Other Assessment Methods—An Overview
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bed. Degree of maturation can be delineated by geochemical data such
as vitrinite refl ectance, thermal alteration index, biomarkers, or burial
history. The quantity of oil that can migrate from each source rock bed
may be inferred from these studies by the following equation:
oil generated = Bulk rock volume of source rock
× Organic matter content by volume
× Genetic potential
× Fraction of oil in hydrocarbon yield
(7.1)
× Transformation ratio
× Volume increase on oil generation
The advantages of this equation are the following:
It is deterministic.
1.
It provides a way of calculating an upper limit for the
2.
resources.
It is suitable for plays or basins.
3.
It can be partially validated.
4.
Basin type
I Craton Interior Basins
II Continental Multicycle Basins
A. Craton margin
B. Craton-accreted margin
C. Crustal collision zone
Convergent plate margin
(closed)
(open)
III Continental Rifted Basins
A. Craton and accreted zone rift
B. Rifted convergent margin
C. Rifted passive margin
IV Delta Basins
10
30
50
70
90
Range in percent
Figure 7.1. Basins with various tectonic histories containing different petroleum
resources.