Multi-method geophysical investigation for subsurface characterization: A case study from the Kocaeli-Karamürsel Çamdibi Region, Türkiye
JOURNAL OF AFRICAN EARTH SCIENCES, cilt.242, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 242
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.jafrearsci.2026.106236
- Dergi Adı: JOURNAL OF AFRICAN EARTH SCIENCES
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Geobase, INSPEC, Zoological Record
- Kocaeli Üniversitesi Adresli: Evet
Özet
Accurate characterization of near-surface conditions is essential for seismic risk assessment in tectonically active areas, where fault-controlled lateral heterogeneity strongly influences site response. This study presents a comparative multi-method geophysical interpretation approach for seismic microzonation in the Kocaeli-Karam & uuml;rsel & Ccedil;amdibi region (NW T & uuml;rkiye), combining electrical resistivity tomography (ERT), multichannel analysis of surface waves (MASW), single-station microtremor measurements, and borehole data. The aim is to characterize fault-controlled lateral heterogeneity and assess its influence on seismic vulnerability through the interpretation of geoelectrical structure, shear-wave velocity, and HVSR-derived site-response parameters. ERT imaging revealed laterally disrupted resistivity layering across the & Ccedil;amdibi Fault, consistent with lithological offsets observed in boreholes. MASW dispersion-curve inversion resolved the shear-wave velocity structure and identified two distinct stiffness domains representing contrasting ground conditions. Horizontal-to-vertical spectral ratio (HVSR) results from 19 stations indicated significant spatial variability in dominant frequency and amplification, from which a seismic vulnerability index was estimated. A pronounced high-vulnerability zone was identified in the central-southern sector, whereas relatively lower vulnerability values were observed near the fault zone, consistent with the MASW-derived stiffness variations and ERT-defined structural boundaries. These results indicate that fault-controlled lateral heterogeneity is consistently expressed across the ERT, MASW, HVSR, and borehole datasets, and that the inferred structural and stiffness contrasts correspond spatially with variations in resonance and amplification. The study establishes a borehole-supported, engineering-oriented microzonation framework based on comparative interpretation of multiple geophysical datasets, enabling improved delineation of site-response variability in structurally complex terrains.