The Effects of Shear Properties of Heavy Oils on Seismic Response

Abstract

Shear properties of heavy oils can influence the seismic response. This is ignored in the elastic modeling approaches. However, heavy oils are considered Viscoelastic materials and the effects of their shear properties on seismic response can be modeled using Viscoelastic approaches. Variations in viscosity will change the attenuation of seismic waves. Biot – squirt flow relations (BISQ) can be used to relate attenuation and viscosity. One order of magnitude change in viscosity is equivalent to one order of magnitude change in quality factor. The importance of using appropriate models for characterizing the heavy oil reservoirs is illustrated by comparing the elastic and Viscoelastic responses to changes only in viscosity. While elastic models are blinds to such changes, viscoelastic models illustrate great sensitivity to changes in fluid viscosity, therefore have the potential for estimating fluid viscosity in the reservoirs.