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An interactive web application for exploring and visualising mineral spectral data from the USGS Spectral Library.

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USGS Spectral Library Visualisation Tool

An interactive web application for exploring and visualising material spectral data from the USGS Spectral Library. This tool provides access to both satellite-resampled and full spectrum data with filtering and visualisation capabilities. The app is currently hosted on Posit Cloud.

Features

Dual Data Type Support

  • Satellite Resampled Spectra: Band-specific data for ASTER, Landsat8, Sentinel2, WorldView3
  • Full Spectrum Data: High-resolution spectrometer measurements (BECK, ASD variants, NIC4, AVIRIS)

Advanced Selection & Filtering

  • Multiple material family selection
  • Individual sample selection within selected material families
  • Wavelength range filtering (0.2-25 μm) for full spectrum data
  • Maximum samples per family control

Interactive Visualisations

  • Multi-material spectral plots with band overlays
  • Satellite band response function visualisation
  • Real-time plot updates
  • Customisable display options (band centers, ranges, response functions)

Data Export Capabilities

  • Download plots as high-resolution PNG files (supported by plotly)
  • Export spectral data as CSV files
  • Band information table downloads

Usage Instructions

Using the Interface

Satellite Resampled Spectra Tab

  1. Select Satellite Sensor: Choose from ASTER, Landsat8, Sentinel2, or WorldView3
  2. Choose material chapter and family: Select one or more material families from the dropdown (if you are using PC, press Ctrl to select multiple)
  3. Refine Selection: Optionally select specific individual samples
  4. Adjust Display Options: Toggle band centers, ranges, and response functions
  5. View Results: Explore the spectral plots and band information

Full Spectrum Data Tab

  1. Choose Spectrometer (optional): Select from available spectrometers (BECK, ASD variants, etc.)
  2. Select Material Chapter and Families: Choose multiple families for comparison (if you are using PC, press Ctrl to select multiple)
  3. Set Wavelength Range: Use the slider to focus on specific wavelength regions
  4. Analyse Data: View high-resolution spectral data and export results

Key Controls

Control Description
material Families Multi-select dropdown for choosing material types
Individual Samples Refined selection of specific samples
Max Samples per Family Limit the number of samples displayed per family
Wavelength Range Filter full spectrum data by wavelength (μm)
Band Options Toggle display of band centers, ranges, and response functions

Application Structure

├── app.py                          # Main application file
├── requirements.txt                # Python dependencies
├── components/                     # UI components
│   ├── satellite_tab.py           # Satellite data interface
│   ├── full_spectrum_tab.py       # Full spectrum interface
│   ├── header.py                  # Application header
│   └── ui_tags_setup.py          # CSS styling
├── USGSSatelliteSpectra.py     # Satellite data handler
├── USGSSpectralLibrary.py                 # Full spectrum data handler
├── USGSUtils.py                   # Utility functions
├── USGSVisualisation.py           # Static visualisation functions using matplotlib
├── USGSPlotly.py           # Interactive visualisation functions using plotly
└── pickle_data/                   # Cached data files for better performance
   

Supported Satellites:

  • ASTER: Advanced Spaceborne Thermal Emission and Reflection Radiometer
  • Landsat8: Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS)
  • Sentinel2: MultiSpectral Instrument (MSI)
  • WorldView3: High-resolution multispectral satellite

Supported Spectrometers:

  • BECK: Beckman 5270 (0.2-3.0 μm)
  • ASDFR: ASD FieldSpec Standard Resolution (0.35-2.5 μm)
  • ASDHR: ASD FieldSpec High Resolution (0.35-2.5 μm)
  • ASDNG: ASD FieldSpec Next Generation (0.35-2.5 μm)
  • NIC4: Nicolet FTIR (1.12-216 μm)
  • AVIRIS: NASA AVIRIS Imaging Spectrometer (0.37-2.5 μm)

Data Caching

The application automatically caches processed data in the pickle_data/ directory:

  • S07{satellite}{chapter}.pkl: Cached satellite data for chosen chapter
  • splib07b{chapter}_data.pkl: Cached full spectrum data for chosen chapter

This improves loading times for subsequent uses.

Performance Tips

  1. Memory Management: Start with smaller sample sizes when exploring large datasets
  2. Wavelength Filtering: Use wavelength range filtering to focus analysis and improve performance

This tool is valuable for:

  • Remote Sensing: Satellite sensor analysis and band selection
  • material Identification: Spectral signature comparison and analysis
  • Geological Research: material composition studies
  • Sensor Calibration: Understanding instrument response characteristics
  • Education: Teaching spectroscopy and remote sensing concepts

Data Sources

This application uses the USGS Spectral Library Version 7 (splib07):

  • Kokaly, R., Clark, R.N., Swayze, G.A., Livo, K.E., Hoefen, T.M., Pearson, N.C., Wise, R.A., Benzel, W.M., Lowers, H.A., Driscoll, R.L., and Klein, A.J., 2017, USGS Spectral Library Version 7 Data: U.S. Geological Survey data release, https://dx.doi.org/10.5066/F7RR1WDJ.

The atmospheric transmission data used in the application is sources from MODTRAN:

  • Berk, A., P. Conforti, R. Kennett, T. Perkins, F. Hawes, and J. van den Bosch. 2014. “MODTRAN® 6: A major upgrade of the MODTRAN® radiative transfer code.” 2014 6th Workshop on Hyperspectral Image and Signal Processing: Evolution in Remote Sensing (WHISPERS), 24-27 June 2014.

  • Berk, Alexander, Anderson, Gail, Bernstein, Lawrence, Acharya, Prabhat, Dothe, H., Matthew, Michael, Adler-Golden, Steven, Chetwynd, James, Richtsmeier, Steven, Pukall, Brian, Allred, Clark, Jeong, Laila, and Hoke, Michael. 1999. “MODTRAN4 radiative transfer modeling for atmospheric correction.” Proc.SPIE.P. Anderson Gail, S. Bernstein Lawrence, K. Acharya Prabhat, H. Dothe, W. Matthew Michael, M. Adler-Golden Steven, H. Chetwynd James, Jr., C. Richtsmeier Steven, Pukall Brian, L. Allred Clark, S. Jeong Laila, and L. Hoke Michael. 1999. “MODTRAN4 radiative transfer modeling for atmospheric correction.” Proc. SPIE.

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An interactive web application for exploring and visualising mineral spectral data from the USGS Spectral Library.

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