Sedimentological Control Parameters and Compaction ...
09~~--------------------------~
09
0.65
0.6
- - Regression
95% confld.
0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95
Predicted porosity
381
Fig.5 Physical-sedimentological porosity model, predicted
versus observed values
One can calculate the influence on porosity of each factor by multiplying the
estimated factors with the range of the different parameters. These values show
that porosity at about equal parts is governed by grain size distribution, content
of organic matter and effective pressure. In other words, sedimentological composition clearly dominates the porosity distribution near the sediment surface,
while effective pressure at a depth of about 2 m and deeper becomes the most
important factor.
Table 2 Coefficients of the physical-sedimentological porosity model
Data
fo
fe
fm
Is
(reference)
Endler
Gustavs
0.868
0.789
1.21 X 10 2
-5.99 X 10 3
4.53 X 10 3
2.46 X 10- 2
-6.27 X 10- 3
4.43 X 10- 3
Table 3 Influence of components on porosity
b
7.2 X 10 5
4.1 X 10- 5
Component
Min ... max, range (Endler data)
Change of (JJ
Min ... max, range (this work)
(parts of 1.0)
C org
0 ... 10(%), 10
0.10
0 ... 8(%), 8
0.20
Mean
10 ... 50(!-Im), 40
0.25
8 ... 68(!-Im), 60
0.35
a
10 ... 30(!-Im), 30
0.10
5 .. .45(!-Im), 40
0.10
Peff
0 ... 2000(Pa), 2000
0.15
0 ... 2000(Pa), 2000
0.10