SP Flashcards
1
Q
What are the three components of SP?
A
- Liquid junction potential
- Membrane potential (Nernst Potential)
- Electro-kinetic potential
2
Q
What mud is required to develop an SP?
A
Conductive mud
3
Q
What is liquid junction potential?
A
Driven by a concentration gradient, the solvated Cl ions diffuse faster than the solvated Na ions, resulting in a charge separation which is by definition a potential.
4
Q
What is membrane potential?
A
The fixed negative charges present on clay minerals block the negative Cl ions from diffusing through. The positive Na ions will diffuse through resulting in a charge separation or potential.
5
Q
What is electro-kinetic potential?
A
Diffusion of ions across a membrane induced by a pressure drop. Effect is very small.
6
Q
What parameters can be derived from SP?
A
Rw and N/G
