research
District-level mineral survey using airborne hyperspectral data, Los Menucos, Argentina
- Publication date
- Publisher
Abstract
The Los Menucos District, Rio Negro, Argentina, provides an excellent case history of a complex epithermal
gold system mapped and explored using a combination of field mapping and multispectral/hyperspectral remote
sensing. The district offers a host of argillic and advanced argillic alteration minerals at the surface, many of
which are difficult to identify visually. A strategy utilizing regional targeting with Landsat TM to optimize field
mapping followed by district-level survey with hyperspectral imaging (HSI) data demonstrates the value added
by high-spectral resolution aircraft data. Standardized analysis methods consisting of spatial and spectral data
reduction to a few key endmember spectra provides a consistent way to map spectrally active minerals. Minerals
identified in the Los Menucos district using the JPL Airborne Visible/Infrared Imaging Spectrometer
(AVIRIS) include hematite, goethite, kaolinite, dickite, alunite, pyrophyllite, muscovite/sericite, montmorillonite,
calcite, and zeolites. Hyperspectral maps show good correspondence with the results of field reconnaissance
verification and spectral measurements acquired using an ASD field spectrometer. Further analysis of Hyperion
(satellite-based) hyperspectral data indicates that similar mapping results can be achieved from satellite
altitudes. These examples illustrate the high potential of hyperspectral remote sensing for geologic mapping and
mineral exploration