Tracers are used in the

oil industry The petroleum industry, also known as the oil industry or the oil patch, includes the global processes of exploration, extraction, refining, transportation (often by oil tankers and pipelines), and marketing of petroleum products. The larges ...

in order to qualitatively or quantitatively gauge how fluid flows through the reservoir, as well as being a useful tool for estimating residual oil saturation. Tracers can be used in either interwell tests or single well tests. In interwell tests, the tracer is injected at one

well A well is an excavation or structure created in the ground by digging, driving, or drilling to access liquid resources, usually water. The oldest and most common kind of well is a water well, to access groundwater in underground aquifers. The ...

along with the carrier fluid (water in a waterflood or gas in a gasflood) and detected at a producing well after some period of time, which can be anything from days to years. In single well tests, the tracer is injected into the formation from a well and then produced out the same well. The delay between a tracer that does not react with the formation (a conservative tracer) and one that does (a partitioning tracer) will give an indication of residual oil saturation, a piece of information that is difficult to acquire by other means. Tracers can be radioactive or chemical, gas or liquid and have been used extensively in the oil industry and hydrology for decades."Using Tracer Technology In Unconventional Wells"
''Hart Energy''. Retrieved 2023-06-20.

References

Petroleum engineering {{Petroleum-stub