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of 23 cm are identified three generations of broken
thin stalactites as the first (youngest) one meets the
Ligurian earthquake of 1887 (M
s
= 6-6.5) and the
third (oldest) lies on buried calcite crust aged 35,000
BP (Gilli
1998
).
The group of Gilli carried out successful speleopa-
leoseismologic observations in the Asian part of
Turkey. Studies on the Tilkiler Cave near the
Oymapinar Dam (Manavgat, Taurus Mountains,
southern Turkey) found plenty of broken stalactites on
the floor of the cavern. Some of them were driven
vertically into the sandy sediments, and elsewhere
described earlier clusters of broken stalactites, together
with calcite crust. The cave was discovered shortly
before the visit of Gilli, during the digging of a tunnel
and had no natural entrance. The performed radiocar-
bon dating indicates that fractures-aged stalactites in
Tilkiler are of age 5,000-800 BP (Gilli
1995
).
Gilli performed research in karst areas of Costa Rica
and USA as well. Costa Rican territory is characterized
by very high seismicity—since 1940 registered ten
earthquakes with magnitude of more than 7 (Gilli
1995
). Extensive paleoseismologic studies of the caves
were undertaken in 1994 by the team of Gilli. There
have been many different forms of deformation caused
by active faults (Coredores Cave to Peninsula Osa) and
centimetric displacements of the cross section of cave
galleries. Inclined stalagmites are described in the cave
Tersiopelo—probably a result of the earthquake in
1991 (M
s
= 7.1) (Gilli
1995
).
In the United States deformed speleothems are
found in the caves, Sutherland Peak (Southern
Arizona) Endless Cave, Sand Cave, MacKittrick Cave,
Carlsbad Caverns, and Hidden Cave (New Mexico). In
Sutherland Peak is described broken stalactites—
probably resulting from the impact of Sonora earth-
quake (Mexico, May 3, 1887, M = 7.2). Gilli visited
caves in Carlsbad District of New Mexico character-
ized by the presence of broken speleothems and
breakdowns. The research was hampered by strong
anthropogenic interference, dating from the second
half of the nineteenth century in the Carlsbad Caverns
National Park (Gilli and Serface
1999
).
Panno from the Illinois State Geological Survey
and his coauthors published a study on caves located
within 250 km of the New Madrid Seismic Zone
where established stalagmites with deviated axes of
grown and fallen stalagmites recovered with active
new stalagmites. The data from the accomplished
U/Th mass spectrometric dating of three speleothems
show the influence of single seismic event (Panno
et al.
2009
).
Research in the Brujas Cave in the southern Andes,
Argentina was carried by Sancho et al. (
2003
). In
hardly accessible passages are identified clusters of
broken stalactites, which are interpreted as a sign of a
seismic event with Pre-Holocene age. Franko Urbani
reported for rotated rock blocks and fractured spele-
othems as indices for paleoseismicity in Guanasna
Caves near Caracas, Venezuela (Urbani
2002
).
The method of Prof. Paolo Forti from the
University of Bologna, Italy, was founded on the
belief that stalagmites are natural pendulums and
respond to changes in the cave floor. Selected sta-
lagmite samples are cut longitudinally and the vari-
ance of their growth axis is interpreted as evidence of
the impact of earthquakes. The result of the compar-
ison between the time series variations in stalagmite
sections and corresponding catalogs of earthquakes
represents a clear correlation. For example, in sta-
lagmites from the caves Buko dei Buoi and Spinola in
the vicinity of Bologna is established abrupt deviation
from their axes of growth, corresponding to the
earthquake of January 3, 1117—the strongest in
northern Italy. In the studied stalagmites are found
traces of three seismic events earlier than 1117 (Forti
and Postpischl
1984
,
1987
).
Within the last years, tectonic studies in karst in
Slovenia were generally performed by Dr. Stanka
Šebela and her collaborators from the Karst Research
Institute in Postojna. In 2004, four extensometers
were installed in caves and two of them mounted in
Postojna Cave (Gosar et al.
2011
; Šebela
2008
,
2009
,
2010
; Šebela et al.
2005
).
Pérez-López and others (2009) found a coseismic
ceiling block collapse occurred at -156 m in Benis
Cave (-213 m, SE Spain), associated with the Mula
earthquake (1999, M
b
= 4.8, VII MSK). Their anal-
ysis suggests that an active fault segment determined
the morphology of the cave, where strong paleo-
earthquakes (6 B M B7) took place. As a conse-
quence of this intense seismic activity, a cave gallery
collapsed
and
a
new
seismothem
was
recognized
(Pérez-López et al.
2009
).
The intensity of one of the most destructive
earthquakes in Switzerland and Western Europe
(Basel earthquake, October 18, 1356) is measured
between
VIII
and
IX
MSK.
French
and
Swiss
