tivity on the carmel faul

ages obtained through speleo-seismites to known earthquakes can a specific event be
determined as the cause for damage in karstic caves.
5.1.2 Suggestions for further research
Although mechanisms of structural damage to speleothem formations and cave
environments are not fully understood, it is still reasonable to assume that damage
depends to a great deal on the location of a cave and its distance from an earthquake
epicenter. Denya Cave is located on a spur sloping down to the west of Mt. Carmel, and
as noted above, this area is quite close to the CF system and has many seismic features
(ch. 1.4.2). It seems likely, therefore, that those features are connected to the fault system
and are activated by it, especially since there are no tectonic features on the west side of
the mountain chain. An in depth investigation of the structural features of the northwestern
Carmel might shed some light on the tectonic mechanisms in that area and
perhaps also on likely mechanisms that created the kind of structural features observed in
Denya Cave.
Another consideration that could indicate the source of seismic events recorded in
Denya Cave is in models for seismic loading, as conducted by Marco et al. (in prep.).
Those scholars assessed potential sources for earthquakes that might have caused damage
to the archeological site of Megiddo (Fig. 1). In their model they adopted a slip rate of
0.5mm/y along the CF and then considered three alternatives for estimating the
distribution of that slip along the CF. One of those alternatives suggests that a strong
earthquake (magnitude of 7.2) which ruptured the entire fault (~90km) is consistent with
observed offsets of stream channels reported by Achmon (1986). These scholars’ analyses
showed that that kind of earthquake could be characteristic of the CF if it had a recurrence
interval of several millennia. That seems to be consistent with the findings from Denya
Cave (see ch. 4.3- Seismic events in Denya Cave).
Marco et al. (in prep.) also compared spectral accelerations expected from ruptures
along the two fault systems at Megiddo, given a certain magnitude of earthquake and its
appropriate recurrence. The comparison led them to suggest that the dominant hazard at
the site comes from the CF. However, that conclusion was based on an assumption that
the slip was accounted for largely by moderate earthquakes (examined for a maximum
magnitude M5.5 using the Gutenberg-Richter frequency-magnitude distribution). They
also noted that if that were the case it would be hard to reconcile it with evidence for
surface rupture (Achmon, 1986). On the one hand that observation establishes a
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