The seismic quest for estimating heavy oil viscosity

Laurence R. Lines, Fereidoon Vasheghani

In heavy oil reservoirs, the enhanced oil recovery (EOR) is largely governed by the mobility of fluids. These EOR methods generally attempt to increase mobility by lowering the fluid viscosity. Hence, it is important to have knowledge of viscosity throughout the reservoir. While viscometers and geochemistry can be used to estimate viscosity from borehole samples, we attempt to estimate viscosity between boreholes. Recent research by Vasheghani and Lines (2009) shows the relationship between heavy oil viscosity and seismic Q. The estimation of Q (inverse attenuation) is attempted using a crossborehole tomography method of Quan and Harris (1997). The combination of Q tomograms and rock physics models is subsequently used to produce estimates of viscosity between boreholes. The details of this research are to be published in the upcoming PhD thesis of Vasheghani (under preparation).