Geology Reference
In-Depth Information
/
0
-
K
-
h
-
-
h
/
0
x
.
K
x
-
x
-
x
-
x
-
x
!
"
/
0
-
K
-
h
-
-
h
/
0
y
.
K
y
-
y
-
y
- -
y
y
!
"
/
0
-
K
-
h
-
-
h
z
/
0
.
K
z
-
z
-
z
-
z
-
z
!
"
Since
K
x
,
K
y
,
K
z
are very very small, their values can be neglected;
therefore,
2
2
2
-
h
-
h
-
h
-
h
K
K
K
=
Ss
R
x
y
z
2
2
2
-
x
-
y
-
z
-
t
2
2
2
-
h
-
h
-
h
-
h
K
K
K
Ss
R
or
=
(13)
x
y
z
2
2
2
-
x
-
y
-
z
-
t
Equation (13) is the governing equation of the groundwater flow.
Partial Differential Equation of 2nd Order for
Groundwater Flow
-
-
h
-
-
h
-
-
h
h
R s
t
-
Kh
Kh
Kh
G
=
(14)
x
y
z
-
x
-
x
-
y
-
y
-
z
-
z
-
where
s
= storage coefficient;
h
= hydraulic head; and ±
R
= Input/Output.
For Confined Aquifer
The Groundwater flow equation for confined aquifer is
2
2
-
G
h
Rs
t
-
h
-
h
T
T
=
(15)
x
y
2
2
-
-
x
-
y
where,
T
x
and
T
y
is transmissivity in x and y direction and is equal to
T
=
K
*
b
= (m/day)(m) = m
2
/day
where
b
is the saturated thickness of the aquifer.
For Unconfined Aquifer
If the aquifer becomes unconfined,
b
=
h
, so
T
=
K
*
h
and then the above
equation reduces to:
