A Robust Attention-Based Time-Gated LSTM for Change Point Detection in Challenging InSAR Time Series with Data Gaps
摘要
Detecting kinematic transitions, often termed trend changes, in Interferometric Synthetic Aperture Radar (InSAR) derived displacement time series is a critical task for geophysical hazard monitoring. This process is frequently impeded by nonlinear deformation patterns, irregular sampling, and significant temporal data gaps. To address this challenge, we introduce an Attention-based Time-Gated Long Short-Term Memory (ATGLSTM) architecture that synergistically integrates temporal gating with a self-attention mechanism to enhance Change Point Detection (CPD), specifically under conditions of data sparsity. The proposed architecture was rigorously trained and evaluated using a combination of realistic synthetic time series, calibrated with European Ground Motion Service (EGMS) data, and real-world observations from the geodynamically complex and data-sparse region of Iceland. Benchmarked against a conventional Convolutional Neural Network (CNN) and a standard Time-Gated LSTM (TGLSTM), the ATGLSTM demonstrated superior performance, achieving an F1-score of 82.40% on simulated data and 72.24% on a manually annotated real-world dataset. These results establish the ATGLSTM as a robust and scalable tool for automated deformation monitoring, holding significant potential for improved hazard assessment and geophysical investigations where SAR observations are discontinuous.