10 Ağustos 2025 Mw 6.1 Sındırgı (Balıkesir) Depremi Sırasında Gözlenen Jeomanyetik Alan Değişimleri

Öz

Batı Anadolu, aktif normal faylarla karakterize edilen genişlemeli bir tektonik rejime sahiptir. Bu çalışmada, 10 Ağustos 2025 tarihinde Balıkesir-Sındırgı yakınlarında meydana gelen Mw 6.1 büyüklüğündeki depremin eş-sismik jeomanyetik etkileri incelenmiştir. İznik (IZN) jeomanyetik gözlemevine ait 1 saniyelik H, D ve Z bileşenleri ile AFAD 1657 istasyonunun ivme kayıtları birlikte analiz edilmiştir. Ana şok sırasında tüm jeomanyetik bileşenlerde kısa süreli anomaliler belirlenmiştir. Genlik zarfı analizleri, enerji yoğunlaşmasının ilk yaklaşık 60 saniye içinde gerçekleştiğini göstermektedir. Manyetik piklerin, P ve S dalga varışları ile maksimum ivme değerleriyle zamansal uyumlu olduğu saptanmıştır. Kp, Hp30 ve SYM-H indeksleri jeomanyetik fırtına olmadığını göstermektedir. Sonuçlar, sinyallerin kabuksal elektromanyetik üretimden çok aletsel kaynaklı olabileceğini ortaya koymaktadır.

Anahtar Kelimeler

• Batı Anadolu
• Sındırgı depremi
• Eş-sismik jeomanyetik değişim
• Jeomanyetik alan
• Aletsel yanıt

Geomagnetic Field Perturbations Observed During the 10 August 2025 Mw 6.1 Sındırgı (Balıkesir) Earthquake

Öz

Western Anatolia is characterized by an extensional tectonic regime dominated by active normal fault systems. In this study, the co-seismic geomagnetic effects of the Mw 6.1 earthquake that occurred near Balıkesir-Sındırgı on 10 August 2025 were investigated. One-second resolution H, D, and Z components from the İznik (IZN) geomagnetic observatory were analyzed together with acceleration records from the AFAD 1657 station. During the main shock, transient anomalies were identified in all geomagnetic components. Envelope analyses indicate that the maximum energy concentration occurred within the first approximately 60 seconds. The magnetic peaks were found to be temporally consistent with the arrivals of P and S waves and the peak ground acceleration values. The Kp, Hp30, and SYM-H indices indicate the absence of a geomagnetic storm. The results suggest that the observed signals reflect an instrumental response to strong ground motion rather than crustal electromagnetic generation.

Anahtar Kelimeler

• Western Anatolia
• Sındırgı earthquake
• Coseismic geomagnetic perturbations
• Geomagnetic field
• Instrumental response

Kaynakça

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