Akademik Veri Yönetim Sistemi
76. Türkiye Jeoloji Kurultayı, Ankara, Türkiye, 15 - 19 Nisan 2024, ss.583
In the Bornova Basin, especially in the Bayraklı district, more than
500 buildings were damaged in the Aegean Sea (Samos) earthquake of
30 October 2020. In order to determine the relationship between the
structural damage and the tectonic and soil properties of the basin;
seismic reflection, electrical resistivity tomography (ERT), induced
polarisation tomography (IPT) and spatial auto-correlation (SPAC)
studies were carried out in the basin within the scope of TÜBİTAK
project. Within the framework of these studies; the definition of the
basin boundary faults was analysed by electrical methods, the
sedimentary character of the basin, possible structural discontinuities
and other changes within the basin were investigated by the seismic
reflection method in two perpendicular lines, and the geometry of the
bedrock in the basin and the shear wave velocity distribution of the
sedimentary layers and the bedrock were analysed by the SPAC
method. Based on the seismic data, drilling studies were carried out at
four different locations to determine the sedimentary characteristics of
the layers and the nature of the bedrock under the basin. As a result of
the interpretation of the integrated geophysical data sets and
geological and palaeogeographical studies on the drilling cores,
preliminary information on the geological evolution of the basin was
tried to be obtained. By going deeper than any drilling done in the
basin since the 1950s, the thickness of the sediment and the nature of
the bedrock under the sediment were determined, at least in the part
of the basin where multi-storey construction exists. This has provided
important data on the character of the sedimentary layers in the
densely populated study area. As a result, the general characteristics
of the basin, the characteristics of the sedimentary packages, the basin
boundary faults and the faults within the basin were determined, anda
model of the basin was tried to be established. In this way, answers
were sought to the questions of why the damage caused by this
earthquake remained localised and whether it was due to the basin
effect or other geological problems. In addition, it was seen that the
results provided an important basis for the microzonation studies of
the city of İzmir. The numerical geoscientific data obtained from the
project were transferred to the TÜBİTAK Coordination Project No.
221M169 "Effects of Simulation Based Earthquake Scenarios on
Structural Damage Vulnerability Distribution and Resilient Urban
Planning in Izmir Bornova Basin".
This study was supported by the TÜBİTAK project under grant number
121Y252. This project is an exemplary model of how geoscientific
applications can be carried out in many urban areas of Turkey where
similar problems are observed.