tivity on the carmel faul

5.2.1 Considerations for comparisons between paleoseismic studies
Although a multi-archival approach is probably the best way to validate the findings
from cave deposits, it is important to consider some additional aspects of the different
research techniques and their results. Speleoseismic research is based on an assumption
that earthquake-related damage can occur to speleothems in a cave that is in the vicinity
of an active fault and not necessarily on it. A damaged speleothem can therefore be an
off-fault type indicator of paleo-earthquakes as well as an on-fault indicator similar to
trenches across a fault trace. Whereas the former records ground accelerations, the latter
records ground rupture.
Paleoseismic trenches are usually dug perpendicular to a known or suspected fault
strand in order to determine the slip vector, and if possible date the slip events. The
accuracy of the findings depends on the type of fault and the types of soil investigated.
The studies cited in this research (Gluck, 2002; Zilberman et al., 2006) detected mainly of
earthquake proxies, such as a shutter ridge or subsiding formations. For the most part the
ages were of general tectonic phenomena such as the beginning or termination of
subsiding through the accumulation of soil in depressions, which are difficult to compare
with the ones yielded from speleo-seismites. It is therefore essential to make the
comparison between the different studies while taking into consideration their inherent
differences.
Lacustrine sediments from fault basins (e.g. Lake Lisan aragonites), which are also
on-fault seismic indicators, could be highly sensitive to any ground acceleration and
could therefore potentially record very small events. By comparison, off-fault caves
would only be damaged by strong events if they are located far from an earthquake
epicenter. If a cave is close to the fault it might record smaller events, which could
damage some of the smaller types of speleothems, but such samples are difficult to date
and are usually highly suspect because of their fragility.
Furthermore, results obtained from dating damaged speleothems indicate time
constraints of a likely event that caused the damage. When such constraints are from both
pre- and post-seismite samples, both yielding similar ages (within the error margin), they
are considered the age of an event. That age, though potentially having an analytical error
of less than 1%, is still not an exact date as would be given by historical, archeological or
even some lacustrine sediment evidence (Migowski et al., 2004). Only by comparing the
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