Mineral mapping of the Palai area with hyperspectral remote sensing
This is an easy exercise that shows how airborne hyperspectral remote sensing imagery can be used to map surface minerals. You will construct a map that shows the depth and the wavelength position of the deepest absorption feature between 2100 and 2400 nm. The analysis of the map will help to define areas that are illite-rich. The illite minerals in the Palai area are of hydrothermal origin, and they indicate alteration zones that are related to gold and base-metal mineralization. Optionally, the mineral gypsum is mapped using the wavelength range between 1650 and 1820 nm.
The exercise was developed in 2012 for the advanced remote sensing course of block 2 in the AES MSc program at the faculty of ITC of the University of Twente. I have also used the exercise for the workshop on Hyperspectral Remote Sensing at the Conference of African Geology in 2013 in Addis Abeba, and since 2015 in a guest lecture for the Earth Resources course at Utrecht University. A document with example answers to questions in the instructions, and an example map is available.
The area can be found in Google Earth at approximately 37.0140 lat; -1.9335 lon.
• Instructions: Ex - Mineral mapping of the Palai area.pdf
• Hyperspectral image: Hymap_Carboneras_refl; Geological map: Carboneras_geology_sub; Reflectance spectra: field spectra - folder
• Example answers to questions: Ex - Mineral mapping of the Palai area – ANSWERS.pdf
Hyperspectral mapping of alteration minerals in the footwall of the Kangaroo Caves VMS-deposit
This exercise is about mapping subtle spectral differences between minerals in an Archean hydrothermal alteration system. It shows how the wavelength position of white mica minerals can be used to trace alteration zonation that is related to hydrothermal discharge sites and massive sulfide deposition. Field spectra will be used together with airborne hyperspectral imagery and a variety of methods to make mineral maps. The exercise uses ENVI software, most of the steps, however, can also be performed using HypPy software.
The exercise was developed and used in 2009/2010 for the advanced remote sensing course of block 2 in the AES MSc program at the faculty of ITC of the University of Twente. I have also used the exercise for a refresher course in 2010 at SEAMIC (now known as African Minerals and Geosciences Centre) in Dar es Salaam, Tanzania, for ITC alumni from Eastern and Southern Africa. A document with example answers to questions in the instructions and a overview of results are included in the download.
The area can be found on Google Earth at approximately -21.2085 lat; 119.2371 lon.
• Instructions: Ex Kangaroo Caves - instructions.pdf
• Hyperspectral image: pn12reflectance; Reflectance spectra: spectra – folder; Sample locations: KangarooCaves_spectra.shp; ROIs: groundtruth.roi
• Example answers to questions: Ex Kangaroo Caves - instructions – ANSWERS.pdf
• Overview of selected results: Selected results.pdf
The Hyperspectral game
The hyperspectral game is NOT a step-by-step tutorial that guides you through the exercise. In the hyperspectral game, you are free to choose your method of interpretation of hyperspectral data. You can choose your preferred technique to analyze a hyperspectral image and produce mineral maps. By conducting the game with a group of people, and comparison of the results, you learn about the need for standardization and become aware of the range of available approaches.
The hyperspectral game was developed in 2012 and was available at the website of the faculty of ITC of the University of Twente for several months. Later the exercise was used for the workshop on Hyperspectral Remote Sensing at the Colloquium of African Geology in Addis Abeba in 2013.
The area can be found on Google Earth at approximately: …?
• Instructions: Hyperspectral game - instructions.pdf
• Hyperspectral image & ASCII spectra
• Example results are not available.