Multiple lines of evidence indicate that the 2023 Mw 7.8 Kahramanmaraş (Türkiye)
earthquake started on a splay fault, then branched bilaterally onto the nearby East Anatolian
Fault (EAF). This rupture pattern includes one feature previously deemed implausible, called
backward rupture branching: rupture propagating from the splay fault onto the SW EAF
segment through a sharp corner (with an acute angle between the two faults). To understand
this feature, we perform 2.5-D dynamic rupture simulations considering a large set of …

Multiple lines of evidence indicate that the 2023 Mw 7.8 Turkey earthquake started on a
splay fault, then branched bilaterally onto the nearby East Anatolian Fault (EAF). This
rupture pattern includes one feature deemed implausible, called backward rupture
branching: rupture propagating from the splay fault onto the SW EAF segment through a
sharp corner (with an acute angle between the two faults). To understand this feature, we
perform 2.5-D dynamic rupture simulations considering a large set of possible scenarios. We …