Page 217 - Petrophysics 2E

190 PETROPHYSICS: RESERVOIR ROCK PROPERTIES

TABLE 3.16
DIVISION OF DATA OF WELL NO. 1 1 INTO TWO ZONES [55]

Sample Grand Sum
No. per Permeability Cum. Sum of Minus Cum. B W
Group (mD) Permeability Sum (mD2) (mD2) R

1 0.0 10 1,192 13,493 13,600 0.0
2 52 63 1,140 19,892 12,800 0.35
3 276 338 864 243 15,256 0.0
4 140 478 724 3 15,286 0.0
5 139 617 585 102 15,273 0.0
6 156 773 429 1,118 15,146 0.0
7 342 1,115 87 35,646 10,830 0.69
8 87 1,202 0.0 36,120 10,771 0.70
9 0.0 1,202 0.0 16,053 13,280 0.17
10 0.0 1,202 0.0 - - -
SUm 1,202

+ (52)2 + (276)2 + (140)2 + (139)2 + (342)2 +

(87)2 + (0)2 + - -
sz = - - (1, 19a2
1 9
= 13,600

13,600
Iz=l--- - 0.00s
13,493

Because Iz < 0, it is replaced by zero. The other lines are similarly
calculated. Zone II, where k = 0 in samples No. 9 and No. 10, is easy to
identify without any calculations.

Table 3.17 illustrates the next step in zonation of well No. 11, Le.,
division of permeability data into three zones. Zone I1 of the two-zone
division is now divided into two zones. Testeman attempted to divide
the permeability into four zones [55]. He found, however, that the
largest four-zone index (0.79) is smaller than the three-zone index of 0.81,
and concluded that well No. 11 is best described as three permeability
zones.
The permeability data of wells 8, 18, and 37 were divided into zones
using the same approach as for well No. 11. Table 3.18 indicates that
each well is best described by three zones.