NMR logging porosity activation and data processing method
核磁共振测井孔隙度观测模式与处理方法研究

Nuclear Magnetic Resonance(NMR) Logging has been widely used in determining porosity of formation.However,it is found that porosity difference between NMR and conventional porosity logging is unacceptable in some oilfields in China.In the paper,Magnetic Resonance Imaging Logging(MRIL)porosity acquisition activation and data processing method are studied.The cause for porosity difference between MRIL and conventional porosity logging is analysed.It is found that there are rich smectite,illite and I/S mixed layer clay minerals in terrestrial sand-shale formation.According to NMR transverse relaxation time T-2 of clay minerals and the allocation of partial porosities near the bin of 4 ms,the new porosity activation and data processing method are given.The reliability of new method is proved in laboratory.