the full spectrum and naked eye original spectrum data,the smoothing and spectral drift correction of energy spectrum data are completed.The calculated C/O,Si/Ca and Sigma curves are applied to the calculation of oil saturation in formation to improve the coincidence rate of residual oil monitoring.Full spectrum data is used to calculate oil saturation,and volume model is established to determine oil and water line parameters according to actual well data in order to adapt to different logging environments.Full spectrum saturation logging method calculates oil saturation by measuring formation parameters such as C/O ratio and Si/Ca ratio.Finally,PSSL technology is applied to the application and testing of tracing method in actual development wells in X oilfield,and10 measured full spectrum data are processed.According to the follow-up results of perforation and plugging in each well,the interpretation coincidence rate of all wells is over90%.After three months of measures,about 20 t/d of oil was added,which brought about economic and social benefits.