Geology Reference
In-Depth Information
functioning mechanisms of subsurface fluidal medium's decrease in
energy resources.
The law of spatial coincidence between oil and gas occurrences and
regional and local piezometric minima is a conceptual and generalized
expression of the essence of the formation of oil and gas accumulation
zones. It is caused by the integral effect of a number of specific deter-
minants, factors and mechanisms controlling and accompanying this
process.
Thus, regional oil and gas accumulation zones and local areas are con-
joined with geo-fluid-dynamic system's discharge areas and points. This
reveals and clarifies a number of significant aspects in the oil and gas for-
mation and occurrence mechanism and opens conceptually new addi-
tional opportunities for its objective recognition and forecast. In particular,
it becomes uniquely certain that the processes of hydrocarbon accumula-
tion in the reservoirs and formation of oil and gas accumulations and fields
cannot be implemented in a passive hydrodynamical medium, which is
the environment, zones and intervals of regional piezometric maxima and
practically no discharge. This assumes as major condition for the concen-
tration of oil and gas into commercial aggregations (with the observance of
all other necessary and sufficient conditions) the existence of active hydro-
dynamical regime. This regime predetermines the possibility of releasing
the pore and fracture space in geologic bodies from the ground water. This,
therefore, creates in them void volumes for saturating by the migration
agents.
In other words, the realization of natural reservoirs' potential capacity
for oil and gas-saturation is overwhelmingly defined by the dynamism of a
geo-fluid-dynamic system, by the possibility and actual relationships of the
syngenetic water phase evacuation volume from the accumulating inter-
vals and by hydrocarbons entering into them from generation zones. In
this connection, it appears necessary to critically reinterpret and update
the existing notion and interpretation of the term “hydrocarbon trap”; it is
fuirther necessary to expand it with the mandatory consideration of pos-
sible outflow from the reservoir of any morphogenetic modification of the
earlier filling ground water.
It is also obvious from the aforementioned that with all other condi-
tions equal the probability for accumulations, fields and oil or gas reserves
amounts to form is in direct correlation with the scale of ground water
emigration from traps. Besides, it progressively increases with the opti-
mization of conditions for the emergence of accumulating pore-fracture
space. This space is controlled by the conductivity of faults, fracturing
