Diagram representing the movement of water in the subsurface over time and how it gets trapped in rocks

Measurement of the trapped water can give information past water conditions in the subsurface.

Resistivity from oil-water inclusions (ROI™)

CSIRO's ROI™ technique has many advantages for the petroleum industry.

  • 13 December 2005 | Updated 14 October 2011

Resistivity from oil-water inclusions (ROI™) is a technique used to determine water saturation in oil reservoirs.

Advantages

The advantages of using ROI™ are:

  • it excludes fluid contamination from filtrate
  • it excludes spurious resistivities from groundwater flows
  • water resistivities can be obtained in areas where water samples cannot be taken.

Uses

CSIRO uses ROI™ to observe:

  • water saturations in oil reservoirs
  • resistivity of irreducible water.

Background and technical information

In the ROI™ technique inclusions of oil and water are frozen and the melting temperature of the water part is measured to determine the resistivity of water in the reservoir at the time of accumulation of oil. 

Resistivity from oil-water inclusions is a technique used to determine water saturation in oil reservoirs.

Depending on the age and fill history of hydrocarbons in the reservoir this provides a useful guide to the resistivity of irreducible water, a critical parameter used to determine water saturation in the reservoir.

Learn more about CSIRO's work in Energy from Oil & Gas.

ROI™ is a registered trademark of CSIRO Australia.