Event 2
In the Nacar Trench, excavated across the
East Anatolian Fault Zone,
Karabacak et al. (2012:310–315) identified a
sequence of surface-rupturing earthquakes recorded
within a narrow (~8–10 m) fault zone cutting both
ophiolitic basement and overlying sedimentary units.
Event 2, which struck between Events 1 and 3, is
defined by fractures observed between the 7th and
8th meters of the trench. These fractures cut units
e and f from below and terminate within unit g,
indicating that rupture propagation did not extend
into higher stratigraphic levels. The upward
termination of deformation within unit g marks a
clear event horizon, demonstrating that younger
deposits were not affected by this rupture.
Unlike Event 1, Event 2 does not produce measurable
vertical displacement or deformation within the
gravel horizons of unit g. This suggests that slip
during this event was either limited in magnitude
or primarily accommodated along existing planes
without generating significant new offset in the
upper units. The absence of displacement in the
overlying gravel layer constrains the rupture to
lower stratigraphic levels.
Karabacak et al. (2012) did not supply a date range for Event 2.
