论文信息 - Vp-Vs ratio sensitivity to pressure, fluid, and lithology changes in tight gas sandstones

Vp-Vs ratio sensitivity to pressure, fluid, and lithology changes in tight gas sandstones

Low Vp/Vs anomalies can assist in prospect identification in tight gas sandstone reservoirs, because they are related to good quality rocks (sandstones with low clay content), presence of gas, and overpressure conditions. In such rocks, gas saturation lowers Vp/Vs and the effect is larger if the gas is overpressured. On the other hand, with water saturation, Vp/Vs increases and the effect is enhanced with decreasing differential pressure. Furthermore, tight gas sandstones typically have a Vp/Vs lower than that in shales.

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