Determination of relative tectonic activity of the Honaz fault (SW Turkey) using geomorphic indices

Abstract

In this study, in order to determine relative tectonic activity of the Honaz Fault, geomorphic indices such as triangular facets, drainage basin asymmetry (AF), hypsometric integral (HI), drainage basin shape (Bs), ratio of valley-floor width to valley height (Vf), and mountain front sinuosity (Smf) have been calculated. The results of the indice analysis were evaluated and then index of the relative tectonic activity (Iat) were re-evaluated. Base on the different Iat values, the results were divided into four classes that range from the relatively highest to the relatively lowest tectonic activity. The drainage basin area between Honaz Fault and Mount Honaz is an ideal place to test relative tectonic activity. The Honaz fault that is the north boundary fault of the Honaz Mountain has been divided into the Karateke segment and Honaz segment. The indice values calculated from these segments are triangular facets (Lf/Ls: 0.3-0.46), AF (32-77), HI (0.1-0.6), Vf (0.08-0.7), Bs (1.53-5.06) and Smf (1.12-1.41). The results of this study exhibit the presence of high to very high tectonic activity especially in the central part of the Honaz Fault. Based the results, the neotectonics played an important role in geomorphic evolution of this part of the Honaz Mountain. In addition to the results obtained, evidence of seismic activity, travertine occurrences due to thermal springs and alluvial fans in front of fault zones support high tectonic activity in the region.