Which of the following is necessary for the generation of electrokinetic potential across well-bore and permeable rock formation?
Show Hint
- Salinity gradient
- Pressure gradient
- Shale membrane
- Mud cake
The Correct Option is B
Solution and Explanation
- The driving requirement is a pressure gradient across the permeable medium; without flow, no streaming current forms.
- A salinity gradient produces a diffusion potential (not electrokinetic).
- Shale membranes and mud cake affect SP profiling but are not the necessary driving cause for electrokinetic potential.
Hence, a pressure gradient is necessary.
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