Cross-Wavelet Analysis of Well Log Data

In this work cross wavelet analysis is used to perform a series of cross correlation and complexity analysis of raw well log data. Cross wavelet transform (XWT) and wavelet coherency are used to show possible connections between natural gamma ray radioactivity (CGR) of earth and other log data such as Neutron Porosity (NPHI), Sonic Transient Time (DT), Bulk Density (RHOB) and Electrical Resistivity (ILD) of oil and gas reservoirs. The casual relationships CGR log data and porosity logs in the depthfrequency space were also demonstrated. Cross wavelet analysis reveals that the links between CGR and NPHI is stronger than that between CGR and DT or CGR and RHOB. The CGR has a minor effect on the ILD at any scale

Keywords:

Cross wavelet , Sonic Transient Time , CGR log , Electrical Resistivity , natural gamma ray