29 Temmuz 2021 Mw=8.2 Chignik, Alaska Peninsula depremi deformasyonlarının bağıl konum belirleme servis sonuçları ile incelenmesi

Öz

Bu çalışmada internet tabanlı bağıl konumlama GNSS veri değerlendirme servislerinin kullanımının IGS ağında koordinat değerleri açısından istatistiksel olarak karşılaştırılması amaçlanmıştır. Bu amaçla, 29 Temmuz 2021’de Alaska’da Mw=8.2 büyüklüğünde gerçekleşen deprem ele alınmıştır. Depremin meydana geldiği Alaska-Aleut bölgesinde yer alan 8 IGS istasyonu seçilmiştir. Bu istasyonların deprem gününü de içeren 15 günlük zaman serileri AUSPOS ve OPUS internet tabanlı GNSS veri değerlendirme servislerinden elde edilen koordinatlar kullanılarak elde edilmiştir. Depremin gerçekleştiği noktaya yakın olan istasyonlarda yatayda 40 cm’ye; düşeyde ise 10 cm’ye varan deformasyon büyüklükleri elde edilmiştir. Her iki servisten elde edilen toposentrik koordinat bileşenlerindeki farkların dağılımı sıfır etrafında toplanırken; en büyük farklar kuzey-güney, doğu-batı ve yükseklik bileşenleri için sırasıyla yaklaşık 5 cm; 7 cm ve 2.5 cm’dir. Söz konusu bu farkların istatistiksel olarak anlamlı olup olmadığını belirlemek için istatistiksel test uygulanmıştır. Test sonucunda, internet tabanlı servislerden elde edilen toposentrik koordinat bileşenleri arasındaki farkların anlamsız olduğu bulunmuştur.

Anahtar Kelimeler

• GNSS
• Deprem
• Bağıl Konum Belirleme
• Doğruluk
• Anlamlılık Testi

Investigating the results of relative GNSS services with the July 29, 2021 Mw 8.2 Chignik, Alaska Peninsula earthquake

Öz

In this study, we aimed to perform a statistical comparison of web-based relative positioning GNSS data processing services concerning coordinate values within the IGS network. To achieve this goal, we focused on the earthquake that struck Alaska on July 29, 2021, with a magnitude of Mw=8.2. We selected 8 IGS stations located in the Alaska-Aleut region, where the earthquake occurred. We used the AUSPOS and OPUS web-based GNSS data processing services to obtain 15-day time series, including the day of the earthquake. At stations near the earthquake's epicenter, we observed horizontal deformations of up to 40 cm and vertical deformations of 10 cm. The distribution of differences in the topocentric coordinate components obtained from both services predominantly centered around zero. However, the substantial differences were approximately 5 cm for the north-south component, 7 cm for the east-west component, and 2.5 cm for the height component. To assess the statistical significance of these differences, we conducted a statistical test. The test results indicate that the differences in the topocentric coordinate components obtained from web-based services are not statistically significant.

Anahtar Kelimeler

• GNSS
• Earthquake
• Relative Point Positioning
• Accuracy
• Significance Test

Kaynakça

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