Mud tracing is utilized in a variety of drilling fluid systems to help define the amount of filtrate invasion throughout coring operations. It is used to achieve more accurate oil and water saturations during the formation evaluation.
D2O is a water-soluble tracer used to treat the water phase of the drilling fluid. As it is non-radioactive and harmless to the environment, it will not hinder disposal or recycling of the drilling fluid. D2O is used to elevate the natural background level of deuterium, which generally ranges from 130 - 150 ppm throughout the world. D2O found in the core during analysis is easily distinguished by its mass from any other water extracted from the sample. The amount introduced to the drilling mud can be manipulated to reflect certain concentrations targeted for the determination of fluid saturations.
Reference:
Weatherford Laboratories, well site services brochure.
