Catalogue of Very Low Frequency Events in Mayotte (May 2018–January 2022)

Schema (columns) - station_code: code of the station used for detection, in the format Network.Station.Location.Channel - eventid: Unique event identifier (YYYYMMDD_HHMMSS) - starttime: Event start time (ISO 8601, UTC) - endtime: Event end time (ISO 8601, UTC) - duration_s: Event duration in seconds (float) - amax: Peak amplitude of the VLF signal (instrument units) - snr: Signal-to-noise ratio (dimensionless) - period_s: Dominant period (seconds) of the VLF waveform for the event - energy: Integrated signal energy (instrument units squared) - period_mean_s: Mean period estimate (seconds) - period_std_s: Standard deviation of the period estimate (seconds) - humps: Count of humps/peaks in the VLF envelope (integer) - t0_s: Model fit window bound or characteristic time (seconds relative to analysis reference) - t1_s: Model fit window bound or characteristic time (seconds relative to analysis reference) - decay_s: Exponential decay constant from envelope fitting (seconds) - baseline: Estimated baseline level prior to event (instrument units) - scale: Scaling parameter used in the event model fit (dimensionless) - origin_time: Estimated event origin time from location procedure (ISO 8601, UTC) - latitude: Estimated event latitude (decimal degrees) - longitude: Estimated event longitude (decimal degrees) - depth_km: Estimated event depth (kilometres) Note that the last four columns (origin_time, latitude, longitude, depth_km) are only included if the event was successfully located.

See the Related Publication (Laurent et al., 2025) for information on how the catalogue was built.