http://www.engineeringnews.co.za/article/laser-mapping-for-mining-exploration-infrastructure-development-2011-02-25

Laser mapping eases infrastructure development

Published 25 Feb 11
Aerial mapping company Southern Mapping Company and its South African subsidiary, Southern Mapping Geospatial, use near-infrared lasers in aircraft to map large areas in high detail specifically for the agriculture, mining and infrastructure development sectors, as well as for disaster management purposes, says Southern Mapping Company CEO Peter Moir.

The company, which works mainly in sub-Saharan Africa, does most of its work for mining and mineral exploration companies. Engineers use the data from the survey to plan pit expansions, design new infrastructure such as roads, determine where to sink the next shaft and calculate earth-moving cut-and-fill operations, he notes.

“We do a lot of work for opencast mine operators, which use our data to calculate the volumes of earth that were moved. “The interest is such that one mining company has approached us to do surveys of the stockpiles every week,” says Moir.

Geologists conducting airborne electromagnetic surveys of a concession area use the data from Southern Mapping Company’s surveys to identify possible concentrations of ore deposits, leading to reduced exploration drilling and increased accuracy of exploration.

“Using our technology, geophysical surveys (exploration drilling), and a technique called hyperspectral analysis, the client can identify likely areas of enrichment with high accuracy,” he says.

Meanwhile, t

he main interest from countries in Africa is around infrastructure and agricultural development. “Roads, rivers, railways, power lines and urban sprawl surveys are all in our repertoire,” he says.

The company has measured the urban sprawl of the informal settlement on the outskirts of Polokwane, in Limpopo, and has tracked through time the reduction of the size of the informal settlement and the proportional increase of the size of the formal housing area springing up next to the settlement, he says.

Meanwhile, the company is mapping a 500-km-long railway line route in the Republic of Congo (Brazzaville). Similarly, it has mapped power lines in Kenya and is busy surveying power lines in Mozambique.

Further, by measuring the power lines and taking into account the weather conditions at the time of the survey, as well as the composition of the power cables, the company can determine which power lines can carry more electricity.

To this end, the company also commissioned tests to determine the amount by which the power can be increased and found that one major power line route in South Africa can carry 64% more electricity than it is used for and another power line can carry 51% more electricity than it currently does, he notes.

Moir identifies two main long-term trends for the company, including red, green and blue laser systems that will enable aircraft to measure the colours of points mapped without the need for photographs, even at night. A second trend is to place the systems into unmanned aerial vehicles that will conduct flights without the need for human pilots, he concludes

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