杜苛,李红谊,李炎臻,黄雅芬. 2023. 紫坪铺水库及邻区的微震检测与定位. 地震学报,45(0):1−15. doi: 10.11939/jass.20230008
引用本文: 杜苛,李红谊,李炎臻,黄雅芬. 2023. 紫坪铺水库及邻区的微震检测与定位. 地震学报,45(0):1−15. doi: 10.11939/jass.20230008
Du K,Li H Y,Li Y Z,Huang Y F. 2023. Microseismic detection and location around the Zipingpu reservoir and its adjacent area. Acta Seismologica Sinica45(0):1−15. doi: 10.11939/jass.20230008
Citation: Du K,Li H Y,Li Y Z,Huang Y F. 2023. Microseismic detection and location around the Zipingpu reservoir and its adjacent area. Acta Seismologica Sinica45(0):1−15. doi: 10.11939/jass.20230008

紫坪铺水库及邻区的微震检测与定位

Microseismic detection and location around the Zipingpu reservoir and its adjacent area

  • 摘要: 本文首先对四川省地震局提供的1 017个地震进行重定位,并将重定位后的578个高信噪比地震作为模板,利用基于图像处理器加速的匹配定位技术(GPU-M&L)对紫坪铺水库地震台网7个台站记录的2005—2008年连续波形数据进行扫描,然后通过利用基于深度学习算法的去噪技术(DeepDenoiser)设计了一个卷积神经网络模型来进一步验证这些新检测到的地震事件,最后利用双差定位法对检测到的地震事件进行精定位。最终识别到的地震事件多达16 836个,约为四川省地震局目录事件的13倍,完备震级由目录的ML1.4降为ML−0.1,定位结果显示研究区的地震事件呈北东向线性分布,优势震源深度指示区域地壳内的滑脱层位置,结合b值和震源深度分析结果推测研究区蓄水后的地震主要是构造应力积累导致的天然地震活动,并伴随水库触发地震混杂发生。

     

    Abstract: Firstly, 1 017 earthquakes provided by Sichuan Seismological Bureau are relocated, and 578 earthquakes with high signal-to-noise ratios after relocation are used as templates. The continuous waveform data recorded by 7 stations of Zipingpu reservoir seismic network from 2005 to 2008 are scanned by GPU-based match and locate (GPU-M&L) method. Then, based on the denoising results by applying the deep learning algorithm called DeepDenoiser, a convolutional neural network model is designed to further verify these newly detected events. Finally, the double-difference location method is used to accurately relocate them. A total of 16, 836 events are eventually identified, which is about 13 times as many as the events listed in the local catalog. The magnitude of completeness is reduced from ML1.4 given by the local catalog to ML−0.1. The relocated results show that the seismic events in the study area are linearly distributed in the northeast direction. The dominant focal depth indicates the location of the detachment layer in the crust of the region. Combined with the analysis results of b value and the focal depth, it is speculated that the earthquakes after impoundment in the study area are mainly natural seismic activities caused by the accumulation of tectonic stress, accompanied by the occurrence of reservoir-triggered seismicity.

     

/

返回文章
返回