Page 26 - Geology and Geochemistry of Oil and Gas

NATURAL SYSTEMS AND THEIR CLASSIFICATION 5
created C must yield a negative result. The writers failed to find any publication that
contained rules (or just recommendations) for the inductive development of C. It
appears that in order to overcome the transition step from analysis to synthesis one
needs to develop corresponding branches in formal logic.
One reason that makes the application of formal logic in geology so difficult is the
nature (properties) of studied objects. Geology studies objectively existing things
(bodies). These bodies are reflected in the subject studied only to some extent of
reliability, which is sometimes quite low. Formal logic, on the other hand, deals with
abstract concepts (products of thought) that are clearly delineated by the corre-
sponding terminology and definitions.
Let us consider a ‘‘set’’, one of the founding concepts in formal logic. Any C
begins with the selection and description of a set. To classify, the set must be selected
and somehow delimited. Within a whole set, mathematical logic considers some
population of objects that have at least one common essential parameter. Nobody
would try to combine into a single set items such as an oil accumulation, a solar
eclipse, a geologic structure, and time. Such a ‘‘set’’ would be incorrect from the
viewpoint of formal logic. At the same time, for some reason, it is believed as quite
feasible to consider the following as a single set: oil (or gas) accumulation, trap, field,
region, prospect, area, basin, province, and tectonic structure (starting with the
region, prefixed with a word ‘‘petroleum’’). Despite a significant mess with defini-
tions in petroleum geology and absence of a clear-cut terminology, it is still possible
to conclude that the above ‘‘set’’ includes:
(a) substance (accumulation), which has quantitative and qualitative parameters;
(b) surface (area, territory, etc.), which can be measured, e.g., in square meters;
(c) geologic structure, i.e., spatial configuration of the Earth’s layers (here, even
volume does not reflect the essence); and
(d) time (for the cases when a basin or a province is considered in the process of
evolution).
It is obvious that a C (especially a hierarchical one) developed for such a ‘‘set’’ is
an absurdity. Nevertheless, the C’s developed for such a ‘‘set’’ or portion thereof is
accepted by petroleum geologists. The very definition of the concept of the ‘‘set’’ in
formal logic is an ‘‘aggregate of objects’’, which implies the discrete nature of the
‘‘set’’. In geology, on the other hand, what is classified is ‘‘continuity’’, a unity of
interconnected processes or their outcomes. They are just conditionally separated for
the purpose of analysis. Also, when one follows the steps of the geologic hierarchy, a
qualitative quantum leap occurs, as new properties appear and old ones disappear.
In the above ‘‘set’’, genetic associations may be established among many of its
constituents. We do mean associations, not transitions (i.e., changes in the properties
of one object depend on the status and properties of some other object). Thus, we
can observe numerous attempts to develop genetic C’s, sometimes natural C’s, at the
time when no methodology exists in the formal logic as to how it should be done.
The concept of a ‘‘set’’, as defined in formal logic, may be used only quite con-
ditionally in geologic sciences. As an example, let us discuss the ‘‘minerals’’ set.
Minerals are an open population, characterized by complex combinations and nu-
merous patterns in their association and neoformations that change with time in the