Geodetic Constraints on Segment-Scale Slip Rates and Interseismic Coupling Along the Havran–Balıkesir Fault Zone, NW Anatolia, Türkiye


Tiryakioğlu İ., Solak H. İ., Özkan A., Gezgin C., Eyübagil E. E., Çakanşimşek Ünlükaya E. B., ...Daha Fazla

Sensors, cilt.26, sa.8, 2026 (SCI-Expanded, Scopus) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 26 Sayı: 8
  • Basım Tarihi: 2026
  • Doi Numarası: 10.3390/s26082539
  • Dergi Adı: Sensors
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Compendex, INSPEC, MEDLINE, Directory of Open Access Journals
  • Anahtar Kelimeler: block modeling, GNSS, Havran–Balıkesir fault zone, interseismic coupling, seismic hazard, slip partitioning
  • Ankara Üniversitesi Adresli: Evet

Özet

This study presents a new high-resolution GNSS-derived velocity field and the first internally consistent, segment-resolved block model for the Havran–Balıkesir Fault Zone (HBFZ) in western Anatolia. Inversion of the GNSS velocity field was performed using a dense network of 77 sites within a 3D elastic half-space framework to estimate fault slip rates and interseismic coupling. The results reveal that the HBFZ behaves as a kinematically heterogeneous fault system, with deformation systematically partitioned along strike. Block-modeling results indicate pronounced along-strike variations in interseismic coupling and slip-deficit accumulation. While the westernmost Havran segment is weakly coupled and accommodates limited accumulation, the Turplu and Gökçeyazı segments emerge as major strain-accumulation zones with high and laterally continuous slip-deficit rates. In particular, the Gökçeyazı segment exhibits slip-deficit rates of ~4–6 mm/yr and nearly two millennia of seismic quiescence, implying the potential for a future large-magnitude earthquake (Mw ~7.1–7.3). The strong agreement between GNSS-derived deformation patterns and independent geological and paleoseismological constraints suggests that this segment is currently in an advanced stage of the seismic cycle. These findings highlight the importance of segment-scale geodetic observations for seismic hazard assessment in northwestern Anatolia.