Detection of top of cement within an annular environment

Abstract

A method for detecting a top of cement (TOC) within an annulus of a subterranean wellbore includes providing a frangible compartment in a wiper plug, frangible compartment containing a detectable material, launching the wiper plug into the wellbore ahead of a cement slurry, causing the wiper plug to strike or land on a casing shoe withing a casing thereby creating an impact that causes the frangible compartment within the wiper plug to be ruptured to release the detectable material into the casing, pumping the cement slurry to pass through the wiper plug such that the released detectable material forms a leading portion of the cement slurry and rises up in an annulus of the wellbore, and detecting the detectable material at a top of cement (TOC) when the detectable material in the annulus passes by a plurality of sensors.

Dependencies are inferred from the claim text.