Page 242 - Well Logging and Formation Evaluation

232 Well Logging and Formation Evaluation

Exercise 5.3: Thin Beds

The Thomas-Steiber f d/f n plot is as follows:

0.4
0.35
Quartz completely
0.3 replaced by shale

0.25
Clean sand
0.2
Dispersed
0.15
PHId 0.1 Laminated
Structural
100% shale Logs
0.05
0
0 0.1 0.2 0.3 0.4 0.5
–0.05
Sand with 100% shale porefill
–0.1
–0.15
PHIn

The plot shows that the shale is primarily dispersed, rather than struc-
tural or laminated. Hence we can have confidence that our final evalua-
tion is largely correct.
The Thomas-Steiber f d/V p plot and f n/V p plot are as follows:

0.4

0.3
0.2
PORd 0.1

0
–0.1

–0.2
4000 4200 4400 4600 4800 5000 5200 5400
Vp (m/s)