GATE Petroleum Engineering Practice Quiz

Question 1

A dry core plug has a bulk volume of 30 cm^3 and a grain volume of 18 cm^3 measured by helium expansion. What is the porosity of the core plug?

Accepted Answer

40%

Question 2

Two core plugs have identical porosity, mineralogy, and fluid saturation. Plug A has larger, better-connected pore throats than Plug B. Which statement is correct?

Accepted Answer

Plug A is likely to have higher permeability

Question 3

Why is a Klinkenberg correction applied to gas permeability measurements on core samples?

Accepted Answer

To correct for gas slippage at low mean pressures and estimate liquid-equivalent permeability

Question 4

A core sample has total porosity of 24%, but 6 percentage points correspond to isolated pores that do not contribute to flow. What is the effective porosity?

Accepted Answer

18%