Geological Mapping using Mineral Absorption Feature-Guided Band-Ratios Applied to Prisma Satellite Hyperspectral Level 2D Imagery
Carsten Laukamp
Abstract
Spaceborne Earth observation information (EOI) provides cost-effective, spatially comprehensive information for mineral exploration. The spatially contiguous EOI baseline data support geological mapping in addition to information about vegetation, water, and soils and are crucial for a more sustainable development of natural resources. This paper shows examples of PRISMA-derived mineral maps for mapping bedrock geology and regolith. Mineral absorption feature-guided band ratios were applied to PRISMA hyperspectral visible-near infrared (VNIR) and shortwave infrared (SWIR) imagery and compared with previously published airborne hyperspectral imagery for geological mapping. Felsic bedrock is successfully mapped using an Al-sheetsilicate abundance index and discriminated from mafic bedrocks identified by chlorite-epidote abundance and SWIR-active mafic minerals abundance indices. Regolith types are mapped by using the Fe (oxyhydr-) oxides abundance and the kaolin crystallinity index.