Keywords:

Türkiye is under the effect of major continental strike-slip fault systems (NAFZ-EAFZ), which have been developed by the movement of the African and Arabian plates towards Eurasian plate. The East Anatolian Fault Zone (EAFZ) is divided into several branches after Çelikhan. It has an E-W trend towards Göksün and south of this line it consists of numerous segments parallel to the general strike of the EAFZ, which cuts the Çukurova basin. One of these lines, approximately 172km long fault zone starting from the northwest of Kahramanmaraş and entering into the sea at Karataş, was identified as the Alahanlı Fault Zone, which has clear evidence about its geometry and kinematic near Alahanlı Village (Sakızgediği). This part of the fault zone is consisting of several segments with en echelon and branched sections. In this study, 73 km part of this zone extending between the east of Aslantaş Dam and Yumurtalık, has been studied. Field data have been obtained in the middle part of the Alahanlı Fault Zone that reveals the segment structure and activity of the left lateral strike-slip fault with a reverse slip component between Sarpınağzı Village and Delihalil Tepe in Sarpınağzı village, Küçükser hill volcanic cone, Toprak hill in the Alahanlı Village NW, quarry locality in the north of Dede hill, and the Delihalil hill volcanic cone. In addition, paleoseismological studies were carried out in two trenches excavated on the main line of fault in the south of Alahanli and from Cevdetiye, on the strand of the fault separating from the main line and crossing over Alahanlı and bending to the E in the direction of Toprakkale and reaching the Kısık Boğazı. In both trenches, at least three earthquakes are recorded, which caused a 12 m wide deformation zone and created surface ruptures in the 1 m thick Holocene aged slope debris, muddy and paleosoil horizons. Another important data showing the activity of the Alahanlı Fault Zone is the three distinct remains of the ancient settlement on slopes of the Delihalil hill volcanic cone, which the fault crosses. According to the archaeological studies, the beginning of life is dated to the 5th century BC, and the absence of cultural material related to the life after the end of the 6th century and the damage in the ancient buildings reveal a devastating earthquake.

Anahtar Kelimeler: Alahanlı Fault Zone, Paleoseismology, Tectonic, Earthquake