Seismic low-frequency effects from oil-saturated reservoir zones
Goloshubin, G.M.; Korneev, V.A.; Vingalov, V.M.
SEG Annual Meeting Expanded Technical Program Abstracts with Biographies 72: 1813-1816
We consider the frequency dependence of seismic reflections from a thin (compared to the dominant wavelength), fluid-saturated reservoir for the cases of oil and water saturation. Reflections from a thin, water or oil -saturated layer have increased amplitude and delayed travel time at low frequencies if compared with reflections from a gas-saturated layer. This effect was observed for both ultrasonic lab data and seismic field data. One set of field data revealed high correlation of low frequency processed image for two different production horizons represented by fractured shale and sandstone. Another set was processed for the purpose of contouring of oil/water contact, and reveal very good correlation with available well data. The frequency dependent amplitude and phase reflection properties can be used for detecting and monitoring thin liquid saturated layers.