Abstract
High-resolution seismic tomography and magneto-telluric (MT) soundings
of the shallow crust show strong changes in material properties across
the Dead Sea Transform Fault (DST) in the Arava valley in Jordan.
2D inversion results of the MT data indicate that the DST is associated
with a strong lateral conductivity contrast of a highly conductive
layer at a depth of approximately 1.5 km cut-off at a position coinciding
with the surface trace of the DST. At the same location, we observe
a sharp increase of P wave velocities from <4 km/s west of the fault
to >5 km/s to the east. The high velocities in the east probably
reflect Precambrian rocks while the high electrical conductivity
west of the DST is attributed to saline fluids within the sedimentary
filling. In this sense, the DST appears to act as an impermeable
barrier between two different rock formations. Such a localized fluid
barrier is consistent with models of fault zone evolution but has
so far not been imaged by geophysical methods. The situation at the
DST is remarkably different from active segments of the San Andreas
Fault which typically show a conductive fault core acting as a fluid
conduit.
Users
Please
log in to take part in the discussion (add own reviews or comments).