1. High‐Resolution Broadband Lg Attenuation Structure of the Anatolian Crust and Its Implications for Mantle Upwelling and Plateau Uplift.
- Author
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Zhu, Wei‐Mou, Zhao, Lian‐Feng, Xie, Xiao‐Bi, He, Xi, Zhang, Lei, and Yao, Zhen‐Xing
- Subjects
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SEISMIC wave velocity , *SUBDUCTION , *SLABS (Structural geology) , *TEMPERATURE measuring instruments , *CENOZOIC Era - Abstract
The Anatolian Plateau, currently experiencing rapid uplift and westward escape, records both the termination of oceanic subduction and the conversion to continental collision. The crustal response to the transition of the subduction environment from eastern to western Anatolia can be inferred by the seismic velocity and attenuation structures. With this study, we construct a broadband Lg‐wave attenuation model for the Anatolian Plateau and use it to constrain lateral crust heterogeneities linked to this transition. Crustal Lg attenuation links late Cenozoic magmatism with asthenospheric upwelling by characterizing the lithospheric thermal structure. The widely distributed strong attenuation observed in eastern Anatolia may be related to the crustal partial melting due to mantle upwelling after the delamination and subsequent break‐off of the Bitlis slab. Lithospheric dripping in central Anatolia likely facilitates the mantle flows through the window between the Cyprus and Aegean slabs, which results in the piecemeal low QLg ${Q}_{\mathit{Lg}}$ anomaly in central Anatolia. Plain Language Summary: Different parts of the Anatolian Plateau are in different evolution stages between oceanic subduction and continental collision and currently undergoing plateau uplift and tectonic escape. The regional seismic velocity and attenuation can be used to characterize crustal partial melting and lateral heterogeneity, which can further identify the underlying subduction process. In this study, we construct a high‐resolution broadband Lg‐wave attenuation model for the Anatolian Plateau. Strong Lg attenuation in Anatolia correlates well with late Cenozoic magmatism distributions and can be an indicator of high temperature or partial melting in the crust. Combined with previous studies, we suggest that the mantle upwelling induced by the delamination of the Bitlis slab is likely reworking the crust in eastern Anatolia and is the cause of widespread thermal anomalies there. The lithospheric dripping process in central Anatolia may facilitate the mantle flows through the window between the Cyprus and Aegean slabs, and results in a piecemeal low QLg ${Q}_{\mathit{Lg}}$ anomaly pattern in central Anatolia. Key Points: A high‐resolution broadband Lg‐wave attenuation model is constructed for the Anatolian PlateauWidespread strong attenuation in the eastern Anatolian crust is likely related to slab delaminationThe circular‐shaped attenuation anomaly may result from slab tearing and lithospheric dripping beneath central Anatolia [ABSTRACT FROM AUTHOR]
- Published
- 2023
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