Code and Data for "Resolving sub-kilometer cascading ruptures of moderate earthquakes with Distributed Acoustic Sensing"

Earthquake back-projection (BP) with DAS arrays using an EGF-based iterative stripping approach Repository Structure The code in this repository is organized into three primary folders: 1. S1_ARF_mapT The code in this directory illustrates how to calculate the Array Response Function (ARF) and quantify back-projection uncertainty. Channel Data: The das_info subfolder contains channel locations for five distinct DAS arrays. Among these, array0 represents the actual Ridgecrest DAS array, while the remaining entries correspond to other telecommunication cables used for comparison. Computation: Run get_ARFs_xyt.py to calculate the ARF for all grid points. Setting das_used = [0] will utilize only the real Ridgecrest DAS array (Figure 1A). Setting das_used = [0, 1, 2, 3, 4] will utilize all five arrays (Figure 1B). Visualization: Use the Jupyter Notebook analyze_ARF.ipynb to visualize and analyze the calculated ARFs. 2. S2_Synthetic_Test The code in this directory illustrates how to construct a synthetic earthquake source and perform back-projection analysis. The DAS waveform can be found in Data.zip Pre-processing Steps: Before running the back-projection, execute build_timetable.py and get_ARF.py. These scripts generate the theoretical travel-time tables and the "shadow zone" geometry required for the BP algorithm. Analysis: Running the Jupyter Notebook syn_bp.ipynb will perform the synthetic back-projection and generate all associated figures. 3. S3_Barstow_BPThis directory contains the code for the back-projection analysis of the 2024 Mw 4.9 Barstow earthquake. As with the previous section, the required DAS waveform can be found in Data.zip. Pre-processing Steps: Before running the analysis, execute build_timetable.py and get_ARF.py. These scripts generate the theoretical travel-time tables and the "shadow zone" geometry required for the BP algorithm. Analysis: Running the Jupyter Notebook bp_cross_egf.ipynb to do validation between two EGF events; running the Jupyter Notebook bp_stripping.ipynb to do back-projection.