Oil and Gas Glossary
A B
C D
E F
G H
I J
K L
M N
O P
Q R
S T
U V
W X
Y Z
Z
|
zonal isolation |
Refers to the state or quality with which the
fluids in one permeable zone can be kept separate from those
fluids of another. Zonal isolation is created and maintained
in the well bore by cementing the production string in place
and by appropriate use of casing plugs and packers. Beyond
the well bore radius and inside the formations, zonal isolation
is a function of the existence of permeable barriers such
as impermeable shale members, dense sediments, or cap rock.
The quality of zonal isolation is directly related to the
quality of the cement and bonding which is found between casing,
cement sheath, and formation; and to the degree of or lack
of permeability of the members which can serve as permeability
barriers. |
|
