Section outline

  • SUBMERSE (SUBMarine cablEs for ReSearch and Exploration) is an innovative EU-funded project that aims to turn existing submarine telecommunication cables into an international fiber optic sensing network, providing near real-time data flows to monitor the Earth and its systems.

    At the SUBMERSE Community Event in April 2026, this training session explored the scientific potential of a 57-kilometer dark fibre around Madeira, branching off the main cable connecting Brazil and Portugal. Using an OptoDAS interrogator, GeoLab researchers have been collecting data since 2023 at a 500 Hz sampling rate and 10m gauge length. 

    For the practical part of the session, a real sample dataset from October 2023 was downloaded for running a guided analysis on a prepared Colab notebook.


    • Madeira and the GeoLab fibre 3X.2023 dataset File PDF
    • Notebook: the GeoLab fibre and the 3x2023 DAS dataset URL

      Open this Colab notebook to replicate the exercises presented in the video tutorial.

      1. Environment Setup: Installation of obspy, boto3, and simpledas.
      2. Example 0 / S3 Data retrieval: You learn how to connect to a public S3 bucket (GeoLab 3X.2023) using boto3 to download HDF5 DAS data files based on specific time windows.
      3. Example 1 / Data formatting: Demonstrates how to use simpledas to load raw data into a Pandas DataFrame and convert it into an OBSpy Stream object for seismic processing.
      4. Examples 2 and 3 / Manual whale detection: These exercises guide you through signal enhancement using bandpass and F-K (Frequency-Wavenumber) filtering to isolate Blue and Fin whale calls from background noise.
      5. Example 4 / Automated marine mammals detection: You implement a template-matching algorithm using cross-correlation to automatically identify whale vocalisations and generate a detection report and spectrogram.
      6. Example 5 / Coastal geophysics: This exercise shifts focus to oceanographic signals, where you analyse wave dispersion curves in the f-k domain to estimate water depth and the effects of ocean currents.

      How to cite this notebook: Afonso Loureiro (2024): GeoLab. GFZ Data Services. Dataset/DAS. doi:10.14470/8K802502