Publications

Seismic attenuation is one of geophysical parameters that is often neglected or even excluded from routine evaluation of vertical seismic profiling (VSP) data related to subsurface work. Q-factors are the terms used in seismic attenuation analysis derived from available seismic datasets and they are utilized to create attenuation model of the earth. The model is potentially an important insight of lithology and petrophysics properties in reservoir characterization. The nature of one-way travel path of propagating seismic waves into the earth media enables VSP to produce direct measurement of seismic signal. Compressional waves in VSP data are attenuated less than those in surface (reflection) seismic data, hence better signal-to-noise ratio (SNR) at high frequencies can be achieved. In this study, spectral ratio method is performed on downgoing P-wave data from zero-offset VSP to estimate Q-factor on various depths. The result shows that attenuation model represented by Q factor plots provides valuable quantity for integrated reservoir characterization in addition to well-to-seismic calibration as the products of VSP.