We have measured the orienta-

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The Dead Sea transform (DST) is the suture between the African and the Arabian plates, both of which subduct northward under the Eurasian plate. The collision of these plates with Eurasia and their relative motion are the source for their internal deformation, especially in the vicinity of the Dead Sea transform. Geological observations indicate that two distinct paleostrain regimes operated adjacent to the Dead Sea rift and in the Sinai‐Israel subplate: (1) WNW shortening (less than 10%) and NNE extension, beginning in the Turonian, is associated with the development of the Syrian Arc fold belt and attributed to the Syrian Arc stress field (SAS); and (2) middle Miocene to Recent NNW shortening and ENE extension, associated with the 105‐km sinistral displacement along the Dead Sea transform and the opening of the Red Sea, is attributed to the Dead Sea stress field (DSS). It was originally suggested that the SAS terminated during the middle Miocene with initiation of the DSS. However, trend and age analysis of many structures shows that formation of SAS‐compatible structures continued after the middle Miocene up to the Recent. In some middle Miocene and younger rocks structures, such as faults, dikes, volcanic lineaments, and tectonic stylolites compatible with both stress fields were reported. In a few locations, structures compatible with both stress fields crosscut each other. It is suggested that the movements which resulted in the development of the Syrian Arc and other SAS‐compatible structures are continuing to the Recent and that DSS movements are superimposed upon them. The overlapping of SAS and DSS structures adjacent to the DST results from spatial and temporal fluctuations in the overall stress state. We propose that such variations could be caused by the superposition of large earthquake stress drops, associated with movements along the DST, on a steady background, plate scale, stress regime associated with the SAS. Thus DSS‐compatible structures should form in preseismic activity periods, when DST‐related elastic strain is high. On the other hand, the SAS‐compatible structures should form during interseismic activity times, subsequent to large local stress release along the DST.

The Holocene sequence of the fan-delta of Nahal Darga, in Israel, records deformation associated with earthquakes related to the Dead Sea Transform in general and to the Jericho Fault in particular. The fan-delta sequence is well exposed, and 20 radiocarbon ages help to date the earthquakes that are inferred from (a) displacement along faults, (b) liquefaction features associated with 11 separate sandy and silty layers, and (c) slumped allocthonous bodies of sediments located directly above one of the main splays of the Jericho Fault. On average, an earthquake larger than M 5.5 has occurred approximately every 600 years. This estimate is based on the earthquake record of the complete stratigraphic sequence, with erosional hiatuses omitted from the calculations. The most recently deformed layer is related to the 1927 Jericho (ML 6.2) earthquake. This layer provides a modern analog for the style of soft-sediment deformation associated with earthquakes in the late Pleistocene and Holocene silty sand beds of the fan-delta complexes of the Dead Sea and its predecessor, Lake Lisan.