Velocity is one of the critical parameters in rock characterization. In viscoelastic materials, it may vary with frequency, called as velocity dispersion. Laboratory experiment for measuring velocity in the seismic frequency range in is very important to simulate what is happening in the field. Scaling problem occurs when the small-scale laboratory experiment does not match with large scale in the field. Elastic moduli are acting as an agent of this velocity variation. How rock frame, pore fluid, and stresses play a critical point in this characterization is the key questions to be addressed.

This paper presents a literature study from various data set of a porous media such as limestone, sandstone, shale, and aluminum. The role of pore fluids, stresses, and temperature also incorporated. These data include three velocity measurement techniques: resonance bar, stress-strain dynamic stress, and ultrasonic methods. This paper also presents some experimental data using the sophisticated well-designed instrument and sensor. The result also presents a comprehensive analysis of all gathered data.

To sum up,  the study about frequency dependent of elastic moduli and velocity is very important to understand the characteristics of the rock frame and pore fluid saturation. The ability and reliability of laboratory measurement play a critical role to simulate a real condition in the field. Therefore, we can anticipate and estimate how the reservoir behaves and react during fluid production or injection