SUMMARY Compressional deformation in fluids and rocks is influenced by similar viscoelastic effects, as in shear case. In this paper we introduce the importance of bulk viscosity and modulus in frequency-dependent response of elastic velocities. We conducted experiments to measure bulk modulus and attenuation of two heavy-oil saturated rock samples by confining pressure cycling method under varying oscillation frequencies (within teleseismic frequency band 0.001 - 1 Hz), and compared these measurements to a more conventional axial stress-strain technique. We plan to extend the frequency range of the pressure cycling apparatus as well as to modify the setup in order to measure frequency-dependent bulk viscosities of viscoelastic fluids. INTRODUCTION The bulk modulus of any pore fluid must be used to interpret the seismic response and perform a fluid substitution for Direct Hydrocarbon Indicator analysis.