Geology Reference
In-Depth Information
secondary alkalinity factor locally increases to 10
20%-equiv. (fields/
prospects Hesting - Lower Pannonian, Heizelberg - Lower Pannonian,
Pioneer-Kreizfeld - Middle Pannonian, Sankt-Ulrich-Hauskirchen -
Tortonian, etc.)
A specific feature of ground waters in all water complexes is the presence
beginning at certain depth (about 1,000 m) and increase with physical and
stratigraphic depth in the content of the sulphate-ion from 0.1
−
0.3 in the
upper to 4.0 mg.-equiv. in the lower section's intervals (see Figure 2.22). The
correlation is: SO
2
−
(mg.-equiv.) = 0.16
−
Н
1.949
. The sulphate content in
ground waters is controlled by temperature, which determines the bound-
ary conditions of their preservation against microbial reduction (Kuznetsov,
Ivanov and Lyalikov, 1962; Rachinsky, 1973; Rachinsky and Aliyev, 1973).
This makes the correlation between these two parameters (sulphate con-
tent and temperature) legitimate: SO
2
−
(mg.-equiv.) = 0.75
⋅
10
6
⋅
⋅
10
-6
⋅
t
2.993
(see
Figure 2.23).
Thus, it was established that:
t
Vertical hydrochemical zoning in the region is normal.
Down the section the low-salinity hydrocarbonate-sodium
waters of the upper Neogene water complex are replaced
by the chlorine-calcium brines of the Paleogene-Mesozoic
structure stage;
t
Up the section within the Lower Miocene-Pliocene strati-
graphic interval (Burdigalian-Pannonian Stages) the back-
ground hydrocarbonate-sodium water salinity drastically
declines from 31.9
−
52.6 (9
−
15 g/l) to 10
−
15.5 mg.-equiv.
(3
4.4 g/l). This goes in parallel with an increase in the pri-
mary alkalinity factor values from 6.6
−
9.4 to 70%-equiv.
The Pre-Neogene stage in the nappes' internal zones shows
regional distribution of the chlorine-calcium brines (salinity
455 mg.-equiv. or 130 g/l, secondary salinity factor 22
−
35%-
equiv.) identical in all its intervals. Minimum salinity values
of hard waters go together with the lowermost secondary
salinity factor values (see Figure 2.25);
t
Buried erosion highs of the Paleogene-Mesozoic structure
stage display ubiquitous presence of ground waters with
much lower salinity and hardness compared with waters of
the hydrochemical background typical of the internal parts
of the folded complex nappes.
t
On the Neogene Stage local structures, the hard water
appearance among the alkaline waters is usually localized to
−
