tivity on the carmel faul

pre samples, DN-7 post samples and DN-9 pre samples- photographic view in Appendix
I-II). Those samples yielded 230 Th/ 232 Th calculated values between ~200 and ~2 (Table
3a). The correction factors established from these samples varied between ~0.08 and
~0.19 for five different calculations, yielding an average value of ~0.7 (Table 3b). These
values are similar to the values obtained from detritus-rich speleothem isochron samples.
These three attempts of creating isochron plots in order to obtain correction values
clearly show the complex nature of detrital matter within them. The most likely cause of
scatter in isochrons is not the sampling methodology used in this study, but a combination
of more than one source of initial Th; (1) detrital Th, (2) hydrogenous Th adsorbed to
detritus and oxides (3) hydrogenous Th directly incorporated by carbonates (Richards and
Dorale, 2003 and references therein). Different sources of initial Th may explain the
scattered isochrons demonstrated in Tables 1b, 2b and 3b.
There are several processes which may explain various Th sources in speleothems.
During a depositional hiatus the outer lamina of a speleothem is exposed to the cave
environment for an extended amount of time, allowing detrital matter to settle on it.
Consequently, that lamina may contain a large amount of detrital Th. These hiatuses
could potentially be the result of a change in hydrological settings in a karstic cave due to
seismic events. Such changes in hydrological settings might also allow for an
incorporation of hydrogenous Th into the cave system. Furthermore, when a cave
undergoes an earthquake event, detrital material might rise up from the cave's walls and
floor due to collapses, or it might enter more readily from the surface due to openings of
cracks and ground shaking. This material may embed itself within the outer or broken
laminae of speleothems. It is therefore not surprising that some seismite samples appear
to have a higher detrital content than the underlying laminae of the same speleothems.
This however, is not the case with all seismite samples from Denya Cave, which do not
all contain a noticeable amount of detrital matter (Table 4). It is therefore likely that the
amount and composition of detrital material in seismite samples varies quite significantly
and that no single correction value can be found for these samples.
The above mentioned correction values were deemed unusable for Denya Cave
speleo-seismite age corrections, since the variations in factors are too great in such low
values as to enable the use of an average factor. When applied, they make an extremely
significant difference to most of the calculated ages obtained in Denya Cave, making it
crucial to be more accurate. Moreover, accurate calculations of the slopes and y-intersects
of the isochrons, using the errors of the isotopic ratios (with Isoplot3.7), yielded
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