Exploration Insights September 2020 | Page 8

8 | Halliburton Landmark
Petroleum System Elements
Petroleum System Processes
Good Reservoir
Poor Trap
0.63
0.38
Good Source
0.67
Good Preservation
0.61
Good Seal
0.63
Poor Migration
0.33
Good Elements
0.64
Fair Process
0.46
Fair Index
0.54
© 2020 Halliburton
Figure 4> Chart revealing the qualities of a late Carboniferous, coal-charged petroleum system in the East Irish Sea Basin. Note the
occurrence of good-quality petroleum system elements, but some poor-quality petroleum system processes.
USES AND IMPACTS OF THE
SCHEMA
The schema defined above is a holistic way of
appreciating the qualities of petroleum systems
and their potential to retain hydrocarbons. Our
approach provides a systematic evaluation of the
factors that lead to the development of more
efficient petroleum systems. As the scoring is not
reliant on an assessment of the volume of proven
hydrocarbons, it provides a method to compare
the qualities of proven and frontier systems.
An understanding of the quality of petroleum
systems can be used to compare different
petroleum systems within and between basins.
Our schema is semi-quantitative and applied
consistently, so the index can also be used to
identify analogue petroleum systems. This can
be achieved either by utilizing the holistic index
score for the basin, or by selecting the qualities
of individual petroleum system elements or
processes. In the following sections, a number
of use cases are discussed with respect to this
schema, that are illustrated with images for
upcoming updates to the PlayFinder dashboard.
Highlighting High-Risk Petroleum
Systems
The schema can reveal quickly why some proven
petroleum systems are less prolific than others.
The Carboniferous petroleum systems of the
East Irish Sea comprise good-quality, organic‐rich
coals that form a proven source rock, which
has the potential to charge good-quality, late
Carboniferous paralic sandstones, or Permian
to Triassic terrestrial successions. All of the
petroleum system elements seem to have the
appropriate qualities for the development of
a good petroleum system; this translates into
a favorable index score in these categories
(Figure 4).
However, the timing of hydrocarbon charge,
relative to the development of traps, as well
as several episodes of uplift, have reduced the
ability of the petroleum system to preserve
hydrocarbons. Therefore, the index scores for
the processes associated with this petroleum
system are less favorable. This in turn affects the
overall score of this petroleum system. In this