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HYPOGENIC CAVE FEATURES
Eastern Europe
The great artesian basins of the Eastern European
craton provide many excellent examples of hypogene
transverse speleogenesis.
In the Prichernomorsky artesian basin, south Ukraine,
beneath the city of Odessa many small caves were
intersected by extensive mines in a single limestone bed
within the Miocene carbonate sequence, a drained part of
the regionally extensive artesian system. The caves
represent isolated slot-like passages (Figure 31-A) and
crude clusters of intersecting passages (B), the longest
cave being a relatively small maze with 1.4 km of mapped
passages. These caves are simple and unambiguous
examples of transverse speleogenesis; most passages
laterally terminate as narrow, apparently declining fissures.
They were formed by direct flow between the lower and
upper boundaries of a particular limestone bed that
contains a single-story intrastratal set of fractures, which
are poorly connected laterally.
Among the world's foremost examples of hypogene
(confined) transverse speleogenesis are the extensive caves
in the Miocene gypsum in the western Ukraine (Figure 32).
These are 3-D (multiple-story) network mazes confined
within a single 16-20 m thick gypsum bed, sandwiched
between two aquifers. The study of their patterns and
morphology, along with the regional hydrogeologic
analysis, have served as a foundation that firmly
established the artesian transverse origin for the caves and
the conceptual framework presented in this book
(Klimchouk and Rogozhnikov, 1982; Klimchouk and
Andrejchuk, 1988; Klimchouk, 1992, 1994, 1996c, 2000b).
The caves and their regional settings are discussed
elsewhere in this book, and more details can be found in
the cited sources. It is important to mention, however, that
in the confined zone of the same aquifer system, numerous
cavities encountered by exploratory drilling show
morphometric characteristics and distribution (in both plan
view and cross-section) consistent with the patterns of the
explored relict caves (Klimchouk, 1997c).
Figure 32. Patterns of hypogenic maze caves in Miocene gypsum in the western Ukraine. The region contains the five longest gypsum
caves in the world. The longest is Optymistychna, with 214 km of mapped passages (Figure 12). The second and third longest gypsum
caves are Ozerna (117 km) and Zoloushka (90.2 km) shown here. Maps are courtesy of the speleological clubs of Ternopil' (Ozerna,
Kristal'naja, and Mlynki), Chernivtsy (Zoloushka), and Kiev (Slavka).
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