oa Telceker Landslides; Mass Flow Morphology and Seismotectonic Influences on Hazard Mitigation. Dogubayazit. Agri, Eastern Turkey

Landslides, volcanic debris and mud flows are the most frequently occurred common geohazards in the Region of Great Ararat Volcano. Most geohazards are triggered or re-activated by earthquakes. This Region well known in literature as Turk-Iran High Volcanic Plateau (TIHVP) which located in front of Arabian-Eurasian Collision Suture. High seismicity and high relief due to young volcanism influenced mass movements. Landslides are frequently triggered by seismic shocks and developed by decreased slope stability due to active fault displacements. Telceker Landslide has been studied first by remote sensing and near surface geophysical techniques, by a joint research team from US-Los Alamos National Laboratory. Detailed geology, morphotectonic features and active tectonics of a landslide and surrounding area were studied. Telceker landslide subsidence started at the Turk-Iran border, water-divide line. Collapsed debris flowed northwards down along the valley and deposited near Telçeker Village at Doğubayazit Plain. The dominant character of the landslide mass is dominantly debris flow and currently active Mud Flow, at upper stages. The western margin is defined by a north-northeast striking left slip oblique Maşer Fault. Several ponds, swamp areas, longitudinal ridges, and transversal cracks, concave scarp structures have formed. Three segments of landslide are distinctly recognized along flow-direction. At the center, a Mud Flow continues through a narrow channel-like corridore, leaving lens-shaped huge fragments behind at the entrance to the corridor, 350 m wide and approximately 2.0 km long. A third segment is represented by deposition-accumulation of debris at the foot (toe) which crosses the Doğubeyazit Fault scarp where turns East (at sharp angle) resulted by right lateral displacement of the DB fault zone. Coarse debris spread down into the Doğubeyazit Plain in a fan-like geometry due to the high slope angle. Three stages of landslide activity are recongized, particularly at the lower part of corridor and at foot area. These stages are recognized by ground data based on textureal difference in topography, morphology, and degree of consolidation.