Surface rupture history and 18 kyr long slip rate along the Pazarc?k segment of the East Anatolian Fault

We investigate the palaeo earthquakes and slip rate on the Pazarc & imath;k segment of the East Anatolian Fault, which was involved in the surface rupture of the 6 February 2023 Pazarc & imath;k-Kahramanmara & scedil; earthquake (M-w 7.7) and provided insights into the long-term behaviour of this major continental fault. Palaeoseismological data from two trench sites reveal evidence for at least five surface ruptures in the Holocene Period. The historical earthquake of AD 1114 is verified at both trench sites but the following event of AD 1513 is identified at only one site. In addition, the age difference of the older events shows that historical activity is separated by much longer periods of relative quiescence that range from 500 to 1000 years, which suggests quasiperiodic earthquake occurrence on sub-segments of the Pazarc & imath;k segment. Our fault-parallel trenches revealed 101 +/- 5 m offset in the last 18 kyr and 51 +/- 1 m offset in the last 9 kyr on a buried stream channel and the actual channel of the same stream respectively. The correlation of the maximum and abandonment age of the channel with measured offsets revealed a 5.6 mm a(-1) long-term slip rate of the fault.