It is probably the oldest form of remote sensing, dating back to 1858 when the first aerial photographs were taken from a balloon. By the turn of the century, precise measurement methods, as we know today, were developed in South Africa (Prof Fourcade, 1901) and in Germany (Dr Pulfrich, 1902). By 1904, the first topographical maps were being produced and in 1910, the International Society of Photogrammetry was founded in Austria.

Since then, the science of photogrammetry has remained at the forefront of technology, driven by the military and cultural applications defined by modern society. Recent major developments in digital photogrammetric software have included missile topographical and target recognition requirements.

Applications extend from ultra-precise close-range photogrammetry used in aircraft construction and biomedicine, to aerial photogrammetry, to satellite image photogrammetry. The associated resolution of measurements extends from sub-millimetres to tens of metres. Computer processing power and image correlation techniques are currently revolutionising the photogrammetric mapping industry.

AATS Surveying and Mapping has established itself as one of the leading photogrammetric practices in South Africa and is moving strongly into the international arena. Its capabilities include close-range terrestrial, standard terrestrial and aerial photogrammetry. Recent visits from large international surveying and mapping organisations have resulted in a strategic alliance being formed with one organisation and a proposal to use the mapping services of the Business Unit being received from the other. The business opportunities presented include mapping of portions of the United Kingdom, and Trinidad and Tobago. Mike Livingstone-Blevins is the Manager of the AATS Surveying and Mapping Unit. He heads up a 12-person team that includes surveyors, photogrammetrists and CAD draughtspeople. Technical resources of AATS Surveying and Mapping include state-of-the-art digital mapping workstations (Intergraph IMD and IMZ II), an analytical workstation (Intergraph IMA), precise scanning equipment (Zeiss/Intergraph PS1) and metric terrestrial cameras. AATS acquired its Intergraph workstations from Intergraph Systems, a subdivision of JSE-listed Fintech. Additionally, AATS has an advanced capability to perform digital aerial triangulation, ie the technique of creating artificial photo control points, using highly complex image correlation and mathematical block adjustment software. As a business unit which has developed to satisfy the surveying requirements primarily of Anglo American group operations, the unique selling point of the unit is: "We know the mining and minerals industry better than any other local competitor, and we understand our clients survey objectives." AATS Surveying and Mapping sees its market niche within this industry, providing its clients with accurate spatial information with which to influence project decisions. It is this high quality that adds value, as recently demonstrated on several projects. Underpinning the ability to provide accurate mapping is 'quality at source' - ie high quality ground surveys which link the photography to the ground, to enable mapping in the relevant survey system. In terms of the use of photogrammetry and the general mining process, Livingstone-Blevins says there is project involvement from the very beginning. "Photogrammetry is used mainly in the pre-feasibility and feasibility stages with exploration as the main thrust. It's highly important to have accurate spatial information at the inception of the project. This means that there is no need to rehash the information later if it is done accurately up front, and it allows one to make decisions based on quality information. AATS Surveying and Mapping is working on a mix of projects at the pre-feasibility, feasibility and exploration stages, in countries as far flung as Morocco and Colombia." Livingstone-Blevins adds that AATS also has the added responsibility of involvement in the regular work of operating divisions; in other words, overseeing the quality of survey practise on established mines and keeping it updated. He says the focus with these established mines is in SADC countries, and makes the interesting point that AATS operations frequently take place in countries in which there is no real access to reliable or recently updated maps. "A fair amount of regional mapping takes place," he says, "to allow geologists to review topographical features as well as to identify possible target areas. There is great synergy between surveying and mapping and the Geophysical Services Department, which also provide large amounts of geospatial information." Projects for which the Business Unit is providing photo ground control and mapping services include Seksaoua Project (Morocco), Carbones del Cerrej¢n (Colombia), Gamsberg Zinc Project (South Africa), Kabanga Nickel Project (Tanzania) and the Skorpion Zinc project (Namibia).

Intergraph Systems Southern Africa

(011) 313 1222

pjvaarsveld@intch.co.za