Page 579 - Petrophysics

546 PETROPHYSICS: RESERVOIR ROCK PROPERTIES

3. The inter-porosity fluid transfer coefficient is given by Equation 8.85:

3792 (1.4 x (0.47)(0.2922)
h=
(78.6) (0.22)

= 4.27 x

The high value of fluid transfer coefficient indicates that the fluid
transfer from matrix to fractures is very efficient.

l(b) TDS technique
From Figure 8.32, the following characteristic points are read:

Atmin = 0.22 hrs (t*AP’)R = 10.9 psia (t*AP’)- = 4.76 psia

1. Using the TDS technique, the value of k is obtained from Equation 8.87:

-
k= 70.6qpB0 - 70.6 (17000) (0.47) (1.74) = 78.3 mD
h(t*Ap’)R (1150) (10.9)
2. The inter-porosity fluid transfer coefficient is given by Equation 8.88:

42.5(1150) (1.4 X (0.292)’
- 4.267 x
(17000) (1.74)

3. The storage coefficient o is calculated from Equations 8.91:

0.0002673 x 78.3
= x 0.22 = 80,968.8
(0.47 x 0.2922 x 0.0000014

1
o= = 0.25
2.9114 - 3.5668/ ln(0.70783) - 6.5452/0.70783

The conventional semilog analysis yields the same values of k, o and
h as the TDS technique. The main reason for this match is that both
parallel straight lines are well defined.