Southern Mapping Company, an independently owned light detection and ranging (Lidar) and aerial surveying company has invested in hyperspectral imaging equipment that is set to revolutionize the mapping industry in South Africa.

Peter Moir, Southern Mapping Company chief executive says, “The current Lidar equipment at Southern Mapping is able to produce a three-dimensional digital terrain model on which the images are placed. With the addition of the hyperspectral remote sensing technology, we will now be able to identify areas suitable for forestry, agricultural development or mining areas suitable for exploration.”

Hyperspectral remote sensing and imaging, a result of the integration of optical remote sensing and traditional spectroscopic technologies, is able to differentiate the unique spectral signature of minerals that comprise the surface of the earth. Hyperspectral imaging collects and processes information from across the electromagnetic spectrum.

Unlike the human eye, which just sees visible light (blue, green and red), hyperspectral imaging is able to detect visible light, ultraviolet and infrared. Certain objects leave unique fingerprints across the electromagnetic spectrum. These fingerprints are known as spectral signatures and enable the identification of the materials that make up a scanned object.

“The hyperspectral sensors collect the individual reflectance spectra for each pixel element across an image, thus being able to map individual minerals of importance for mineral exploration. For example, if a mining company has the spectral signature for a recently surveyed area, they will be able to identify the region/band that is richest in copper content. This saves on time and reduces the cost of exploration and labour,” says Moir.

The hyperspectral sensors collect information as a set of images. Each image represents a range of the electromagnetic spectrum and is also known as a spectral band. These images are then combined and form a three dimensional hyperspectral cube for processing and analysis. All minerals reflect and absorb energy in both the visible and non-visible portions of the electro-magnetic spectrum.

Says Moir, “This hyperspectral technology coupled with our laser systems (Lidar) and our standard airborne cameras provides our clients with the comprehensive mapping solutions they require.”

The hyperspectral maps indicate a surface mineral abundance thus being the equivalent of a geochemical map, therefore when technology of this nature is used, hyperspectral is often referred to as ‘airborne geochemistry’.

Agricultural departments may also reap the benefits of this type of technology. For specific crops and in specific climates hyperspectral remote sensing is used for monitoring the development and health of crops. With so many Africans on the verge of starvation, research could pave the way in finding pockets of opportunity for agricultural development. According to Moir, the trend for the future is for the industry to find solutions for applications that would enhance the socio-economic development of the continent thus providing a strategic contribution towards growth and sustainability. “As poverty alleviation, water supplies, and floodplain mapping are intrinsic for the well-being of the people of Africa, our services and technology will be deployed to find solutions for all the relevant authorities.” says Moir.

The hyperspectral method has several advantages. It provides geological and mineral mapping capability at regional and project scale, it improves the target selection process and lowers the cost of exploration.

Southern Mapping Company is working in conjunction with the Council for Scientific and Industrial Research (CSIR) to promote the research and development of the use of hyperspectral technology in South Africa.

For further information regarding airborne hyperspectral technology contact Steven Jonker at setven@southernmapping.com.