Tectonic analysis of the Honaz Fault (western Anatolia) using geomorphic indices and the regional implications

Abstract

Honaz Dağı (Honaz Mountain, Denizli) is the highest peak in western Anatolia (2517 m) and represents the southern margin of the Denizli Graben Horst System in the western Anatolia Extensional Province. Honaz Fault is a 2-km-wide, 15-km-long northward arc-shaped dip-slip listric normal fault that bounds the northern margin of Honaz Dağı, and has been formed under an N–S-trending extensional tectonic regime since the early Quaternary. This study uses fieldwork and digital elevation model-based geomorphic analysis to identify the kinematic behaviour of the Honaz Fault. Morphometric indices, such as axial river profiles, drainage basin geometries, triangular facets, mountain‐front lineament patterns and sinuosities, document the impact of active tectonics on the evolution of the Honaz Fault and its surroundings, as do valley floor width-to-height ratios and mountain front facet characteristics. These neotectonic indices suggest a relatively high degree of tectonic activity along the Honaz Fault, and suggest that the Quaternary landscape evolution of Honaz Dağı was governed by structural and climate-related erosional processes. Combined geomorphic indices and field data suggest that the analysed dip-slip normal fault segments of the Honaz Fault are linear and highly active, and could generate earthquakes with magnitudes of 6.7. Morphometric analyses of the fault trace along the mountain front yield minimum slip rates of .15–.38 mm/y for the Honaz Fault, which are similar to slip rates calculated for active normal faults in the Aegean region.