Geology Reference
In-Depth Information
a)
b)
80
80
70
70
60
60
50
50
40
40
30
30
20
20
Lms
Anhydrite
Dolomite
Chalk
10
10
0
0
0
0.1
0.2
0.3
0
0.1
0.2
0.3
Porosity
Porosity
c)
0.5
0.4
0.3
0.2
0.1
0
0
0.1
0.2
0.3
Porosity
Figure 8.30
Dry rock parameters for selected carbonates (data from Rafavich
et al
.
1984
) and Chalk data from the North Sea; (a) porosity
vs dry bulk modulus, (b) porosity vs shear modulus, (c) porosity vs dry rock Poisson
'
s ratio.
Figure 8.31
A model of dry rock
Poisson's ratio as a function of volume of
shale (modified after Hilterman,
1990
).
DRP ratio varies for
shales depending on
compaction history
Shale
0.35
DRP ratio generally
between 0.1 and
0.25 for sandstones
Sand
0.1
0
100
Clean
sand
Dirty
sand
Clay rich
172
V
cl
