Geoscience Reference
In-Depth Information
Fig. 3.23
Dislocated
passage on the ceiling. The
amplitude of the displacement
is 30 cm
Cave. The diameter of the stalagmites ranges between
5.1 and 13.1 cm. The height (H) versus diameter (D)
ratios are 28 B H/D B 36 for the tall stalagmite and
23 B H/D B 28 for the small stalagmite. The results of
the dimension measurements can be seen in Table
3.2
.
The results show that the value of the horizontal
acceleration needed to break the stalagmites is
between 0.143 and 0.438 g. These values are equal to
about VIII-X degrees of the MSK-64 intensity scale.
Samples for U-series dating were taken from the
top and the bottom of the 365 cm stalagmite
(Fig.
3.26
). The dating performed by Dr. Surányi in
Budapest shows that the speleothem is rather young
and its deposition is accomplished in the last
16,000 years. The age of the sample from the base of
the tall stalagmite is 16,200 BP. The sample taken
from the top is aged 1,100.
The results from the study can be interpreted as
evidence of the absence of catastrophic seismic events
during the Subatlantic phase of the Holocene in this
part of Vratsa Mountain.
Fig. 3.24
Rose-diagram of the directions of 16 fallen stalag-
mites in Razhishka Cave
10 m, rich in different speleothems. The high and thin
poplar-like stalagmites are typical rare formations for
Varteshkata Cave.
Two thin stalagmites were studied by Hungarian and
Bulgarian scientists in the Big Chamber of the cave
(Paskaleva et al.
2006
,
2008
; Szeidovitz et al.
2008
).
The tallest is 365 cm high and the other is 140 cm. The
used methodology is the same as that applied in Elata
3.3.1.4 Labirinta Cave
The Stara Planina Iskar Gorge is situated in the
Western Stara Planina Mountains (Western Balkan)
and is one of the remarkable geomorphological phe-
nomena in Bulgaria. The total length of the gorge is
67 km. Labirinta Cave is located in the eastern mar-
ginal part of the gorge, near Cherepish railway station
