A GENERAL PURPOSE ROCK AND MINERAL HYPERSPECTRAL REFLECTANCE LIBRARY FOR EARTH SCIENCE EDUCATION AND RESEARCH (350 TO 2500 NANOMETERS)

Excellent mineral spectral libraries for hyperspectral remote sensing education and research are available from the USGS and NASA. Few spectral libraries specifically for rocks of known provenance are, however, available. Central State University has constructed a general-purpose rock spectral library for Earth Science education and research accordingly. We measured 59 well known samples from the Ward's Natural Science collection of textbook rock and mineral specimens for the sake of demonstration, standardization, documentation and convenience. We used Analytical Spectral Devices Field Spec Pro full range (350-2500 nm) spectroradiometer number 6321/2. Samples were illuminated with an artificial incandescent light source in an airconditioned (low humidity) laboratory. We used a VNIR integration time of 34 milliseconds. There were 10 samples per recorded spectrum. Each spectrum was digitized to 16 bit spectral values. The join between VNIR and SWIR spectrometer 1 was 967 nm. The join between SWIR spectrometer 1 and SWIR spectrometer 2 was 1770 nm. The VNIR values were dark signal subtracted with 25 dark measurements taken per sample. The DCC value was 0. All data were compared to a NIST traceable white reference. Ten white reference measurements were taken per recorded spectrum. Fifty spectra were averaged for each rock or mineral specimen to create a characteristic spectrum with high signal-to-noise ratios and to reduce BDRF effects for each rock or mineral specimen. There was no fore-optic attached to the spectrometer. All spectrum files were recorded as reflectance data. This spectral reflectance library is to be used as a first pass for geologic mapping using atmospherically corrected (reflectance) hyperspectral imagery from aircraft and spacecraft. The spectral library will be available from the USGS EO-1 web site as part of the user guide (http://eo1.usgs.gov).