25)What is the correct formula of the average permeability, parallel to the bedding planes.

a) K = ( 〖 K〗_1 Z_1+ K_2 Z_2+⋯+K_n Z_n)/Z x 1/2

b) K = 1/(〖 Z〗_1/〖 K〗_1 + 〖 Z〗_2/〖 K〗_2 +⋯+〖 Z〗_n/〖 K〗_n ) x 1/2

c) K = Z/(〖 Z〗_1/〖 K〗_1 + 〖 Z〗_2/〖 K〗_2 +⋯+〖 Z〗_n/〖 K〗_n ) x 1/3

d) K = ( 〖 K〗_1 Z_1+ K_2 Z_2+⋯+K_n Z_n)/Z

Komal Bhandakkar Answered question January 5, 2021

**Answer: d) K = ( 〖 K〗_1 Z_1+ K_2 Z_2+⋯+K_n Z_n)/Z**

Explanation:

- When the flow is parallel to the bedding plane, then the total discharge is the sum of discharge through the individual layers.
- i.e. q= q_1+ q_2+…+ q_n q= ∑ k_i z_i
- Therefore, the value of the coefficient of permeability which is parallel to the bedding planes is,
- K = ( 〖 K〗_1 Z_1+ K_2 Z_2+⋯+K_n Z_n)/Z

Komal Bhandakkar Edited answer January 5, 2021