It can be beneficial to be able to determine a presence, displacement, type or other characteristic of fluids or other substances in an annulus in a well. For example, a quality of a cementing operation can be compromised by incomplete displacement of fluid from an annulus by cement, or by mixing of the fluid with the cement. For this reason and others, it will be appreciated that advancements in the art of monitoring substances in a well annulus are continually needed.
USPTO Backgrounds
USPTO Backgrounds