
Why does volcanism related to the Dead Sea fault occur only where it intersects with the Irbid rift and Harrat Ash-Shaam volcanic field?
Schattner U.(1), Segev A.(2)
(1) School of Environmental Sciences, University of Haifa, Israel
(2) Geological Survey of Israel, 32 Yesha'ayahu Leibowitz, Jerusalem 9692100, Israel
The N-trending Dead Sea Fault (DSF) plate boundary has been developing since the Early Miocene (~20 Ma), gradually separating Sinai from the Arabian plate. Volcanic activity related to DSF displacement mainly occurred along its intersection with the older NW-trending Irbid rift and Harrat-Ash-Shaam (HAS) volcanic field. The question is – why? We re-examine the DSF's structural architecture, the location of eruptive centers, paleo-topographic gradients, and the distribution of volcanic rock accumulation through integrating stratigraphic, geophysical, and tectonic evidence. Our findings show a significant increase in trans-pressure across the DSF of northern Israel at ~5 Ma, preventing magma from ascending along the fault axis. This major shift altered the structural architecture by forming a pair of bends: the Korazim block remained elevated as a restraining bend, while the Kinneret and Hula basins subsided as releasing bends despite compressional stresses. Meanwhile, ongoing HAS rooting and Irbid rifting supported off-DSF volcanism. Their products descended hundreds of meters down steep slopes into the topographic lows along the DSF axis, adding overburden that increased subsidence (e.g., Kinneret, Hula, Yehudiya graben). This dynamic indicates that the DSF and Irbid rifting had opposing effects on melt ascent. This presentation provides the conceptual basis for a field trip to key locations during this meeting.



