Geophysical inversion of imaging spectrometer data for geologic modelling
Imaging spectrometers acquire physical measurements of radiation in many small and contiguous wavebands in order to produce continuous spectral information that can be compared directly with measurements made in the field or laboratory if the atmospheric attenuation is compensated for. Widely used processing strategies compare unknown pixel reflectance spectra with known field or laboratory spectra and derive statistical measures of the goodness-of-fit of these measurements. In geological remote sensing practice these yield 'mineral maps' that on a pixel-by-pixel basis portray the similarity of the measured signal with that of signatures of known minerals. With this information, geologists can build up a geological model of an area. Here the reverse processing strategy is proposed, introducing the geologic model (where geology is converted to physical measurements by introducing spectra) at the start of the processing chain and refining the model in an iterative way by comparing its mismatch with observed reflectance measurements.