Cement Evaluation In Oil And Gas
The cement evaluation is necessary for determining the zonal isolation and the top of cement. The position of the top of cement can be established in three ways:

- By the pressure differential method.
- By temperature survey.
- By Electronic logging (USIT/CBT logging runs)

Comparison of the actual TOC with the intended TOC may give an indication that losses (Check also Mud Losses) (unexpectedly low TOC) or channeling (unexpectedly high TOC) have occurred.
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