1) A core is usually 1m or higher and taken during or after drilling, while a plug is a smaller sample cut from the core. 2) Equipment used in the plugging process includes a core plugging machine and Vernier calipers. 3) Properties of rock like porosity, permeability, and saturation can be measured on plug samples in the lab to provide information about the reservoir's properties.

1. Discussion: Jarjis Muhammad
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Q. What is the difference between core and plug?
Ans/ core usually 1m or higher and we do coring job while drilling or after drilling in the wellbore. But plug is
smaller than core, or we can say plug is a part of the core.
Q. What are equipments we used in plugging process?
Ans/
Core plugging machine Core plugging machine Vernier
Q. What are the properties of rock that we get from plug?
Ans/ plug samples provide a lot of data about the reservoir rock properties. With some tests like porosity
measurement, permeability, saturation and other tests that we can do in the lab we get a lot of information about the
reservoir of the field.
Q. Why we use water during core plugging?
Ans/ We use water as a function of mud during drilling operation. To lubricating the bit and clean the cuttings.
Q. Why there are errors in this process.
Ans/ 1- Human errors.
2- If the sample is not completely cylinder. Then we may face errors while measuring the diameter.
3- If there are impurities in the lab equipments.

2. References Jarjis Muhammad
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1- Haliburton. 2007. Core plugging. [ONLINE] Available at: http://www.halliburton.com/en-US/ps/drill-
bits/coring/surface-processing-and-handling/core-plugging.page. [Accessed6 September 2017].
2- Geogas. 2009. Core plugging. [ONLINE] Available at: http://www.geogas.com.au/laboratory/sample-
treatment. [Accessed5 June 2015].