Western Anatolia Crust Deformation Modelling: An Evaluation Based on GPS and Seismic Data

Öz

Western Anatolia represents a complex region influenced by diverse tectonic regimes and deformation processes. This study integrates GPS velocity data and seismic analyses to investigate the deformation dynamics of the region comprehensively. High effective strain rates (~140 nanostrain/year) along the North Anatolian Fault Zone (NAFZ) highlight compressional regimes, while positive dilation rates (+50 nanostrain/year) in the Aegean extension zone emphasize crustal thinning under extensional forces. These findings directly address the study’s primary aim of identifying the active tectonic framework of Western Anatolia and assessing seismic hazards in the region. Seismic analysis further underscores the influence of significant earthquakes on regional deformation, revealing compressional dominance in the eastern Marmara Sea and extensional regimes in its western segments. The integration of GPS velocity fields and dilation maps delineates the spatial distribution of energy accumulation and crustal thinning across Western Anatolia. These results provide a scientific basis for identifying high-seismic-risk areas and developing risk mitigation strategies. This comprehensive analysis of deformation processes offers critical insights into seismic hazard assessment and risk reduction strategies for Western Anatolia.

Anahtar Kelimeler

• Western Anatolia
• Crustal Deformation
• GPS and Seismic Data
• North Anatolian Fault
• Aegean Extension Regime

Proje Numarası

İzmir Bakırçay Üniversitesi Kariyer Başlangıç Destek Projeleri (KBP) KBP.2021.007

Batı Anadolu Kabuk Deformasyon Modellemesi: GPS ve Depremsellik Verilerine Dayalı Bir Değerlendirme

Öz

Batı Anadolu, farklı tektonik rejimlerin ve deformasyon süreçlerinin etkisi altında bulunan karmaşık bir bölgedir. Bu çalışma, GPS verileri ve depremsellik analizlerini entegre ederek bölgenin deformasyon dinamiklerini detaylı bir şekilde incelemektedir. Çalışmada, Kuzey Anadolu Fay Zonu (KAFZ) boyunca ölçülen yüksek efektif gerinim oranlarının (~140 ngerinim/yıl) sıkışmalı rejimi yansıttığı, buna karşın Ege genişleme bölgesindeki pozitif dilatasyon oranlarının (+50 ngerinim/yıl) genişlemeli rejimin baskın olduğunu gösterdiği tespit edilmiştir. Bu bulgular, çalışmanın temel amacı olan Batı Anadolu’nun aktif tektonik yapısını belirleme ve bölgedeki sismotektonik riskleri değerlendirme hedefine doğrudan katkıda bulunmaktadır. Deprem analizleri, büyük depremlerin bölgesel deformasyon üzerindeki etkisini anlamak için kritik veriler sağlamış; Marmara Denizi doğusunda sıkışmalı, batısında ise genişlemeli rejimlerin hâkim olduğu belirlenmiştir. GPS hız vektörleri ve dilatasyon haritaları, enerji birikimi ve kabuk incelmesi süreçlerinin mekânsal dağılımını ayrıntılı olarak ortaya koymuştur. Bu sonuçlar, yüksek sismik risk taşıyan bölgelerin belirlenmesine ve risk azaltma stratejilerinin geliştirilmesine bilimsel bir temel oluşturmaktadır. Batı Anadolu'nun deformasyon süreçleri üzerine yapılan bu analizler, bölgesel sismik tehlikelerin azaltılması için kritik bir zemin sunmaktadır.

Anahtar Kelimeler

• Batı Anadolu
• Kabuk Deformasyonu
• GPS ve Sismik Veriler
• Kuzey Anadolu Fayı
• Ege Açılma Rejimi

Destekleyen Kurum

İzmir Bakırçay Üniversitesi

Proje Numarası

İzmir Bakırçay Üniversitesi Kariyer Başlangıç Destek Projeleri (KBP) KBP.2021.007

Etik Beyan

Etik Kurul Onayına gerek yoktur.

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