Sensitivity Analysis of Effective Fluid and Rock Bulk Moduli Due to Change in Pore-pressure, Temperature and Saturation

In this study, we analyze the sensitivities in effective fluid bulk modulus due to same amount of change in three different input parameters (i.e. saturation, pore-pressure, temperature). We analyze the effects on both the extreme bounds (Voigt bound and Reuss bound) for different fluid combinations (oil-water, gas-water and gas-oil). We find that the change is highest for the gas-water combination and lowest for the water-oil combination irrespective of changes in any parameter. Our results indicate that the sensitivities differ for both the bounds, even for same amount of changes in any input parameters. Our analysis demonstrates that pore-pressure and temperature changes can be vital and sometimes higher than the effect of saturation change. We, also, investigate these effects on porous rock bulk modulus and find that the effect of any input parameter is higher for the softer rocks.