Evaluation of rock faces with hyperspectral imaging

Hyperspectral imaging is a technology that uses non-visible portions of the electromagnetic spectrum to identify and categorize different objects. While this technology has been used for decades with satellite imagery it is only recently that ground based applications have been explored for purposes such as mineral identification. [1] Each mineral has areas on the spectrum where they absorb the most energy, and by filtering the light before it strikes a sensor it is possible to determine what mineral is being observed. Clay minerals have several absorption peaks in the short range infrared spectrum which can be used for identification. [2] When creating geologic models, the presence of clay minerals can greatly affect the stability of the slope due to reduced friction angle and strength properties. A compact infrared hyperspectral SWIR/MWIR imaging polarimeter (IHIP) was employed in recording the infrared spectrum from 1.4um to 6um and was used to capture several images from a test site on Mount Lemmon, AZ. Mathworks MATLAB was used to view and process the data, including the use of a linear un-mixing algorithm to computer relative abundances of end member spectral data [3].