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The seismic hazard for the Lake Van basin is computed using a probabilistic approach, along with the earthquake data from 1907 to present. The spatial distribution of seismic events between the longitudes of 41-45°and the latitudes of 37.5-40°, which encompasses the region, indicates distinct seismic zones. The positions of these zones are well aligned with the known tectonic features such as the Tutak-Ç aldıran fault zone, the Ö zalp fault zone, the Gevaş fault zone, the Bitlis fault zone and Karlıova junction where the North Anatolian fault zone and East Anatolian fault zone meet. These faults are known to have generated major earthquakes which strongly affected cities and towns such as Van, Muş, Bitlis, Ö zalp, Muradiye, Ç aldıran, Erciş, Adilcevaz, Ahlat, Tatvan, Gevaş and Gürpınar. The recurrence intervals of M s C 4 earthquakes were evaluated in order to obtain the parameters of the Gutenberg-Richter measurements for seismic zones. More importantly, iso-acceleration maps of the basin were produced with a grid interval of 0.05 degrees. These maps are developed for 100-and 475-year return periods, utilizing the domestic attenuation relationships. A computer program called Sistehan II was utilized to generate these maps.

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Fissure-ridge travertines (FRTs) are of great importance for the determination and comparison of tectonic deformation in a region. The coeval development of these travertines with active fault zones supplies significant information about regional dynamics in terms of deformation pattern and evolution. In this paper, the characteristics of FRTs of the Başkale basin (eastern Turkey) and responsible regional tectonism are discussed for the first time. The Başkale basin is located between the Başkale Fault Zone (BFZ) characterised by Çamlık fault and Işıklı-Ziraniş fault. It is located between dextral Yüksekova Fault Zone and southern end of dextral Guilato-Siahcheshmeh-Khoy Fault system (Iran). Various morphological features indicating recent activity are exposed along the BFZ, including offsetting rivers, fissure-ridge travertine and fault scarps. The Çamlık fissure-ridge travertine composing of three different depositions is observed along the eastern edge of the BFZ with approximately parallel orientations. The Çamlık fissure-ridge travertine has been formed and developed on fault zone related to strike-slip or oblique movements. We explain how kinematic changes of faults can influence the fissure-ridge development.

The Erciş Fault, which bounds the northern part of the Lake Van Basin, is approximately 50 km long with right‐lateral strike‐slip movement in a N30‐50°W direction. The Erciş Fault starts in the northwest, south of Girekol Volcano, and extends to the Turkey‐Iran border, and together with the Çaldıran Fault forms the tectonic boundary between the Turkey‐Iran Block and Lesser Caucasus‐Talesh Block. Offset riverbeds, fault‐controlled drainage systems, deformed alluvial fans along the faults, Plio‐Quaternary volcanics, and volcanic structures are geomorphic and tectonic features that show that the Erciş Fault is active in the region. This fault has played an active role in the deformation of the Eastern Anatolian Plateau, which developed as a result of collision of the Arabian and Eurasian plates. In this study, the role of the Erciş Fault in the tectonic evolution of the region was investigated using geologic, geomorphologic, and remote sensing analysis methods. According to the morphometric indices used in the study, values of 1 < Smf < 2.1, 0.2 < Vf < 3.29, 0.3 < HI < 0.5, 25 < SL < 850 and 100 < Ksn < 600 were obtained. Results show that the area has an extremely young topography and is actively uplifting. It has been determined that the uplift rate in the region has increased in the northwest and south‐east compared to other areas and is more than 0.5 mm yr−1. According to the remote sensing and field studies, an approximately 850 m right‐lateral offset is observed in the Deliçay River, which is cut by the Erciş Fault, and that the long‐term slip rate of the Erciş Fault is 2.02 ± 0.12 mm yr−1.