Water Permeability in Heavy Oil Reservoirs Near and Below An Initial Water Saturation

Yue Chan
Supervisor: Prof. Zhangxing (John) Chen


Interstitial water in bitumen reservoirs wets on porous media construct a continuous water network, which allows water to flow throughout a reservoir. Being different from conventional oil reservoirs, bitumen reservoirs have high water-to-oil relative mobility ratio, generating considerable effects from initial water movement. Traditional reservoir simulation methods, which are unable to simulate such effects, produced simulation results which can deviate from actual reservoirs. The goal of this study is to investigate the initial continuous water network and its impact on simulations. Differences between the initial water saturation and the irreducible water saturation, which indicates no water movement in simulations, are discussed in terms of their definitions, measurements and effects on simulations.

The implementation of initial water movement into simulations requires a new experimental method to measure the flow capacity of the continuous network. The study combines novel discussions on the continuous network into the development of experimental procedures. A membrane is selected to create the stationary oil phase condition for experimental measurements on the continuous water network and experiments show that the water phase can flow of the order of 0.03-18 milli-darcy at the initial water saturation in measurements. A SAGD case study on initial water movement in a no water flow boundary case is compared with that in a water flow boundary case. Results show that pressure and temperature profiles are altered under tiny amounts of initial water movement outside a thermal zone and the magnitude of error can vary under different simulation inputs.