Morphologic dating of fault scarps and terrace risers in the southern Arava, Israel: comparison to other age-dating techniques and implications for paleoseismicity

Fault scarps and terrace risers in the southern Arava, Israel, were analyzed to determine the applicability of morphologic dating through a diffusion modeling approach a) as an estimator of age and b) as a relative age dating tool. Using diffusion modeling we were able to differentiate between slopes that varied in age, based on soil-geomorphic studies, by only a few thousand of years. The modeling results indicate that the specifically studied fault scarp is between 50 000 and 17 000 years old. The morphologic age determined by the modeling agrees well with the correlative age from earlier soil and geomorphologic studies and with recently acquired optically stimulated luminescence (OSL) dates. Scarp diffusion modeling provides acceptable estimates of ages of faulting events in a region where other age dating methods (numeric or correlative) are non-existent or rare, time-consuming, or very expensive. In addition, the ability of the modeling to distinguish between scarps of different ages provides us with a tool to group the numerous fault scarps in the southern Arava according to their morphologic ages and to help in tectonic analysis of that region. -from Authors