**6. Conclusion**

28 Earthquake Research and Analysis – Seismology, Seismotectonic and Earthquake Geology

Fig. 6. Dish and pillar structures occured by the movement of pore water in sediments.

Fig. 7. Deformation structures observed among the undeformed parallel layers at different

levels.

In this study, the shapes, dimensions and locations of soft sediment deformation structures and facies properties and depositional environments of Quaternary aged lacustrine deposits of Lake Van are investigated. According to these features, deformation structures are classified into three parts as contorted structures, load structures and water escape structures.

Earthquake records show the tectonic activity (M≥5) of Lake Van and surrounding area. This data suggest that, the earthquakes should effect the lacustrine deposits in time of deposition (Late Quaternary). The deformation structures are frequently observed in different levels of lacustrine deposits. These deformed layers are the evidence of the repeated tectonic activity (M≥5) that effect the Lake Van deposits.

The relationship between the earthquake moment magnitude and the distance from epicenter to liquefaction locations appeal to the geologists. This distance may be more than 100 km in big earthquakes (M>7). According to locations and the distribution of soft sediment deformation structures, these structures should be formed by more than one faults activities.
