青藏高原中强地震InSAR震源参数反演及其与地震目录的比较

Source Parameter Inversion of Moderate to Strong Earthquakes and Its Comparison with Earthquake Catalogs in Tibetan Plateau based on InSAR Observations

  • 摘要: 合成孔径雷达干涉测量技术(Interferometric Synthetic Aperture Radar, InSAR)具有高空间分辨率和高形变监测精度的特点,为研究浅源中强震级地震的震源机制提供了有力约束。该研究采用 InSAR相位堆叠和贝叶斯反演方法构建了 2014年 10月至 2022年 10月发生在青藏高原的 42次中强震级(Mw 4.8~6.6)地震的震源参数目录,探讨其与地震目录的差异。结果显示,与通用地震目录确定的地震质心深度相比, InSAR深度定位结果更浅;全球质心矩张量(Global Centroid Moment Tensor, GCMT)目录的震中位置存在系统性偏差; InSAR反演结果能够更精细地表达断层的几何形态。该研究结果可更新和完善青藏高原的地震目录,为改进区域经验标度关系提供了重要依据,可服务于区域地震危险性评估。

     

    Abstract: Objectives: Synthetic aperture radar interferometry (InSAR) is capable of high spatial resolution and deformation monitoring accuracy. It can effectively constrain the source parameter of moderate shallow earthquakes. Methods: In this study, using InSAR phase stacking and the Bayesion inversion methods, we construct the source parameters catalog for 42 moderate to strong(Mw 4.8-6.6) earthquakes that occurred in the shallow crust of the Tibetan Plateau from October 2014 to October 2022 . Results: The results demonstrate that the InSAR-derived depth location is shallower than the centroid depth recorded in general seismic catalogs. The location of the epicenter of the Global Centroid Moment Tensor (GCMT) catalog is systematically biased. It also reveals the result of InSAR inversion can express the geometry of fault more precisely. Conclusions: The study shows that the InSAR-derived catalog is a significant supplement to the existing global catalog and can improve empirical scale relationships, facilitating scientific reference for regional seismic risk assessment.

     

/

返回文章
返回