Abstract
In a high-resolution small scale seismic experiment we investigated
the shallow structure of the Wadi Araba Fault (WAF), the principal
fault strand of the Dead Sea Transform System between the Gulf of
Aqaba/Eilat and the Dead Sea. The experiment consisted of 8 sub-parallel
1 km long seismic lines crossing the WAF. The recording station spacing
was 5 meters and the source point distance was 20 m. The first break
tomography yields insight into the fault structure down to a depth
of about 200 m. The velocity structure varies from one section to
the other which were 1 to 2 km apart, but distinct velocity variations
along the fault are visible between several profiles. The reflection
seismic images show positive flower structures and indications for
different sedimentary layers at the two sides of the main fault.
Often the superficial sedimentary layers are bent upward close to
the WAF. Our results indicate that this section of the fault (at
shallow depths) is characterized by a transpressional regime. We
detected a 100 to 300 m wide heterogeneous zone of deformed and displaced
material which, however, is not characterized by low seismic velocities
at a larger scale. At greater depth the geophysical images indicate
a blocked cross-fault structure. The structure revealed, fault cores
not wider than 10 m, are consistent with scaling from wear mechanics
and with the low loading to healing ratio anticipated for the fault.
Users
Please
log in to take part in the discussion (add own reviews or comments).