Geology Reference
In-Depth Information
2. The Dolinsk type. It formed from mixing of the waters out of
the deeper intervals with paleo-infiltration alkaline waters.
The formation waters are diverse in their chemical compo-
sition and salinity. As the salinity increases, the hydrocar-
bonate-sodium waters turn into the chlorine-calcium waters
through the intermediate chlorine-magnesium waters;
3. The Obolon type. It is typical of the structures where the
discharge of depth-originated chlorine-calcium brines and
their accompanying hydrocarbon was absent and the section
almost completely preserved the alkaline paleo-infiltration
waters.
The following conclusions have been made regarding the hydrochemi-
cal description of ground waters in the Internal zone of the Carpathian
Foredeep and patterns of their spatial distribution:
t
The vertical hydrochemical zoning in the region is in general
normal;
t
The ground water distribution over the area of local struc-
tures and regionally is highly mosaic and indicates its clear
association with the fault tectonics: the most faulted areas
and fault-blocks of local highs and larger geostructures are
saturated with maximum salinity chlorine-calcium brines;
t
Vertical ground water distribution is appropriate for large
interformational ground water crossflows from the lower
into the upper hydrogeological stage with substantially
restricted lateral water-exchange;
t
Local positive anomalies in hydrochemical concentration are
spatially conjugated with conductive fault zones and asso-
ciated structures of rich oil and gas occurrences (Borislav,
Bitkov, Dolina, North Dolina, Tanyava, etc.);
t
The hydrocarbonate-sodium-type ground waters in their
origins are mostly a product of the fresh meteoric water's
ancient infiltration into Oligocene reservoirs. The metamor-
phosed chlorine-calcium brines of the Lower Miocene are a
result of the dissolution and leaching of its evaporites. The
chlorine-calcium brines in the Upper Cretaceous - Middle
Oligocene stratigraphic volume and possibly in the Paleozoic -
Middle Jurassic complex are the derivatives of the normal
metamorphism of depositional waters in the clastic water
reservoirs.
