Although Alaska contains vast mineral deposits, its size and remoteness have prohibited study and extraction of these resources. To remedy this, the U.S. Geological Survey (USGS) began the Alaska Hyperspectral Project to assess the applicability of hyperspectral surveying to rapidly acquire data about the distributions of surficial materials, including different types of bedrock and ground cover.
Hyperspectral data have been collected at the following scales: 1) regional, 2) outcrop and 3) hand specimen. The regional airborne survey, conducted over two days, used the HyMap sensor and provides spectral characterization of surface materials across an extensive area (1,900 square kilometers) at six-meter resolution.
A ground-based outcrop-scale survey done with the HySpex sensor provides higher spatial resolution mineral mapping over a kilometer-scale hillside at 30-centimeter resolution. The most-detailed data were collected at 500-micrometer spatial scale on individual rock samples in the laboratory using Corescan’s Hyperspectral Core Imager Mark III imaging spectrometer.
An outcrop mineral-classification map was generated from 30-centimeter-resolution data collected using a HySpex spectrometer. The different colors indicate a predominance of clays, muscovite and gypsum across the hillside.