Gravity Tensors and Moho Depth Variations of the Region between West Italy and Eastern of Caspian Sea

Year 2024, Volume: 26 Issue: 77, 218 - 230, 27.05.2024

Fikret Doğru , Oya Pamukçu

https://doi.org/10.21205/deufmd.2024267704

Abstract

The crust structure of the region from the west of Italy to the east of the Caspian Sea was examined within the scope of this study. In addition, the effect of both the shallow and deep structure were revealed by calculating the gravity tensors of the region in different degrees. For this purpose, the spherical free air gravity anomaly of the region was first calculated. The combination of EGM2008 and GOCE DIR R4 models were used for this calculation. Then the gravity tensors of the region were calculated separately using only EGM2008 model and only GOCE DIR R4. The spherical free air anomaly of the region was calculated using the topographic model. The spherical Bouguer anomaly of the region was obtained by subtracting the anomaly obtained from this topographic model from the spherical free air anomaly obtained from GOCE DIR R4 + EGM2008 combined model. The radial averaged power spectrum of the spherical Bouguer anomaly was taken and the anomaly thought to be caused by Moho was filtered out. Moho depth map of the whole region was obtained by applying the Parker-Oldenburg inversion to the filtered anomaly. The obtained values were compared with previous studies and found to be compatible.

Keywords

Tensor, GOCE, EGM2008, Bouguer, Moho

Supporting Institution

Dokuz Eylül Üniversitesi BAP

Project Number

2018.KB.FEN.013

Thanks

This study is funded by Dokuz Eylul University No 2018.KB.FEN.013 Scientific Research Project.

Batı İtalya ile Hazar Denizi Doğusu Arasındaki Bölgenin Gravite Tensörleri ve Moho Derinlik Değişimleri

Abstract

İtalya'nın batısından Hazar Denizi'nin doğusuna kadar olan bölgenin kabuk yapısı bu çalışma kapsamında incelenmiştir. Ayrıca bölgenin farklı derecelerdeki gravite tensörleri hesaplanarak hem sığ hem de derin yapının etkisi ortaya konulmuştur. Bu amaçla öncelikle bölgenin küresel serbest hava gravite anomalisi hesaplanmıştır. Bu hesaplama için EGM2008 ve GOCE DIR R4 modellerinin kombinasyonu kullanılmıştır. Daha sonra sadece EGM2008 modeli ve sadece GOCE DIR R4 modeli kullanılarak bölgenin gravite tensörleri ayrı ayrı hesaplanmıştır. Topografik model kullanılarak bölgenin küresel serbest hava anomalisi hesaplanmıştır. Bu topografik modelden elde edilen anomalinin GOCE DIR R4 + EGM2008 birleşik modelinden elde edilen küresel serbest hava anomalisinden çıkarılmasıyla bölgenin küresel Bouguer anomalisi elde edilmiştir. Küresel Bouguer anomalisinin radyal ortalamalı güç spektrumu alınmış ve Moho'nun neden olduğu düşünülen anomali filtrelenmiştir. Bu Moho'nun neden olduğu düşünülen anomaliye ters çözüm uygulanarak tüm bölgeye ait Moho derinlik haritası elde edilmiştir. Elde edilen değerler önceki çalışmalarla karşılaştırılmış ve uyumlu olduğu görülmüştür.

Keywords

Tensör, GOCE, EGM2008, Bouguer, Moho

Project Number

2018.KB.FEN.013

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