EXPERT SYSTEM-BASED MINERAL MAPPING IN NORTHERN DEATH-VALLEY, CALIFORNIA NEVADA, USING THE AIRBORNE VISIBLE INFRARED IMAGING SPECTROMETER (AVIRIS)

Integrated analysis of imaging spectrometer data and field spectral me asurements were used in conjunction with conventional geologic field m apping to characterize bedrock and surficial geology at the northern e nd of Death Valley, California and Nevada. A knowledge-based expert sy stem was used to automatically produce image maps showing the principa l surface mineralogy from Airborne Visible/Infrared Imaging Spectromet er (AVIRIS) data. Linear spectral unmixing of the AVIRIS data allowed further determination of relative mineral abundances and identificatio n of mineral assemblages and mixtures. The imaging spectrometer data s how the spatial distribution of spectrally distinct minerals occurring both as primary rock-forming minerals and as alteration and weatherin g products. Field spectral measurements were used to verify the minera l maps and field mapping was used to extend the remote sensing results . Geographically referenced image maps produced from these data form n ew base maps from which to develop improved understanding of the proce sses of deposition and erosion affecting the present land surface.