Interwell Porosity Distribution &

Difference Image

(from Shear & Compressional Interwell Velocities)

Replacement of Pore Fluid by CO2 in this Reservoir Induces a Change in

Apparent Porosity on the Order of Two to Six Percent. 

This Change is Not Readily Interpreted from

the Post-Injection Porosity Image alone (Figure 1 Below),

but is Easily Detected when the Difference in Apparent Porosity

between Post-Injection and Pre-Injection Surveys is

Computed (Figure 2 Below).

4844porcopyrt.gif (16946 bytes)

4844difcopyrt.gif (9322 bytes)