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become open. Under favorable conditions, the ground water even reaches
the surface. This happened in the city of Dolina in the earthquakes of 1975-
1976. At that time highly metamorphic chlorine-calcium brines typical of
deep horizons erupted onto the surface (Kolody, 1983).
In summary, the following may be stated regarding AHFP occurrence:
t Most common occurrence of abnormal pressures in reser-
voirs of the trough's internal zone.
t Occurrence of the maximum abnormality factor values in
reservoirs over crestal zones in the subthrust portions of
local structures and areas of the “skib” (tectonic scale) and
nappe tectonics. These reservoirs are overlain by thick seals
isolated from the discharge foci.
t Decrease in the formation pressure abnormality from the
structural crests to the flanks and plunges.
t Occurrence of minimum abnormality factor values in the
structures of the upper tectonic stage. A typical feature of
this stage is drastically lower regional hydraulic barrier's
thickness and relative closeness of the water reservoirs to the
surface (drainage zone).
t Mosaic distribution of normalized pressure in different
fault-blocks of individual anticlines, their excess over the
hydrostatic and the formation of their gradients and of the
pressure abnormality factor.
Regional AHFP distribution in the vertical section (see Table 3.4) shows
the continuous, beginning in Oligocene, increase in the abnormality fac-
tor with stratigraphic depth. In combination with other direct attributes,
it is an indication of the inter-formational vertical fluid mass-transfer in
the region from the lower to the upper (pre-Miocene) sedimentary sec-
tion interval. These attributes include geotemperature, geo-hydrochemical,
palynologycal, isotopic and other anomalies (Babinets and Malskaya, 1975;
Dolenko, 1962; Zinenko, 1975; Kolody, 1983; Lozinsky and Bankovsky,
1972; Novosiletsky, 1975).
We interpret a drastic (up to 1.63) increase in average abnormality fac-
tor value within thin lens-shaped reservoirs of the Lower Miocene molas-
ses complex (which is a regional seal) as a result of the integral effect of
several factors. They include:
t Invasion from below of high-pressure agents.
t “Injection” of epigenetic AHFP under the hydrodynamic
barrier.
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