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hydrothermal flows generated in the underlying sedimentary complexes
(Akhundov, Mekhtiyev and Rachinsky, 1976; Rachinsky, 1989). Thus, it
provides the opportunity to evaluate conditions and environment of the
vertical heat-fluid-mass transfer (the effect the extent of freedom of water-
exchange on geothermal regime of a local structure). The correlation in
Figure 7.8 of average geothermal gradients vs. invasion extent of the lower
thermal alkaline water h a shows the inverse relationship in the region. I.e.,
the gradients drastically decrease (formation temperatures vertical distri-
bution levels off) ) with the increased invasion (penetration height) into the
productive sections of lower thermal waters. Figure 7.8 testifies to the same
effect. It establishes the direct correlation of average geothermal gradients
in the reference interval vs. depth to the water type transition zone bound-
ary ( Н tran.zone ). The type of this correlation results in the conclusion that at
the prospects with maximum alkaline water rise (shallowest depth to the
transition zone) the gradients are at minimum. It describes the environ-
ment of leveling formation temperatures up the vertical section.
The veracity of correlations between geothermal parameters, tectonic
attributes of local structures and ground water dynamics (Figure 7.8), as
identified in the South Caspian Depression, is supported by the materials
from other basins. The stated Alpine folded belt regions display qualita-
tively similar type of their definitive geologic factors and mechanisms.
A joint analysis of the stated correlations allows for the following
conclusions:
t Minimum values of geothermal gradient and formation
pressure abnormality coefficients within the framework of a
single correlation on most broken structures with maximum
extent of the injection of their section by thermal fluids
from the underlying sediments show the following: the con-
figuration of temperature field and variation of local highs'
geothermal regime are determined by the water-exchange
parameters in the ambient environment of a large scale
manifestations in Alpine regions of vertical interformational
fluid crossflow.
t The major factor in differentiation of geothermal regimes
on the local structures is the extent of vertical migration; it
is controlled by the throughput capacity of faults, eruption
necks of mud volcanoes, contact zones of diapir formations
with the surrounding rocks, fracturing development areas.
This extent is determined by the degree, to which lower
hydrotherms invade the section;
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