基于格拉姆角场和多尺度残差神经网络的地震事件分类方法

Seismic events classification based on Gram’s angle field and multi-scale residual neural network

  • 摘要: 以江苏地震台网中心搜集并标注的天然地震、人工爆破和塌陷事件为试验数据样本,提出了一种基于格拉姆角场和多尺度残差神经网络的新的地震事件分类方法。首先对波形数据进行滤波、归一化等预处理,然后应用格拉姆角场对地震波形数据进行二维编码得到二维图像,再将此经过编码后的图像作为多尺度残差神经网络的输入进行分类模型的训练和测试,从而得出分类结果。采用上述方法对1 078个天然地震台站记录、981个爆破台站记录和830个塌陷台站记录进行试验,结果显示:最终以单条波形为单位的地震事件分类准确率为92.55%,以单个台站为单位的分类准确率为96.36%,这表明基于格拉姆角场和多尺度残差神经网络的地震分类方法具有良好的效果。

     

    Abstract: The rapid advancement of seismic observation systems has ushered in an era of seismic big data, encompassing both artificial and natural events. This development presents new challenges that necessitates precise seismic event classification to enhance earthquake response strategies and seismological research.   This paper presents a novel approach for classification seismic events, integrating Gram’s angle field (GAF) with a multi-scale residual neural network, designated as QxceptionNet. The GAF method converts seismic wave time series into a graphic representation, preserving the interdependencies among different sampling points. The application of multi-scale convolutional analysis in this context reveals a more detailed feature set within the GAF images. Additionally, the residual structure of networks is designed to prevent performance degradation, even as network depth increases. The synergy of these elements forms the foundation of our proposed methodology.   The approach utilizes a dataset meticulously compiled and labeled by the Jiangsu Earthquake Agency, encompassing station records of natural earthquakes, artificial blasts, and collapses. Each record consists of three-channel waveforms. As an initial step, the raw seismic waveforms are normalized in amplitude, linearly detrended, and filtered to reduce effects from the recording instruments. To maintain consistency, all waveforms are truncated to a standardized length of 40 seconds. Subsequently, those waveforms are transformed into GAF images. These images, along with their respective category labels, serve as inputs for the QxceptionNet. The network’s training results in outputting probabilities, categorizing the waveform data into one of the three seismic event types. Our results indicate impressive classification accuracies across various seismic event categories, emphasizing the efficacy of this approach in seismic classification. The test results show that the accuracy for 1 078 natural seismic event records, 981 blast records, and 830 collapse records are 92.55% for classifications based on individual waveform records and 96.36% for those based on single station records. Notably, these accuracies surpass those achieved by other methods, such as support vector machine (SVM), multi-layer perceptron (MLP) and short-time Fourier transform (STFT) combined with convolutional neural network (CNN). These findings suggest that the combined use of the Gram’s angle field and multi-scale residual neural networks is highly effective in distinguishing different types of seismic events.  In summary, this paper elucidates the process of transforming seismic waveform data into GAF images, the architectural design of the network model, and the comprehensive experimental setup and results. Looking ahead, broadening the scope of the classification system to encompass a more diverse array of seismic occurrences and integrating a wider variety of samples will be essential in creating an all-encompassing and intelligent seismic event detection system.

     

/

返回文章
返回