Non‐Triggering and Then Triggering of a Repeating Aftershock Sequence in the Dead Sea by the 2023 Kahramanmaraş Earthquake Pair: Implications for the Physics of Remote Delayed Aftershocks.

Most aftershocks occur in areas experiencing large co‐seismic stress changes, yet some occur long after the mainshock in remote lightly stressed regions. The triggering mechanism of these remote delayed aftershocks is not well understood. Here, we study aftershocks occurring in the Dead Sea (DS) area following the 2023 Mw7.8 and Mw7.6 Kahramanmaraş earthquakes. Most aftershocks cluster along previously quiescent structures off‐ the main DS fault strand. Visual inspection disclosed three aftershocks instantaneously triggered by the Mw7.6 in the northern DS basin, and match‐filtering revealed a delayed aftershock. Waveform similarity and temporal clustering suggest the northern DS aftershocks re‐rupture a stick‐slip patch loaded by surrounding creep. Velocity‐gradient seismograms show the Mw7.6 exerted larger transient stresses than the Mw7.8, which may explain triggering by the Mw7.6, but not by the Mw7.8. This account of instantaneously triggered repeaters underscores the role of interactions between aseismic and seismic slip in remote triggering. Plain Language Summary: Most aftershocks occur in areas experiencing large co‐seismic permanent stress changes, yet some occur long after the mainshock in remote regions experiencing small stress changes. The physics controlling the triggering of remote delayed aftershocks is not well understood. Here, we report on remotely triggered aftershocks in the Palestine Territories and Israel following the 2023 Kahramanmaraş earthquake pair. The main fault within the study area is the Dead Sea (DS) Transform (DST), yet most aftershocks occur on secondary structures located off‐ the main DST fault strand. This indicates off‐fault structures are presently more pre‐stressed than the main DST fault, which has important implications for seismic hazard analysis. We document a sequence of four aftershocks re‐rupturing the same fault patch in the Northern DS basin. Three of these aftershocks were triggered during the Mw7.6 surface‐wave passage, and one aftershock is delayed. We do not observe triggering in the study area due to the larger and closer Mw7.8. The non‐triggering by the Mw7.8 and later triggering by the Mw7.6 is explained in terms of the mainshock source properties. The aftershock decay rates and moments are consistent with a model in which a stick‐slip patch is being loaded by creep in the surrounding area. Key Points: We document a dramatic earthquake rate increase in the Palestine Territories and Israel following the 2023 Kahramanmaraş earthquakesWe provide the first account of instantaneous remotely triggered repeating aftershocks triggered by the Mw7.6 mainshockNon‐triggering by the Mw7.8 and later triggering by the Mw7.6 underscores the role of aseismic and seismic fault slip interactions [ABSTRACT FROM AUTHOR]