A preliminary microzonation study on Northern Coasts of Izmir: Investigation of the local soil conditions

In this paper, distribution of the dynamic soil properties in a region comprising the majority of the Izmir Karşıyaka municipality borders is investigated. A number of geotechnical and geological parameters of the region, which involve the results of formerly and recently drilled borings as well as the results of the geotechnical tests performed on undisturbed specimens are considered. Moreover, collected data, and the variation of dynamic soil properties in the region is demonstrated utilizing a Geographical Information System (GIS) software, in which a square grid of 250 m cell size is determined. The variation of the average shear wave velocities in the upper 30 m of the region as well as the soil classes among NEHRP are thematically investigated to determine the variation of soil properties in the region, which may be triggered by high water table at alluvial areas. Simulated ground motions are created using a scenario earthquake on active İzmir fault of 6.9 magnitude, having an average distance of 10 km to the region under investigation. As a consequence, these motions are utilized to map the distribution of maximum spectral amplifications, maximum surface spectral accelerations as well as the ground shaking maps, for a better understanding of the risk in the region.

► Distribution of the dynamic properties of soils underlying northern Izmir is investigated.
► Dominant NEHRP soil class is Class D, however, area of E-F class soils should not be disregarded.
► The ground shaking map can be taken as a supplementary document in urban renewal planning.