Reproducible Python workflows for aircraft Doppler signals, seismic event spectrograms, and aircraft-event overlap analysis using dense nodal seismic arrays.
This repository contains research scripts for analyzing aircraft-generated seismic signals and seismic events recorded by dense nodal arrays. The workflows are currently organized around aircraft crossing analysis, Doppler-curve interpretation, spectrogram generation, event-arrival overlays, and aircraft-event overlap diagnostics.
The current motivation is the analysis of the Denali nodal array deployment, but the workflow is designed so that the same ideas can be adapted to other dense seismic arrays and source-classification problems.
Dense nodal arrays can record multiple signal sources in the same time window, including aircraft, earthquakes, glacial events, explosions, and unknown events. Aircraft often produce Doppler-modulated spectral curves, while seismic events produce arrival patterns that may overlap with aircraft signals. This repository provides tools to inspect, separate, and interpret these sources using waveform processing, aircraft geometry, event catalogs, Doppler physics, and statistical diagnostics.
Aircrafts_Events_Analysis/
├── aircrafts/
│ └── aircraft crossing, Doppler, flight-path, and unknown-aircraft analysis
├── events/
│ └── earthquake, glacial, explosion, and unknown-event analysis
├── plotting/
│ └── plotting and summary figure scripts
├── utilities/
│ └── helper scripts, diagnostics, audits, and data checks
├── figures/
│ └── selected example figures
├── data_examples/
│ └── small example input formats or schema notes
├── requirements.txt
├── .gitignore
└── README.md
Main workflows
Aircraft analysis
The aircraft workflow includes tools for aircraft crossing statistics, flight-path plotting, Doppler visibility modeling, multi-aircraft Doppler scoring, and unknown aircraft-type inference. Unknown aircraft are compared with known jets, propeller aircraft, and helicopters using physical and Doppler-related features such as speed, altitude, slant distance, predicted Doppler sweep, and central Doppler slope.
Event analysis
The event workflow includes tools for earthquake, glacial, explosion, and unknown-event spectrograms. These scripts support event-centered waveform windows, event-arrival overlays, local/regional/global event selection, and event-aircraft overlap analysis.
Spectrogram generation
The spectrogram workflow generates seismic spectrograms for aircraft crossings, event windows, and overlap windows. These products are used to inspect Doppler curves, seismic arrivals, and ambiguous multi-source time windows.
Plotting and summary figures
The plotting workflow creates spatial maps, flight-path plots, aircraft-type summaries, statistical feature plots, Doppler theory figures, and diagnostic figures.
Typical inputs
Most scripts require local data paths. Typical inputs include:
Station metadata
Aircraft crossing database
Flight trajectory files
Waveform files
Earthquake or event catalogs
Arrival-time tables
Aircraft metadata tables
Large waveform files, full spectrogram output folders, and complete local datasets are not stored in this repository.
Typical outputs
Typical outputs include:
Aircraft crossing summaries
Flight-path figures
Event-centered spectrograms
Aircraft-event overlap spectrograms
Doppler scoring figures
Unknown-aircraft classification figures
Summary CSV files
Publication-style diagnostic plots
Reproducibility notes
For each analysis run, record the input crossing file, station metadata file, waveform directory, event catalog, date range, station or node selection, crossing radius, spectrogram parameters, filtering choices, and output directory.
Status
This repository is actively being developed for research analysis. Some scripts are currently standalone workflows. Over time, shared utilities for path handling, spectrogram configuration, plotting style, and catalog readers may be added.